Online Chatroom Archives

2006 National DNA Day Online Chatroom Transcript

The 2006 National DNA Day Moderated Chat was held on Tuesday, April 25th, 2006 from 8 a.m. to 6 p.m. Eastern. NHGRI Director Francis Collins and genomics experts from across the institute took questions from students, teachers and the general public on topics ranging from basic genomic research, to the genetic basis of disease, to ethical questions about genetic privacy.

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Information - Moderator Good morning! Welcome to DNA Day 2006! From 8 a.m. to 6 p.m. Eastern, experts from the National Human Genome Research Institute will be answering your questions in this chatroom. We will try to answer as many questions as possible, so start sending them in!

Information - Moderator Joining us in our first hour are NHGRI's Scientific Director Eric Green; Vence Bonham, chief of our Education and Community Branch; Belen Hurle, a Research Fellow and Science Educator, and Dale Lea, a Health Educator.

What kind of new and exciting applications do you hope for in the field of medical genetics in the near future?
     Dale Lea, R.N., M.P.H., C.G.C: The most promising application in medical genetics is the area of individualized prevention and treatment. Pharmacogenetics is an emerging application where individuals have gene testing or testing of metabolizing enzymes to determine the right medication and the right dose of a medication. This approach to treatment means more effective treatment and reduced risk for side effects and adverse reactions.
St. Ignatius College Prep High School
If you had billions of dollars for your research what (in your research) will you spend it on?
     Eric Green, M.D., Ph.D.: Not a totally hypothetical question! Our Institute (the National Human Genome Research Institute) receives almost a half of a billion dollars each year to perform and/or fund genetics and genomics research. This government funding comes with a great responsibility-- to ensure that we use that money in the most effective way possible. You can learn quite a bit about what the National Human Genome Research Institute does with its half-billion dollars per year by visiting our web site at This includes a diverse set of programs, ranging from understanding how the human genome functions to developing new ways to treat genetic disease to studying the societal implications of that work. But there are always additional important things we can envision doing if additional funds would become available.
Koshland DNA Day participant
Can genetics tell us exactly how infants will react in life?
     Dale Lea, R.N., M.P.H., C.G.C: Genetics, at this point in time, cannot tell us exactly how infants will react in life. There is genetic testing for specific genetic disorders, such as cystic fibrosis or Down syndrome. Ultimately how an infant will grow and develop is a combination of nature and nurture.
Koshland DNA Day participant
Although we are flooded with references that claim racial differences cannot be traced to genes, it is clear that the FBI and associated police investigative agencies regularly use racial profiling for orienting their DNA testing data to specific criteria and for their statistical interpretations. How do we reconcile these two phenomena? There was news last fall that reported findings on a certain cluster of genes related to controlling some aspect of skin pigmentation. Will we hear more about the applications of this research in the future?
     Vence Bonham, J.D.: Race is a social construct that has changed over time. If you review how we have collected race in the history of the United States and other countries in the world it is clear that race is a social and political construct. Researchers and law enforcement agencies can use specfic biomarkers, including ancestral identification markers to make statistical estimates of an individual's ancestral background. This background may correlate with our social constructs of race. Researcher Keith Cheng and colleagues identified a gene called SLC24A5 which affects pigmentation (skin color) of humans. It would be a terrible mistake to conclude that a gene involved involved in skin color is really a gene for "race".
St. Ignatius College Prep High School

Information - Moderator Also here today is Sarah Harding of Education and Community Involvement Branch.

How much of the genome do we have specific function information for?
     Eric Green, M.D., Ph.D.: A great question-- and something that represents one of the highest priority areas of genomic research right now. The short answer is 'very little at the present time'!!! We probably have reliable functional information for 1-2% of the human genome at present; meanwhile, we think that only about 5% of the human genome is functionally important. That leads to the obvious (and challenging) question of 'what does the other ~95% of the human genome do?" We plan to leave that hard question to YOUR generation of scientists...
Zac Trupp-Wootton High School
Two related questions came in at about the same time: "Can we eat DNA?" And "What does DNA task like?"
     Eric Green, M.D., Ph.D.: We eat DNA all the time-- it is in all meat, all fruits, all vegetables, and so forth. Anything living has DNA in it. In terms of DNA tastes like-- must be chicken (doesn't everything taste like chicken?).
Should American doctors be under pressure to "encourage" all mothers-to-be to do prenatal screening as part of normal prenatal care?
     Dale Lea, R.N., M.P.H., C.G.C: American doctors are obligated by the American College of Obstetrics and Gynecology to offer all mothers-to-be prenatal screening for conditions such as spina bifida and Down syndrome. It is the pregnant woman's option to choose to have or not to have prenatal screening.
St. Ignatius College Prep High School
Are you currently accepting internships?
     Sarah Harding, M.P.H.: The National Institutes of Health has summer internship opportunities available, but it's necessary to apply early. The internships are available at many of the Institutes at NIH, including the Genome Institute. The applications for the 2006 summer has closed, but will open for 2007 in mid-November. You can find more information at
It seems that the availiability for new discoveries in the field of genetics is slowly decreasing. Now that the human genome has been sequenced what is left?
     Eric Green, M.D., Ph.D.: Don't let the excitement of completing the Human Genome Project lead you to think that genetic discoveries are slowing down. Indeed, it is just the opposite. The Human Genome Project provided an unprecedented set of tools and resources that is actually accelerating all aspects of genetics research. And indeed, there is a remarkable set of discoveries that remain to be made-- some of the most compelling ones relating to the identification of genes associated with common diseases (heart disease, cancer, autoimmune disease) and better understanding how something as simple as DNA can encode all life processes.
Ben Plotsky, Thomas S. Wootton High School
What career route would I take to be able to interact and talk with pregnant women and infants, and still work on the genetics of the infants? In this career would you be able to "monitor" the infants/pregnant women?
     Dale Lea, R.N., M.P.H., C.G.C: There are several career paths you could consider. One is becoming a genetic counselor, where you would provide counseling to pregnant women considering genetic testing and working with a medical geneticist in evaluating infants for potential genetic conditions. Genetic counselors follow pregnant women and infants over time to monitor a pregnancy or an infant's growth and development.
Janell Holloway: Banneker AHS
DNA Day Finally here!!! DNA Day CHEER, CHEER, CHEER!!! DNA Day Really Rocks!!! GOOOO Double Helix!!!
     Sarah Harding, M.P.H.: Thanks Jennifer! We're excited to be here too!
Jennifer, Maryland
To respond to Zac Trupp's question, there is some belief that the junk DNA may play a role in RNAi when transcribed. How valid of a prospect is this?
     Eric Green, M.D., Ph.D.: Please help me by never using (or allowing your friends to use) the phrase 'junk DNA'-- that phrase really just reflects our lack of knowledge about DNA. Once upon a time, people referred to any DNA that didn't encode protein as 'junk'. We now know that DNA can confer function in many ways other than encoding protein. You mention RNAi, the ability of some DNA sequences to encode the ability to inhibit RNA function. We are just beginning to understand RNAi, but it has taught us that 'junk DNA' sometimes isn't so 'junky' after all.
Tessa Carducci Wootton High School
What is the rarest type of disease that has a genetic basis?
     Dale Lea, R.N., M.P.H., C.G.C: Progeria is one of the rarest genetic conditions in the world. The disease is a uniformly fatal condition affecting 1 in 4-8 million children. There are approximately 35 known cases worldwide of children suffering from Progeria. For mor information about Progeria you can go to or and search for Progeria.
Kris Ferguson, Greenville, Alabama
Are there any restrictions for carrying out gene tests on 20 year olds, to find out whether they are likely to develop genetic diseases such as Alzheimer's disease in their 60s?
     Vence Bonham, J.D.: No. There are no restrictions on testing for genetic risk for Alzheimer's disease and other diseases with a genetic component. However, it raises important clinical and social questions for the individuals if they want to know that information. The United States does not have a federal genetic non-discrimination law that would protect individuals from employment and health insurance discrimination today. SInce there are no restrictions it is important that health professionals and patients be thoughtful before learning information for adult onset disease where there is no treatment. For those reading this what do you think of testing for genetic diseases where there is no therapy?
Shivani, Uni of Leicester, UK
Is the "Gene microchip" mentioned in "Genomics: Towards a Healthier You" something that companies are trying to make available at the very moment? If so, are many people opposed to the idea due to privacy and other rights?
     Eric Green, M.D., Ph.D.: The 'gene microchip' you mention is a recent diagnostic test that is being offered to help guide physicians in prescribing some medications. This reflects one of the earliest implementations of 'pharmacogenetics'-- where drug treatments will, in part, be guided by genetic information about the patient. Because this is so new to physicians and the health care system in the U.S., the usage of this chip is quite low (so far). Concerns about privacy are not really hampering this chip's use; but such concerns are certainly relevant for the broader application of DNA tests.
Lina Feng - Wootton High School
Are gene tests available for complex diseases, diseases which have no cure, or diseases that may have a late onset?
     Dale Lea, R.N., M.P.H., C.G.C: Genetic testing is currently available for genetic diseases such as cystic fibrosis and sickle cell anemia for which there is currently no cure. Genetic testing is also available for adult-onset conditions such as breast and colon cancer and Huntington Disease. We are only beginning to scratch the surface with genetic testing for complex diseases such as heart disease and diabetes.
Shivani, Uni of Leicester, UK
Could DNA be possibly used in the future to help hire people?
     Vence Bonham, J.D.: Yes. As we learn more information about genetic and environmental risk of disease, employers may use genetic information to determine whether a person would be at a health risk if they perform specfic occupations. For example, in the future it may be possible to use genetic tests to determine whether an employee would react negatively to a certain chemical they need to use in their work. This information could help protect employees from harm.
Josh Lee, TWHS
When considering the full sweep of medical challenges to public health internationally today, where should most medical research be focused for developing treatments, environmental factors or genetics?
     Dale Lea, R.N., M.P.H., C.G.C: Medical research should focus on all three - treatments, environmental factors and genetics. Each of these areas interacts with and is influenced by the others.
St. Ignatius College Prep High School
What has the Human Genome project told us so far, and how does it help is in our daily lives?
     Eric Green, M.D., Ph.D.: Two very different questions. The Human Genome Project has advanced our understanding of how the human genome works and how, when altered, it can lead to disease. To be honest, this has mostly accelerated the work of scientists and clinicians, and probably hasn't changed the lives of a typical person today. But empowered with that information, we are now hard at work to use the fruits of the Human Genome Projects to advance our ability to diagnose, manage, and treat human genetic disease. With time, we expect this will change the lives of people, but this may take some time.
Michael Wu - Wootton High School
Is there any way to determine whether or not I have a genetic disorder without using karyotyping?
     Dale Lea, R.N., M.P.H., C.G.C: Yes, there are several ways. Karyotyping (analyzing a person's chromosomes) is only one type of genetic test. Other genetic tests available to determine whether a person has a genetic disorder include DNA analysis and metabolic/biochemical testing.
Ben Plotsky, North Potomac, MD
What advances or cures do you think studying genetics will yield in the next 5-10 years?
     Eric Green, M.D., Ph.D.: The last 5-10 years have seen remarkable advances in our ability to identify the gene defects associated with rare genetic diseases. We expect the next 5-10 years to bring similar advances in the identification of gene defects associated with the more common genetic diseases-- disorders that are seen more frequently in hospitals and clinics every day (heart disease, asthma, autoimmune disease, mental illness). With this will come opportunities to diagnose genetic diseases well in advance of the development of symptoms, hopefully leading to better management of these illnesses.
Koshland DNA Day participant
In the future, will it be possible to change DNA in place of plastic surgery?
     Dale Lea, R.N., M.P.H., C.G.C: Right now we don't have a way to alter a person's DNA to make them thinner or younger looking in place of plastic surgery. But who knows what possibilities our knowledge of DNA and genomic sequence will bring!
Katie H and Sam S
In the future, will parents be able to change the DNA of an embryo so that the child will have certain characteristics?
     Eric Green, M.D., Ph.D.: What you suggest is really quite complicated and perhaps will never be possible. Even if possible, we should think long and hard about whether this should be done as well as under what circumstances should it be done. There are many important genetic advances that should be possible in the near future and that are far less controversial, and those are the ones we are focusing on at present.
Chris Walka, Marshfield MA

Information - Moderator We've been getting some great questions--keep on sending them! And remember to visit the chatroom at 3 p.m. Eastern to lfind out the winners of the American Society for Human Genetics' essay contest for high school students.

What improvements have been made in the ethical, legal and social implications since the start of the human genome project?
     Vence Bonham, J.D.: When the Human Genome Project was started in 1990 a commitment was made to address the ethical, legal and social implications of our knowledge about the human genome at the same time we sequenced the human genome. Since 1990 the National Institutes of Health under the direction of the National Human Genome Research Institute has spent millions of dollars, more than five percent of its budget annually, to studying the ethical, legal and social implications of sequencing the human genome. Today there are scholars across the world that are developing policies and guiding scientists as they move forward in genomic science. This work has created an important framework through which we can explore the questions and implications of genetics research as it improves at a rapid pace.
Shivani, Uni of Leicester, UK
What are some of the dangers of adult screening? Are most doctors receiving the training necessary to make wise decisions on recommending genetic tests to their patients?
     Dale Lea, R.N., M.P.H., C.G.C: Education to increase awareness of all health professionals (doctors, nurses, physician assistants, genetics professionals), is increasing both in content and quality as new genetic discoveries are made so that their recommendations to patients are reliable and based on current knowledge of genetics and genomics. As far as the dangers of adult genetic screening, the main issues that have been raised include privacy and confidentiality of genetic information and the possibility of discrimination (insurance, employment discrimination).
St. Ignatius College Prep High School

Information - Moderator Carla Easter of the Education and Community Involvement Branch has just joined us to help asnwer your questions.

18. Considering the many new developments in DNA research that are shifting scientific paradigms, do you have any particularly ?out of the box? ideas about DNA, RNA, introns, pseudogenes, alternative splicing or repeat sequences, in general? What are of genetic studies do you find most exciting to discuss with your colleagues when the situation arises?
     Eric Green, M.D., Ph.D.: In my opinion, one of the most exciting aspects of genomics research at the present time is the search for new ways that DNA can confer function. It is my belief that there are great new discoveries to be made-- and in fact, there will turn out to be a large number of ways that DNA can encode function that are not yet described in textbooks today. When I talk with my colleagues, I am most excited about describing how we are using evolutionary clues to decipher functional information in the human genome. This involves sequencing the genomes of diverse sets of animals-- from fish to birds to mammals to primates-- and then finding the same sequences and functions in all of these creatures, even though they have very different evolutionary histories.
St. Ignatius College Prep High School
What is the general opinion of the genetics community regarding genetic testing for women who may carry the breast cancer gene or other similar genes? How does this testing help the individual?
     Dale Lea, R.N., M.P.H., C.G.C: The general opinion of the genetics community is that genetic testing for hereditary breast/ovarian cancer gene mutations should be offered to any woman who has a certain specific family history pattern of breast/ovarian cancer (for example, two or more close relatives with breast/ovarian cancer). Genetic testing for breast/ovarian cancer gene mutations is not currently offered to all women in the general polulation. Genetic testing for hereditary breast/ovarian cancer gene mutations can help a woman at risk know whether she has inherited a particular breast ovarian cancer mutation or not. If she has not, then she can follow breast/ovarian cancer screening guidelines similar to the general public. If she has inherited a specific breast/ovarian cancer gene mutation, she can talk with her doctor about inhanced screening, prevention and treatment options. For more information go to
Jenn, Pasadena, Maryland
My students are learning about replication right now is there anything that is new and exciting about DNA replication
     Eric Green, M.D., Ph.D.: DNA replication is a fascinating topic, and one that I know students are intrigued by. Imagine each cell needing to accurately xerox its entire genetic blueprint each time it divides. With such a precise process, one could imagine that defects in replication might lead to disease. Indeed, this is the case. We continue to learn ways in which this xeroxing process can be broken, and the different diseases that result.
Gerald Holton Licking Heights HS
Does DNA have a color?
     Phyllis Frosst, Ph.D.: In solution, DNA is clear. When precipitated from a solution, DNA forms a white stringy material and when dry, DNA is a white powder.
Richard Lui, Newton, MA
With the current DNA testing, do you think in the near future, we'll be able to cure major diseases and complications in the human body?
     Eric Green, M.D., Ph.D.: It is not just DNA testing that will lead to improvements in treating genetic disease. Also associated with genetic and genomic advances will be a better understanding of how DNA defects cause the disease, yielding clues about new treatments. But these are hard problems that will require years of work by scientists and clinicians. There are already wonderful examples of such successes, but many more remain. Some will happen in the near future, others will take longer. We must realistic about these challenges.
Zac leuci - hodgson high school
Will therapeutic cloning, if and when more widely accepted, eventually create an industry of healthcare available only to the wealthy? Is there anyway to safeguard against corporate monopolization of these therapies?
     Vence Bonham, J.D.: A grand challenge for the future of genomic research is to improve the health of all. Steps have been taken to provide genomic data to be available in the public domain so that all researchers have access to the data to identify new therapies and the data is not limited to biotech and pharmaceutical companies.
St. Ignatius College Prep High School
Can you determine when you will die through DNA?
     Eric Green, M.D., Ph.D.: No-- and this will never be possible. Certainly, we will be able to get clues about disease susceptibility by examining an individual's DNA sequence. BUT besides genetic influences, there are very important environmental factors associated with health and disease, and these cannot be predicted by DNA sequence alone.
Steve Brown, Marshfield Ma
Which DNA double helix do you think would be harder to separate into two strands- DNA composed predominantly of AT base pairs or of GC base pairs? Why?
     Phyllis Frosst, Ph.D.: GC base pairs are stronger, due to their three hydrogen bonds (as compared to an AT pair's two), so a DNA composed of mostly Gs and Cs would be harder to separate into two strands.
Vinay, Thomas Sprigg Wootton High School
I heard that the ends of DNA strands are cut off after a cell divides. How does this work and what are the effects as we get older?
     Carla Easter, Ph.D.: The ends of the chromosomes are known as telomeres. They are often compared to the plastic ends on shoe laces. Each time a cell divides a telomere gets shorter. Once the telomeres are too short, the cells can no longer divide and get old and eventually die. This process is associated with aging and cancer. A lot of research has been done on yeast to study the effects of telomere shortening.
What is the biggest misconception the general public has regarding our genome and genetic studies? Where do most people get the wrong ideas about genes and how could this be corrected?
     Eric Green, M.D., Ph.D.: I don't know if it is the 'biggest' misconception, but a common one is that 'genes are everything.' The situation is much more complicated than that-- with both genetic make up and the environment influencing a person's health and other attributes. These environmental factors include things like diet, smoking, exercise, and lifestyle.
St. Ignatius College Prep High School
How many bases are there in a Human DNA molecule?
     Carla Easter, Ph.D.: It all depends on the DNA molecule you are referring to. Typically, we refer to the individual genes within the genome. For example, the smallest gene might have as few as a couple 100 base pairs, while larger genes can easily have 1000's of base pairs.
Nancy Guy
How will the discoveries of the human genome project affect childbirth? Will gametes be examined for the characteristics that they would create and selected to make a "perfect baby?"
     Dale Lea, R.N., M.P.H., C.G.C: Gametes are being screened and examined for specific genetic conditions such as Down syndrome. There is currently much discussion about the ethical issues of creating or selecting genes to create a "perfect baby." But there will always be the question of what qualities and physical characteristics constitute a "perfect baby."
Amelia E. Wootton HS
What can 10th graders do to get involved in real DNA research?
     Belen Hurle, Ph.D.: There are Summer research opportunities for high school students in many colleges and universities. Normally you have to be 16 or older to take advantage of such programs. They typically run for 8 to 10 weeks and they are great. I encorauge you to check the webpages of your local institutions for more information. You can also read as much as you can on DNA and genetics to have a better sense of what areas that excites you the most.
Larry Small, Marshfield, MA
What is your favorite DNA base?
     Eric Green, M.D., Ph.D.: G (for Green), although I don't really dislike A, T, or C.
Sam T, Wootton HS
What is a typical day like for you as a genetics scientist?
     Belen Hurle, Ph.D.: Hello! I am a bioinformatician , which means that I spend most of my day in front of my computer, trying to make sense out of the genomic sequence of the human and other vertebrates with the help of software tools. I hardly ever use a pipet anymore.
St. Ignatius College Prep High School
For a young person interested in science what would you advise them to pursue in genetics? Is the tauted bioengineering field the most promising? What kinds of classes and programs would you recommend for students finishing high school now?
     Belen Hurle, Ph.D.: I think that if you like computers, Bioinformatics is a very hot area. The best programing language to learn is probably perl, but any programing experience in any language would be very helpful for a person considering bioinformatics and genetics. Also be sure to take courses in biology and chemistry. In any case genetics these days is a multidisciplinary field and we all work in teams, each one with a different expertise so that you don't have to know everything related to the research.
St. Ignatius College Prep High School
What institutions, labs, nations should we keep an eye on for further research in gene therapy?
     Phyllis Frosst, Ph.D.: Lots of terrific research in gene therapy is ongoing in the US and around the world. To find out which institutes and labs have recently published exciting research, you can go to medline ( and search for "gene therapy" or search high profile journals such as "Science" or "Nature" or topic-specific journals such as "Molecular Therapy or visit the website of the American Society of Gene Therapy at .
St. Ignatius College Prep High School
Do people have different DNA?
     Belen Hurle, Ph.D.: Our DNA is our unique and personal identification. Only identical twins have identical DNA. Between any two individuals, the DNA sequence is 99.9% identical; the remaining 0.1% difference accounts for all the variation in appearance, disease susceptibility, and even how we respond to drugs.
Koshland DNA Day participant
Has anybody ever read the entire human genome project? Who?
     Belen Hurle, Ph.D.: Letter by letter, I doubt it. We are talking about 3 billion letters! We can analyze the whole genome at once by using computers. This is much better than people dealing with huge genomic databases. The scientist asks the questions, then use different software tools to make sense out of the genome data. Finally, he or she analyzes the computer output looking for answers.
Vu Luong: Banneker AHS
Have scientists finished sequencing the H5n1 virus?
     Carla Easter, Ph.D.: Sixty-two individual samples of the H5n1 (Avian flu)virus were isolated from infected humans and poultry. In 2003, these samples were genetically sequenced. For more information on this, if you really want to know the nitty-gritty, see the journal Nature ( July 2004).
Koshland DNA Day participant
Where do you feel genetics will go in the next 5-10 years?
     Belen Hurle, Ph.D.: I think that genetics is heading in the direction of pharmacogenomics. Variations in individual genes can cause a patient to metabolize drugs abnormally fast, abnormally slow, or not at all. For example, the same dose that is safe for a patient with one genetic variation might be too high (and therefore toxic) to a patient with a different variation who cannot metabolize the drug. In some cases, a doctor can run a genetic test in patients to gather information on their genetic makeup, and use this information to make individualized treatment decisions. This is possible already for some genes, and we expect to see more and more tests available soon.
Koshland DNA Day participant

Information - Moderator Here with us this hour is Phyllis Frosst, a science policy analyst who has done research related to gene therapy.

If a child is up for adoption, should his or her genetic information be collected?
     Vence Bonham, J.D.: It is my understanding that most agencies collect family history. It is not routine to do genetic testing for a child prior to adoption. It is important to remember that we all have genetic variants that may predispose us to certain common diseases.
Shivani, Uni of Leicester, UK

Information - Moderator Also joining us is Chris Austin, director of the NIH Chemical Genomics Center.

What did it feel like to finish mapping out the human genome?
     Eric Green, M.D., Ph.D.: It was way cool! It truly felt like you were part of something of great historic significance.
Read Carney, Newton, MA
What was the most challenging part of sequencing the Human Genome Project?
     Belen Hurle, Ph.D.: There are still "holes" in the human genome. Telomeric and centromeric sequences are difficult because they are very repetitive and the current sequencing technology is not efficient dealing with long repetitive stretches. Fortunately these regions are gene poor. Another problematic area are segments that are duplicated in the genome. We can read them easily, but the problem here is how to order them right. It is like having two identical puzzle pieces that fit equally well and being unable to decide which one fits where.
Brian Petty: Banneker AHS
It seems that since the tragic death of Jesse Gelsinger and the triggering of leukemia in boys undergoing gene therapy, we have not heard of any progress in research on gene therapy. Are there any improvements in developing safe vectors? Should we expect more promising efforts focused on "blocking" disease genes with RNA interference and related RNA methods?
     Phyllis Frosst, Ph.D.: The media has been quiet in the past few years on the topic of gene therapy, but research has been actively going forward and many many interesting research projects are ongoing. The focus of the field has shifted a bit in recent years towards the basic research underlying the mechinsms of gene therapy. The field decided that the best way to move the field forward towards therapies was to have a deeper understanding of how these vector work at the cell and organismal level. That said, ongoing clinical trials are moving forward with exciting and innovative therapies for cancer, diseases of vision, and many other areas. RNA technologies, particularly the use of microRNA, are being actively explored.
St. Ignatius College Prep High School
Right now there are breakthroughs in organ transplants like the recent face transplants. Is it possible to create DNA transplants for those people with genetic diseases?
     Chris Austin, M.D.: Theoretically, yes, and this is known as "gene therapy". The idea is simple: deliver the correct gene (DNA) sequence to people who have a gene that is mutated. This has been going on for nearly 20 years, and is turning out to be much more difficult than anticipated. The reasons for this are, among other things, trouble getting the DNA sequences to enough cells in the right tissues (think of how difficult it is to get the right gene to all 10,000,000,000,000 cells in the brain!), and rejection from the immune system, that tends to see the correct gene (or protein for which it codes), or the "vector" that delivers the gene to the tissues, as foreign, and rejects it. The successes have been in blood disorders (cells are easy to reach) for disorders where only a few cells corrected is enough to help the person. An example of this is Severe Combined Immunodeficiency Syndrome, or SCID.
Haena Cho, Wootton High School
Can the atoms in the DNA molecule actually be seen?
     Eric Green, M.D., Ph.D.: Not directly, at least not with currently available tools. But there are ways to indirectly detect the molecular components of DNA. Indeed, this was originally done by Watson and Crick in the 1950's, leading to the discovery of the double-helical structure of DNA.
Megan Foley, Hazel Park High School
Does DNA affect your intelligence?
     Vence Bonham, J.D.: Yes. Genes and Environment affect your intelligence. This is not a new conversation or debate. It is important to understand that genes alone do not determine your intelligence.
J Watklevicz New York

Information - Moderator Fantastic questions! Just a reminder to please identify your school and where it's located. Thanks!

Are there any predictions as to the function of the 95% unknown genome?
     Phyllis Frosst, Ph.D.: There are lots of predictions, but importantly, lots of research efforts to understand the 95% of the genome that we don't yet understand. A project called ENCODE, which seeks to understand all the functional elements of the human genome, is well underway. For more information, check out
Katie Wilson, T.S. Wootton H.S.
Why does Adenine pair with Thymine?
     Carla Easter, Ph.D.: This is a little technical but not hard to understand. I think the question has to do with the pairing of DNA bases. Adenine and Thymine are always paired and Guanine and Cytosine are always paired. So, "A" pairs with "T", and "C" pairs with "G." So the question asks why does A pair with T. This is due to the chemical structure of each base. Adenine and Thymine establish two hydrogen bonds between them. Guanine and Cytosine establish three hydrogen bonds between them.
Richard, from K-12
What are the latest breakthroughs in RNAi technology and what are researchers currently investigating in relation to this topic?
     Eric Green, M.D., Ph.D.: RNAi is a recently discovered mechanism by which genes can be 'turned off' in a precise way. Some recent breakthroughs have pointed to ways in which RNAi might be modified for therapeutic purposes. Specifically, there are now major efforts to develop drugs based on RNAi approaches. This new strategy for drug development holds great promise.
Tessa Carducci Wootton High School
What, in your view, is the most controversial area of genetic research today?
     Belen Hurle, Ph.D.: A controversial area is how to protect privacy rights and how to avoid genetic discrimination. Who will have access to our genetic records? Who will make medical, employment, or insurance decisions based on our personal genetic profiles? Who will benefit from these news technologies, and who will not? Think about it.
St. Ignatius College Prep High School
Do you think today's society and scientists regard genetic information as a special case or should it be treated in the same way as other "confidential" information," and why?
     Phyllis Frosst, Ph.D.: There's a lot of discussion in the field about the idea of "genetic exceptionalism". Is genetic information truly different from other individual medical information? In many ways it is, and in many ways it is not. What's particularly interesting is that while we can get the sequence of an individual's DNA (although it's pretty expensive right now) we don't yet understand what the health implications are of all the information...but that's changing every day. What might be just As Cs Gs and Ts today, might be recognized as an increased risk of cancer or heart disease tomorrow. Importantly, there is no comprehensive federal legislation in place that protects Americans against insurance and employment discrimination (although there is a patchwork of state laws that offers some protection). For more information about this see
Shivani, Uni of Leicester, UK
As more and more prenatal tests become available and affordable to all Americans, will we screen everyone for every genetic disease known or will tests be designed for specific groups that are known to be at risk?
     Chris Austin, M.D.: This is a great question, and is a topic of great current debate in the medical community. The answer is potentially yes for both parts of your question, and it is not only for prenatal testing, but for newborn testing too. There has been prenatal testing for major genetic defects, and in newborns for "metabolic" diseases like phenylketonuria, for a long time. But as the causes of more genetic disorders become known, more tests are becoming available for both stages. To decide whether testing should be done, doctors and researchers need to balance the likelihood that an individual will have the defect, the availability of an intervention (treatment) if a genetic disease is found, and the cost of testing. Different states are debating how many tests to mandate in newborns, for example. In some cases, these recommendations are for only those with elevated risk to get tested -- such as those with familiy history of a genetic disease, or having ancestry that would make them more likely to have the genetic disease.
St. Ignatius College Prep High School
Since the public easily accepts information about DNA as being absolutely accurate, should we be concerned about current fingerprinting practices being used for evidence for prosecution, paternity testing etc.?
     Vence Bonham, J.D.: It is extremely important to have an informed public. Consumers will need to be able to distinguish misinformation from accurate, scientifically based information.
St. Ignatius College Prep High School

Information - Moderator Joining us now is Vivian Ota-Wang of NHGRI's Ethical, Legal and Social Implications Program.

How much has genetic research advanced in the last year?
     Eric Green, M.D., Ph.D.: The last year has brought remarkable advances in genetics. We continue to make major strides in correlating genetics alterations with specific disease. Our understanding of how the human genome functions continues to grow; some of this has been aided by increasingly powerful comparisons of the human genome sequence with that of other vertebrates. Finally, we continue to refine our strategies for performing large studies that will allow us to identify the genetic alterations that cause common genetic diseases, such as heart disease and cancer.
Paul from Pennsylvania
Why is DNA important?
     Belen Hurle, Ph.D.: It is the book of life; the molecule that stores all the information about who you are and how do you function. It is also the molecule that carries the genetic information from one generation to the next with extreme reliability.
andre scarbrough

Information - Moderator Joining us this hour are NHGRI Director Francis Collins, who led the Human Genome Project; Barbara Biesecker, a genetics counselor who is featured in this year's DNA Day Webcast, and Heidi Parker, a dog genomics expert who is filling in for Nate Sutter.

What is the general procedure for determining disease-causing genes?
     Phyllis Frosst, Ph.D.: Determining disease-causing genes has been revolutionized by the completion of the Human Genome. For conditions caused by a single gene, researchers use families that have a high occurrence of that condition to hone in on the gene. For diseases that have complex inheritance, caused by multiple genes, such as diabetes or heart disease, researchers use groups of thousands of individuals that have the disease and those who don't, and compare their whole genomes, to identify differences.
Gabriel Hua - Wootton High School
What is so good about DNA day.
     Sarah Harding, M.P.H.: DNA Day is a great opportunity to connect science classrooms across the country to genetics. We take advantage of DNA Day to create new programs and products to help bring genetics into the classroom. This chatroom is our chance to find out what students are curious about in regards to genetics, and to give them answers from the top experts in the field!
Britney Green,Washington D.C
Why are the DNA bases named Adenine, Thymine, Cytocine and Guanine?
     Chris Austin, M.D.: Those names applied to these chemicals for a long time, in fact long before it was known that they were parts of DNA as we currently know its structure. For many years, it was thought that DNA served a structural role and had nothing to do with heredity! The names are those given to them by chemists many years ago.
Alex Newton,MA
Regarding genetic sequencing in dogs: If a computer can analyze a dog's genetic sequence so far as to be able to tell what breed it is, could computers be used to distinguish the breeds/families that make up any given mutt's heritage, based on its genes?
     Heidi Parker, Ph.D.: In short, yes, we believe it can. We have been working for the last couple of years to come up with the appropriate equations to distinguish the breeds that make up a mixed dog and have seen some encouraging success. Look for more to come in the next year or so.
Claire, Thomas Wootton High School, Maryland
How well are science projects such as the Genome Project a national priority according to the political administration?
     Francis S. Collins, M.D., Ph.D.: There are many stresses on the administration at the present time, and science has not received as much emphasis as some of us scientists would have hoped! But in the field of biomedical research, the study of the human genome is considered by most a very high priority -- including Secretary Leavitt, who has championed efforts to emphasize research on genes, environment, health, and disease.
Koshland DNA Day participant
Is there any correlation between mutations in DNA and being gay?
     Vivian Ota Wang, Ph.D.: Behaviors are due to a number of genes and environmental factors interacting with each other, many of which have not been discovered yet or clearly described. Your question falls into this category. While some studies have begun identifying some gene changes associated with sexual orientation, it is too early to draw any conclusions from these preliminary studies.
Josh Lee
Is your job hard? What makes it that way?
     Barbara Biesecker, M.S.: Yes, it's hard in the sense that people often face difficult decisions in genetics clinics. However, it's valuable and rewarding work. It's a privilege to work with people struggling when you can help them.
Breyona Trent and from upper Marlboro MD
Why is DNA so important?
     Heidi Parker, Ph.D.: DNA carries all the information that a cell needs in order to survive and reproduce. It also contains all of the information needed to decide what kind of cell it will be and what kind of organism it will create.
jamona, Maryland
Why is DNA required?
     Phyllis Frosst, Ph.D.: DNA is the blueprint for every cell in our bodies. It's the instruction book that makes us, us! DNA also has the amazing ability to transfer information from one generation to the next, have any mistakes corrected and accumulate tiny changes that drive the process of evolution.
One and Only
Why do you do this job?
     Eric Green, M.D., Ph.D.: I have been involved in genomics and genetics research for the past 18 years. I cannot imagine a more rewarding and exciting area of biomedical research. Being involved in the Human Genome Project was a once-in-a-lifetime opportunity, and being part of that historic effort is something I will always remember. Now, the focus of my job is to direct research programs that aim to use the fruits of the Human Genome Project to advance our understanding, study, and eventually treatment of genetic diseases. Such a cause is quite compelling.
Kristen Afflack
Can you determine through genes how a baby will look and how smart they will be?
     Chris Austin, M.D.: No. How a baby looks of course is related to how their relatives look, and this is due to genes, but appearance is a complex combination of many genes so it's impossible to predict in advance. How smart a person will be is combination of a person's genes and the environment they grow up in, so even if we knew all the genes that affect intelligence (which we don't) we still couldn't determine in advance how smart a person will be.
Grace Hyun, Newton MA
How do you know so much about DNA?
     Belen Hurle, Ph.D.: I don't know that I know a lot about DNA , but I certainly enjoy learning about it. I like DNA because I like to know how things work. I first discovered genetics in high school and I was immediately attracted to it. As an undergraduate, I decided to become a biologist. Later , to enter a graduate program and became a geneticist. Each step along the way I read a lot about DNA and DNA technologies, and worked with mentors that gave exciting projects to think about.
chasity and im from uppermarlboro md
what is the purpose of dna day
     Sarah Harding, M.P.H.: DNA Day is the celebration of the completion of the Human Genome Project in 2003 and the anniversary of Watson and Crick's description of the double helix in 1953. Each year on DNA Day, classrooms get connected to genetics professionals to learn more about current topics in genetics, and to get informed about careers and other training opportunities.
frederick douglass highschool
Como Estas?
     Belen Hurle, Ph.D.: Bien y tu? Hey soy espanhola y acepto preguntas de todos los que hablan espanhol ahi fuera! preguntadme lo que querais!
Juan Jose, NM
Why would you choose a dog to compare the genome? Why not something else, say a three-toed sloth?
     Heidi Parker, Ph.D.: The dog is an interesting organism on its own not just as a comparison. But as a comparison to human it works very well as it represents a whole new clade of mammals. Even though it is further removed phylogenetically than the apes or the rodents, it actually shares much of its DNA sequence and genome organization with humans. Don't worry, we wont stop with dogs, many other organisms are in the works so the three-toed sloth still has a chance.
Ben Plotsky Wootton High School
There was news last fall that reported findings on a certain cluster of genes related to controlling some aspect of skin pigmentation. Will we hear more about the applications of this research in the future?
     Francis S. Collins, M.D., Ph.D.: You are correct, just a few months ago a gene called SLC24A5 was found to have a variant that is associated with light skin in Europeans. Our ancestors were all dark skinned -- this effectively means that Europeans are mutants! But that mutation apparently provided an advantage in northern climates, where dark skin can lead to rickets because of inadequate sunlight. No doubt other skin color genes will be found. This generates some controversy in some quarters, since it will ultimate make it possible to predict skin color from a DNA sample. But there will also be significant medical benefits from understanding this aspect of human biology. For instance, understanding skin color genes may help us come up with better methods to prevent and treat malignant melanoma.
St. Ignatius College Prep High School
What education is needed to become a genetic counselor?
     Barbara Biesecker, M.S.: Genetic counselors obtain a master's degree from an accredited program where they learn a great deal of human genetics as well as counseling skills. In college people who are interested in genetic counseling often double major in biology and psychology. Some people describe the profession as a form of medical social work. The work is very rewarding!
Dr. Steven Fine, Medical Arts High School, Camden, N.J.
What in your opinion is the biggest ethical, social and legal implication resulting from the human genome project?
     Francis S. Collins, M.D., Ph.D.: The need to prevent genetic discrimination in health insurance and the workplace -- a problem that is still not solved in the U.S.
Shivani, Uni of Leicester, UK
Can drugs alter DNA?
     Phyllis Frosst, Ph.D.: Interestingly, drugs can alter DNA. It's part of what makes some environmental toxins so damaging to our bodies. Some drugs can bind to DNA and alter its ability to be translated into mRNA and then into proteins, changing and in many cases damaging, its function. For more information of the damaging effects of so-called "recreational drugs" see the webpage of the National Institute on Drug Abuse at NIH at
How did people find out about DNA?
     Belen Hurle, Ph.D.: Friedrich Miescher, first isolated the white, slightly acidic substance from the nucleus of cells in 1869. No one knew what DNA's function was?in fact, some doubted that it had a function at all?so they pretty much left the stuff alone. But during the 1930s and 1940s, new experiments began to suggest that DNA might, in fact, be important. It turned out that different strains of bacteria can exchange DNA and that when they do certain traits, such as the ability to cause disease in humans, can be passed from one strain of bacteria to another. Scientists also learned that when a virus infects a cell it injects its DNA into the cell, which then produces many copies of the virus, suggesting that DNA contains instructions for building viruses.
Big Will From Maryland
What is RNA?
     Heidi Parker, Ph.D.: RNA is a molecule similar to DNA but with one change in composition, it uses uracil (U) instead of thymine (T). RNA is created from the DNA sequence through a process called transcription.
Matt Vertescher, Newton MA
Do you think the future could end up as seen on the 1997 film "Gattaca"?
     Francis S. Collins, M.D., Ph.D.: I hope not!!!! If we all decide to sacrifice our civil rights on the altar of genetic determinism, as they did in GATTACA, we will have both made a horrendous scientific error (genes aren't everything, environment really matters) and an even more horrendous social error (ignoring free will and the importance of human motivation and spirit).
Shivani, Uni of Leicester, UK
Is there a cure for Adrenoleukodystrophy? How far are along do you think they are in curing the mutation in the gene?
     Chris Austin, M.D.: From the fact that you know what ALD is, you undoubtedly know that it's a metabolic defect we know a fair amount about in terms of basic biochemistry, but the exact mechanisms by which the known genetic mutations lead to the clinical manifestations of the disease are less clear. In terms of curing the mutations, this gets into the realm of gene therapy, which is being worked on for ALD but it will realistically be a decade or more until these approaches come to clinical application. More promising for treatment is that the knowledge of the genes involved in ALD are providing new drug targets that can be explored to develop new treatments.
Steven, Hartford
Why did you decide to start studying DNA, and did you use any helpful equipment?
     Eric Green, M.D., Ph.D.: I am trained as a physician (pathologist) and a scientist. I got involved in genetics and genomics research because of my belief that a better understanding of patients' genetic blueprints would provide new opportunities for diagnosing and treating genetic diseases. I remain convinced this is true. In terms of helpful equipment-- genetics research involves the use of a remarkably diverse set of instruments and tools. Robots, lasers, computers, microscopes, sequencing machines, centrifuges-- way cool equipment!
Brown Middle School, Newton MA
Where is the most research being done into the human genome?
     Francis S. Collins, M.D., Ph.D.: Many countries are involved, especially Japan, China, Canada, and the United Kingdom -- but the U.S. has the largest investment. In the U.S., genome research is done in dozens of institutions, funded by the National Institutes of Health. Particularly large genome centers are in Boston, St. Louis, Houston, and Seattle. There is also a major genome research center here in Bethesda, MD -- focussed particularly on medical applications.
Ben Plotsky-Wootton High School
Is it possible to identify a certain base sequence that would correspond to a certain trait?
     Phyllis Frosst, Ph.D.: It certainly is. We can test for specific disease-causing genetic changes so that we can better determine treatment options. It's also possible to identify multiple sequences that correspond to a certain trait.
J Watklevicz New York
Can DNA be used in weapons of mass destruction?
     Francis S. Collins, M.D., Ph.D.: Yes, in the sense that biological weapons would all depend on engineered infectious organisms, and all such organisms have genomes of DNA and/or RNA.
Steve Brown, Marshfield
Que es hoy el dia de DNA?
     Belen Hurle, Ph.D.: Hoy celebramos el descubrimiento de la estructura del DNA en Abril de 1953 y el final del projecto genoma humano en Abril de 2003. !En tan solo 50 anhos el progreso de la genetica ha sido enorme !Cada anho aprovechamos el dia del ADN (25 de Abril) para que todos los estudiantes de bachillerato del mundo se interesen por el DNA y nos pregunten lo que quieran. Gracias por preguntar en espanhol!
How do genes turn on and off?
     Carla Easter, Ph.D.: This is a question is about gene regulation. There are regions in the DNA know as regulatory regions, and they are usually, but not always at the beginning of the gene. "Regulatory proteins" bind to these regulatory regions. Those proteins that intiate the turning "on" of the genes are known as activators and those that turn "off" the genes are known as repressors. The result is that when a gene is turned on, it produces a gene product and when it turned off, it does not.
Max Posner Newton MA
How is genetic counseling useful in the case of psoriasis and arthritis?
     Barbara Biesecker, M.S.: If there is a significant family history of psoriasis or arthrits (or both), genetic counseling can be useful. Even without the availability of genetic testing for common conditions such as these, counselors can help people understand what the chances are for recurrence (for relatives to be affected). These conditions may have a significant negative impact on one's quality of life that counselors can help address. Further, counselors can help with resources and referrals.
Dr. B.B.S.P.Nag, SMV Centre for Biotechnology, NAGPUR, INDIA
Have any other animals, such as fish, had their genome sequenced?
     Heidi Parker, Ph.D.: Yes, we have sequence available from a number of animals including at least 2 fish (the puffer fish and the zebra fish) as well as the sea urchin.
D. Percoco, New York
17. Will DNA fingerprinting techniques used more regularly in courts of law open more doors for discrimination of certain groups? Allow for easier abuse of the technologies and misleading interpretations for the juries?
     Vivian Ota Wang, Ph.D.: While DNA technology is being used more regularly in the courts, some people believe that its increased use will unjustly identify and discriminate against members of certain groups. While there are examples where this has occurred, the technologies have also exonerated people who have been previously convicted. Because DNA "fingerprinting" can be complicated to explain, this only makes it more important that it is described clearly to prevent misleading and/or inaccurate interpretations.
St. Ignatius College Prep High School
Que es el ADN?
     Belen Hurle, Ph.D.: Es la molecula con todas la informacion necesaria para crear un organismo vivo. Todas las plantas y todos los animales tienen su propio DNA, su manual de instrucciones individual. Es tamben la molecula que transmite la informacion genetica de una generacion a la siguiente.
DNA stands for Dinosaur Nose Acrobatics, right?
     Phyllis Frosst, Ph.D.: An acronym can stand for whatever you would like to use it for in any specific context. Distracting Nerds with Access to the web, for example. In the context of genetics and genomics, DNA stands for Deoxyribonucleic acid.
kasia phillips, co-op city, the bronx
Are human genetics completely understood yet?
     Chris Austin, M.D.: Not at all! In fact, this is a great time to get into the field of human genetics, because there are such great opportunities to begin to understand how particular genes relate to human function and disease. Thanks to the Human Genome Project, we have the whole "parts list" of human development and function. But the real challenge is to figure out what all these genes are doing, and how they go wrong to cause disease. We know the function of less than 10% of the genes in the genome, and know even less about how these relate to common diseases and how to fix the problems they cause. So learn about genetics and join us!
Makarai Stone, Upper Marlboro, Maryland
En que paises se celebra este dia?
     Belen Hurle, Ph.D.: El 25 de Abril de 2003, el congreso de los Estados Unidos decidio que el 25 de Abril es "DNA Day" .Yo creo que el primer dia solo los estudiantes americanos lo celebraron, pero en los ultimos 4 anhos hemos recibido preguntas de Asia, Europa y Sudamerica! todos los paises estan invitados a celebrar DNA day!
What are the current advances in gene therapy for Cystic Fibrosis?
     Francis S. Collins, M.D., Ph.D.: Since the CF gene was found by my research group in 1989, there has been a huge amount of interest in development of a gene therapy approach -- since inserting a normal copy of the gene into all of cells of the airway of a child or adult with CF could be curative. But this has been a very difficult challenge -- the methods that have been used (adenovirus, adenoassociated virus, lentivirus, and non-viral methods such as liposomes) have sometimes provided brief evidence of benefit, but not in a sustained way. But there are new ideas every year -- and meanwhile the development of new drugs for CF is also moving along in a very rapid fashion. Best of all, survival in CF is getting better each year -- now 36.8 years, whereas it was less than 10 years in the 1950s.
Lindsey Couture
What makes twins?
     Dale Lea, R.N., M.P.H., C.G.C: Twins can be identical (have the same DNA make-up) or fraternal (different DNA makeup). Identical twins come from the same egg and sperm which breaks in in two after fertilization. Fraternal twins come from two separate eggs -- just like a brother and a sister in separate pregnancies -- but fraternal twins develop in the same pregnancy.
Delaisa Jackson for Doulass
How is DNA related to colorblindness?
     Chris Austin, M.D.: There are a variety of kinds of colorblindness, and each is caused by a mutation (difference in DNA sequence) in a different gene. In general, these are genes that code for the proteins in the back of the eye (the retina) that allow us to see one color or another. There are 3 color "opsin" genes, and mutations in any of them can cause color blindness.
Kayla Morgan
What exactly is DNA and how does it control what I look like and what diseases I have? Why is it so important and if I lose a finger can't DNA just replicate it back?
     Heidi Parker, Ph.D.: DNA is a molecule found in almost every cell in every living organism. It contains information needed for the cell to grow and reproduce as well as information that tells the cell what role it will play in the organism. Only some cells, called stem cells, retain the ability to use all of the information and build any part of the body. If you cut off your finger, the other cells in your hand will not be able to grow another finger because they only know how to be hands. Some organisms (such as types of lizards and fish) can grow back body parts. Scientists are studying these organisms to find out how they do it.
Allison- Everywhere and Nowhere
What is the difference between genetics and genomics?
     Francis S. Collins, M.D., Ph.D.: Two letters! No, seriously, genetics is generally considered to be the study of individual genes and their effects. Genomics takes a more global attitude -- looking at the whole DNA instruction book at one time.
Sarah Holmes Liberty, MO
How long have you been studying DNA?
     Belen Hurle, Ph.D.: Ciao! I think you are our first person from Italy ever. Four years in my graduate program, and about seven years after my PhD. But I started reading books and articles in Scientific American long before, when I was in high school. Do you like DNA?
Olivia, Italy
Will finding out the sequence of human genomes help us to prevent diseases and actually do anything about it relatively soon?
     Francis S. Collins, M.D., Ph.D.: It's already happening! For example, in families with several persons who have been affected with colon cancer, it is possible to carry out a DNA test and find out who else is at risk. Knowing you're at risk can save your life -- having colonoscopy once a year in this high risk situation and detect and remove small growths before they become malignant. The same opportunity will exist for more and more diseases in the near future.
claire godfrey
Where do Attention Deficit Disorder and Attention Deficit Hyperactive Disorder come from? Are these disorders genetic?
     Barbara Biesecker, M.S.: ADD and ADHD are considered complex conditions caused by genetic as well as environmental factors. They can cluster in families meaning that some families may have more than one affected person. But most often we don't consider them inherited. By this we mean that there are not high chances for someone with ADD or ADHD to have a child or sister or brother with the same condition. When there are families with many relatives affected, that suggests that there may be more of a genetic contribution and higher chances that other relatives will be affected. You could consider these conditions genetic in the sense that genes do contribute to them. We cannot generally control whether or not someone will be affected. But the signs of ADD or ADHD can often be treated with relative success.
casey and lisel from Sacred Heart Academy
Can animals inherit genetic disorders?
     Heidi Parker, Ph.D.: Definitely, animals are just as susceptible to genetic disease as humans. In animal populations that are very small, such as endangered species, the risk of genetic disease is even greater because of the lack of variation in the gene pool.
N. Duetsch, New York
Where can you find dna on your body?
     Belen Hurle, Ph.D.: In every single cell, except in red blood cells and eye lens cells.
shannon donlo, stanfprd, connecticut, 54 carter drive
How do they perform a genetic test?
     Barbara Biesecker, M.S.: There are several different types of genetic tests - DNA analysis, chromosome analysis, metabolic/biochemical testing - for example, and the techniques for each are different. Genetic testing usually involves taking a blood sample, a skin sample, a cheek swab, and then purifying the genetic material you wish to test.
olivia Newton
how many chromosomes are in a full DNA?
     Carla Easter, Ph.D.: This questions refers to the number of chromsomes in an organisms genome. This depends on what species' "full" DNA you are referring to. Humans have a total of 23 pairs of chromosomes. Chromosomes in humans are numbered. Chromsome Number 1 is the largest and Number 22 being the smallest. An interesting side note is that a camel has 35 pairs, crabs have 104 pairs, tomatoes have 12 pairs, and house flies have 6 pairs of chromosomes.
sophie and Svetlana from Sicily and the Ukraine
We have been discussing genetic engineering and transformations and have learned about ANDi, the transgenic monkey. Can you explain why ANDi does not glow green under UV light? How do scientists know if he carries this gene? Is he a healthy monkey? Thanks for your help.
     Phyllis Frosst, Ph.D.: ANDi the transgeneic monkey illustrates one of the fascinating features of our genome and how we use it. The gene for Green Fluorescent Protein (GFP) was transgenically inserted into the egg that would go on to develop into ANDi, however it was not possible to control where the gene integrated into his genome. As a result of this, ANDi expresses the green protein only in cells where that gene is expressed, based on the regulatory sequences that suround it. Scientists can look for the presence of the gene by techniques such as PCR. And you'll be glad to know that ANDi was born a healthy, active monkey.
Biology B Class, Staples High School
Donde se estudian el DNA?
     Belen Hurle, Ph.D.: Nosotros estamos en Los Institutos Nacionales de la Salud , en Bethesda MD, muy cerca de Washington DC en los Estados Unidos. Pero el DNA se estudia en todos los lugares del mundo! Particularmente los datos electronicos del proyecto genoma humano pueden accederse gratis desde cualquier computador del mundo.
Maru, CT
how do you identify the identity of a person from dna
     Francis S. Collins, M.D., Ph.D.: Each of us has a completely unique DNA sequence (except for identical twins, who have the same). Thus a DNA sample from a suspect, tested in the laboratory and compared with a sample collected at the scene of a crime, can make a match that is 100% accurate. This is being used now in lots of criminal cases to identify,or exonerate, the accused culprit.
Jason newton mass
What courses in college do you have to take to have a job like yours?
     Barbara Biesecker, M.S.: My position is genetic counseling. In college folks who want to pursue genetic counseling in graduate school take courses in biology, genetics, and psychology. We also recommend that they get volunteer experience counseling people in various settings. It' a great career!
otilia, newton
Who was the first person to finish the human genome and did they win a nobel prize?
     Francis S. Collins, M.D., Ph.D.: No Nobels yet. The human genome sequence was finished 3 years ago (that's why we have DNA day in April!), but it was done by a team of more than 2000 scientists working in six countries. I had the privilege of leading that team. The genome is our shared inheritance, so it's rather nice that it was done by scientists all over the world, who all agreed to give the data away for free on the internet.
mordacai, montana
Is DNA fun???
     Dale Lea, R.N., M.P.H., C.G.C: Yes, it is lots of fun! DNA, the field of genetics and genomics is exciting in that it promises better ways to diagnose, treat and prevent common and rare diseases. It is also really cool because it shows how we evolved; how we became to be humans; and the relatedness of life back through time.
Ryan Guatemala
Hola como estas. Tengo una pergunta para usted. Que es la RNA y es lo mismo que al DNA?
     Belen Hurle, Ph.D.: El RNA y el DNA estan relacionados pero no son la misma cosa. El DNA es el libro de instrucciones que nunca sale del nucleo de la celula. Es la "copia de seguridad" que contiene toda la informacion de la celula. Cuando la celula quiere producir una proteina particular, hace una copia del gen en question en la forma de RNA. Puedes pensar que el RNA es una fotocopia de una pagina del libro. El RNA viaja del nucleo al citoplasma de la celula donde es usado por un complejo de proteinas, el ribosoma, para ensamblar la proteina deseada.
When was DNA day first started?
     Sarah Harding, M.P.H.: DNA Day began in April of 2003, with the completion of the Human Genome Project. It also marks the anniversary of the description of the double helix in 1953.
Kasia Phillips, Co-Op City, Bronx
What is your favorite genetics movie?
     Francis S. Collins, M.D., Ph.D.: I'm still waiting for one that I would really like! GATTACA had a lot of interesting points, but it made genetics seem really scary. Jurassic Park had a cool segment on how to recover DNA from ancient materials (like an insect embedded in resin), but we all know that didn't turn out very well! The problem is that Hollywood likes to make movies that have good guys and bad guys, and the scientists don't usually get to be the good guys. Maybe you could make such a movie someday? I'm available!
Alex & Mallory, Cape Elizabeth, ME
What is the most effective way to determine what a specific part of the genome does?
     Heidi Parker, Ph.D.: I don't know about the most effective but here are a few option: Start with a sequence comparison between your section of the genome and matching regions of other genomes and see what has been learned about those. Also, look for genes in the region and see what they do and find similar genes that might have the same function. If this doesn't provide information you will need to experiment to find the answer. This could include mutation analysis in cell line or labratory organism such as yeast or fruit fly. You can also try to introduce the DNA into a bacteria and see if it produces new functions.
Ben Plotsky Wootton High School
Can people take your DNA and copy it?
     Dale Lea, R.N., M.P.H., C.G.C: That is an interesting question, and it's really focussed on whether it is possible to clone a person or not, especially cloning you without you knowing it. Fortunately, the answer at this time is absolutely not. Technology has not advanced to that point, and certainly without you knowing it.
Brendon Newton MA
If parents want their child not to inherit a certain gene, such as one for hair texture or hair color, is that possible?
     Barbara Biesecker, M.S.: No. When a child is conceived each parent contributes half of their DNA to their child But the distribution of genes from each parent is random and not something that can be controlled. You will hear stories about people who used artificial means of conceiving children who are not affected with a genetic condition that exists in their family. This is a rare use of relatively esoteric and expensive technology and is not used for chosing traits in a child. Further, traits such as hair texture or color are determined by many genes and environmental factors so chosing a gene mutation through artificial technology would not be feasible.
royse upper marlboro md
Can genetics control one's personality?
     Vivian Ota Wang, Ph.D.: To answer your question, sort of. Personality traits are a complicated mixture of genes and environmental interactions which include physical, social and cultural factors. While some genes have been identified as being associated with some traits, this is only the beginning in understanding a process about how genes and environmental factors interact in developing a person's personality.
Jeffrey Soffer Wootton High School
The gene for diabetes is located on many different chromosomes, so what possible steps can be taken to find a gene therapy for diabetes as it is also a multifaceted disease?
     Francis S. Collins, M.D., Ph.D.: Good question -- there are probably more than a dozen genes for adult onset diabetes (the most common type), though we only know for sure of about three right now. But there is a good chance that these genes will fall into certain pathways, rather than being totally disconnected. If that's so, a gene therapy directed at that pathway might have promise. But delivery of the gene to the right tissue (pancreas? muscle? liver? fat? we don't know yet) might be a real challenge. So many of us think that the advances in therapy that come out of understanding diabetes genes will not be gene therapy per se, but gene-based drug therapy.
pooja tiwari, SMV Centre for biotechnology, Nagpur,India
Is everything that we see on CSI true?
     Dale Lea, R.N., M.P.H., C.G.C: The answer is that CSI is a dramatic television show that has been GREAT for raising public awareness about the power of genetics. But, not everything you see on CSI is exactly accurate - such as the amount of time it takes to analyze DNA.
mordacai, montana
Can crossing over occur between the X & Y chromosome?
     Carla Easter, Ph.D.: Yes, and it occurs during meiosis. Chimpanzees, humans, and mice are three mammalian species where crossing over between the X and Y chromsomes has been detected.
What is the most common genetic disorder affecting humans today?
     Francis S. Collins, M.D., Ph.D.: Aging! Well, you might be surprised by that response -- but clearly there are genes for aging, and clearly we are all affected! As far as disorders that are caused by a single gene gone awry, particularly common ones are von Willebrand disease (a mild bleeding problem, affects about 1% of us) and Factor V Leiden (a predisposition to clots, affects about 6%).
Josh Jarriel
How long will DNA last once you die?
     Belen Hurle, Ph.D.: Last year, a research group isolated genomic DNA from a tooth of cave bear that was 40,000 years old! another group has isolated DNA from mamooth as well. In general it depends on the environmental conditions, such as heat, humidity and so on. Mitochondria are the power factories of the cell, and have their own DNA. Mitochondrial DNA decays slower than nuclear DNA, because there are more copies of mitochondrial genomes per cell.
solomon newton MA
How do homologous chromosomes pair up during meiosis?
     Heidi Parker, Ph.D.: Homologous chromosomes pair based on the similarity of sequence between them.
D. Lawrence, New York
How close is the DNA of a human to the DNA of a peanut?
     Phyllis Frosst, Ph.D.: Well, the peanut genome is only 2800 megabases, compared with the three billion bases of the human genome, so we're not going to be as similar, say, as humans and chimpanzees. We no doubt share many of the same genes that control cell process such as DNA repair, protein synthesis etc.
Kayla Morgan
If both parents have a genetic disorder that they might pass on to their child, is there a way to prevent the disease from being passed on?
     Barbara Biesecker, M.S.: Yes. It depends on how the genetic conditions are inherited and whether they are the same or different. Even conditions that have the highest recurrence risks (50%) may not be passed on to a child. It's important that a genetic counselor understand that conditions that the parents have and then they can answer your question more precisely.
What is your favorite part of your job? When did you decide you want to be a geneticist?
     Dale Lea, R.N., M.P.H., C.G.C: I am a nurse genetic counselor, and I have been working in clinical and educational genetics for the past 20 years. My favorite part is helping people learn and understand about a particular genetic condition in their family, and providing support and care to them throughout their life. I have written two books on genetics for nurses and I loved that part of my job as well. I got into genetics because I have a family history of a genetic condition.
James Fortin, Maine
What does DNA really look like?
     Francis S. Collins, M.D., Ph.D.: Because it is so small (the bases are separated by only 3.4 Angstroms), it is VERY hard to actually see DNA, even with the highest powered electron microscope -- the images look quite blurry. But despite that, we are quite sure that DNA is a double helix, as Watson and Crick published in Nature on April 25, 1953 (that would be 53 years ago TODAY!). Dried DNA looks like cotton. DNA in liquid solution is clear but viscous -- most people say it looks a bit like clear snot, but being a famous genome scientist I would never use such a disgusting comparison!
Matt Nguyen Oakes, South Africa
What is a genome?
     Belen Hurle, Ph.D.: A genome is all of a living thing's genetic material. It is the entire set of hereditary instructions for building, running, and maintaining an organism, and passing life on to the next generation. There is one nuclear genome, and several hundred mithocondrial genomes per cell.
Alexj, Germany
What is the most important thing I should learn today from this experience.
     Sarah Harding, M.P.H.: Our hope is that students will learn some fun facts about genetics, including that DNA is a fundamental building block of life. In addition, we hope you will learn about some great resources you can use to learn even more about genetics and opportunities available in the field.
Sean, south fork highschool
Do you think that the human genome project will assist us with environmental pollution concerns?
     Francis S. Collins, M.D., Ph.D.: Yes! Part of the problem we have right now is trying to decide what substances are toxic, and at what levels. But since we are different people, there's not just one answer to that, so that data is often conflicting. If we could combine information about environmental exposure and genetics, we could probably do a much better job of identifying which exposures matter and which don't.
Jamie, Crawfordsville, Indiana
What does DNA tell us about the fact that animals have hair all over their bodies and humans do not?
     Heidi Parker, Ph.D.: Hair growth patterning is controlled genetically much like hair or eye color. Humans do have hair all over their bodies, too, it is just lighter on the body than on the head. If you look at different people you will see that some have mnore hair than others. There are also animals that have very little hair like the naked mole rat and some breeds of dog.
Johnny, Crawfordsville, Indiana
What is the relationship between genetic variation and cancer progression?
     Chris Austin, M.D.: Genetic variation affects cancer progression at two levels: first, genetic variation in the genome the person was born with, and genetic variation in the cancer itself. There are mutations in the person's inherited DNA, such as in the genes BRCA1 or APC, which increase the likelihood that a person will develop a cancer or have it progress rapidly. These mutations are inherited -- that is, present at birth. I suspect what you may be thinking concerns the other kind of genetic variation in cancer, that is, in the cancer itself. Cancers start with a few mutations, which may have been present at birth or may be acquired during life from exposure to environmental agents (e.g., cigarette smoke), but once the abnormal growth starts, the cancer cells gradually and progressively acquire new mutations, and the cancer progresses clinically as these mutations are acquired. These new mutations lead to increased growth and resistence to anti-cancer drugs. A new Cancer Genome Atlas project has been started by the National Human Genome Reseaerch Institute and the National Cancer Institute, to fully sequence a large number of human cancers at various stages of progression -- this project will fully answer your question. Stay tuned!
Maia Stamieszkin from Cape Elizabeth, Maine
Does having a brother with autistic tendencies and other mental-health related issues put me at a greater risk of having an autistic child?
     Dale Lea, R.N., M.P.H., C.G.C: There are many causes of autism and it is not possible to say what your personal risk is based on having a sibling with this disorder. The best way to answer your question is for you to have genetic counseling when you are considering having children. A genetic counselor will review your family and medical histories and talk with you about genetic testing if it becomes available.
Adrienne Liberty, MO
What other species are most similar to humans in DNA?
     Phyllis Frosst, Ph.D.: We're the most similar to Chimpanzees, at 96% identity. We're the closest to other primates, as well.
Stanis Moody-Roberts, Cape Elizabeth Maine
Have scientist found a cure or treatment for Klinefelters?
     Barbara Biesecker, M.S.: Klinefelters is the condition where boys have an extra sex chromosome. There is no way to remove the chromosome as it is present in all body cells. However, if the diagnosis is made early enough, the boys are often treated with hormones in order to develop on target with their peers. Occassionally there are behavioral issues for some boys that make school harder and those may be treated with medications. In adulthood men with Klinefelter's often have lower fertility and may choose new technologies to assist them in becoming a parent.
John Smith From Alaska
What was the most difficult case of DNA dissorders that you ever discovered?
     Francis S. Collins, M.D., Ph.D.: Finding the gene for progeria (a dramatic form of premature aging) was a real challenge, because the disease never recurs in families. It took all of the tools and resources provided by the genome project to find the single misspelled letter (a T where there should have been a C) in the lamin A/C gene on chromosome 1. But it has made a huge difference -- we just found that gene three years ago, and this afternoon we will be having a major meeting to design a clinical trial for a drug therapy that looks like it might work!
otilia, newton
Are there any concerns now about how the gene research will affect our society in the future?
     Vivian Ota Wang, Ph.D.: Some people are concerned that genetic research will contribute to legal and social inequity. The Ethical, Legal, and Social Implications (ELSI) research program at the National Human Genome Research Institute addresses issues raised by genetics by supporting research and contributing to science policy. If you would like more information, please see an ELSI fact sheet at
Emma of Cape Elizabeth, ME
If identical twins have the exact same copies of their DNA, and they grow up in the same environment, why do they act so independantly and differently from each other?
     Dale Lea, R.N., M.P.H., C.G.C: Even though they are genetically identical and have shared environments, they still have different experiences that shape their personalities. Moreover, even though they are genetically identical, the way that they develop in the womb, may result in their brains being wired slightly different from each other and that can affect their personalities.
Carrie Liberty, MO
Can monkeys get genetic disorders?
     Heidi Parker, Ph.D.: Yes, monkeys can get genetic disorders. A genetic disorder is simply change in DNA that is passed down through generations and causes some change in the organism. So any organism that has DNA can get a genetic disorder.
Joshua Johnson, Washington DC
How big is the average genome?
     Francis S. Collins, M.D., Ph.D.: If you're talking about humans, it's 3.1 billion letters. Strictly speaking, it's actually twice that, since you get a copy of your genome from your mother and another from your father. Stretched end to end, this DNA would be 6 feet long, but it has to fold up compactly into every one of your 100 trillion cells!
Ort Gay
Who would you say is the most influential genetecist in the history of discoveries?
     Francis S. Collins, M.D., Ph.D.: James Watson and Francis Crick, though Mendel is a close second (or is that a third?)
Jack Mayof
How is DNA made?
     Phyllis Frosst, Ph.D.: DNA is replicated in dividing cells using cellular protein machinery, such as DNA polymerase. The process can be divided into the three steps of initiation, elongation and termination, from the 4 DNA bases and existing and DNA as a template.
If your son or daughter died, couldn't you make a clone of them from their DNA?
     Dale Lea, R.N., M.P.H., C.G.C: The short answer is no. The technology does not exist at this time to clone a human being. More importantly, would you want to? Plus even if you clone your deceased child, the resulting child would be different even with the same genes.
Tori, South Fork
If the slight differences in DNA account for the differences in our traits, how do we have a "human genomic standard" for comparison?
     Francis S. Collins, M.D., Ph.D.: The standard just happens to be the sequence produced by the Human Genome Project -- but it was actually derived from 5 or 6 people (anonymous volunteers in a Northeastern city). You are right, the differences between all of us means that there is no "normal" human genome sequence -- this is just a reference.
Christine, Newton, MA
Has anyone found DNA on Mars?
     Phyllis Frosst, Ph.D.: DNA has not yet been found on Mars, although there is evidence of liquid water, which suggests that life may have been possible on Mars.
Claire Liberty, MO
Do all animals have the same kind of DNA?
     Heidi Parker, Ph.D.: The DNA in all animals is the same kind, it is made of the same components and, for the most part, codes for the same genes. There are changes in the sequences, in the order of the genes, in the size and composition of the chromosomes and in a few speicific genes that allow you tell the organisms apart.
Why is there still so much debate about whether schizophrenia is a genetic illness?
     Barbara Biesecker, M.S.: Schizophrenia is a complex condition caused by both genetic and environmental factors. The debate related to schizophrenia is about which genetic markers are the ones most responsible for contributing to the cause. The debate was started by initial research that identified areas in the genome thought to contribute to the risk that could not be replicated. Some were disproven. This is indeed the nature of early genetic research. However, in the past five years or so, consistent progress has been made in identifying high risk genetic markers. So, there is no debate that genes contribute to the condition and that certain families have clusters of people affected or more relatives affected than would be expected if it was not genetic.
M. Ward - South Fork 14, Kincaid, IL
Are their any advances in the study of Fuch's Dystrophy?
     Chris Austin, M.D.: Although mutations in a particular gene (COL8A2) have been identified that correlate with, and apparently cause, Fuch's Dystrophy, there have been no major therapetutic advances yet.
Shannon Hudson, Crawfordsville, Indiana
What all do we know about the gene that causes diabetes?
     Francis S. Collins, M.D., Ph.D.: There are two types of diabetes: Type 1, or juvenile, or Type 2, or adult. Both have hereditary connections, but neither is caused by a single gene -- but rather by the combined action of multiple genes, most of which haven't been discovered yet. But they will be in the next 2 - 3 years, because of the Human Genome Project -- and that should help us develop much better methods of prevention and treatment.
Chris, Crawfordsville, Indiana
What does the term Genome mean?
     Phyllis Frosst, Ph.D.: The term Genome refers to the whole hereditary information of an organism that is encoded in the DNA. Check out a brief guide to genomics here:
Courtney, Illinois
If our genes evolved from monkeys, then why are there still monkeys?
     Francis S. Collins, M.D., Ph.D.: Good question! It's important to realize that at the same time humans were evolving, so were monkeys. Both we and chimps evolved from a common ancestor (which explains why our DNA is almost 99% identical to theirs) -- but we evolved down separate pathways. The common ancestor is no longer with us.
Kirstie, Illinois
Does grass have DNA?
     Carla Easter, Ph.D.: Yes. In fact, some grasses have more DNA in their genomes than humans. For instance, humans have 3000 megabases or 3 billion base pairs in their genomes. Rye has a genome of 8000 megabases or 8 billion base pairs and oat has 11300 megabases or 11.3 billion base pairs in its genome.
lewis newton mass
El oxigeno el capaz de danhar DNA?
     Belen Hurle, Ph.D.: Los radicales libres danhan el DNA de las mitocondrias. Que son las mitocondrias? Las mitocondrias son las pilas de la celula y producen toda la energia que mantiene la celula viva. Por desgracia, este proceso produce una alta concentracion de radicales libres. Aunque la celula es capaz de corregir automaticamente la mayoria del danho que se produce en el DNA del nucleo, el DNA de las mitocondrias no puede repararse tan facilmente. A medida que el tiempo pasa las mitocondrias se danhan y se paran y la celula muere. El organismo envejece.
Daniela Ponce, Chile
I want to contribute to the genomic biology how can I get an opprtunity to work with people like you?
     Francis S. Collins, M.D., Ph.D.: We need LOTS of smart people to work in the field of genomics. Have a look at!
pooja tiwari, INDIA
How long does it take to analyze DNA?
     Phyllis Frosst, Ph.D.: It depends on how much DNA you're analyzing. A standard run on a DNA sequencer available to most research labs can yeild about 600 base pairs of sequence in about 70-70 minutes. In a broader sense, many scientists make studying DNA their life's work.
mordacai, montana
What is the most inportant part of a geneticist's job?
     Barbara Biesecker, M.S.: Well, I am a genetic counselor and trained in clinical genetics. So for folks like me, the most important part of our jobs is to make sure that the diagnosis we make is accurate. All the information we give to people about what causes a condition and what the chances are for it to happen again depend on having the right diagnosis. Since there are not genetic tests available for all conditions, diagnoses are made primarily based on findings from good clinical exams by well trained geneticists.
Dick Bufu, France
Are cysts hereditary?
     Donna Krasnewich, M.D., Ph.D.: Some cysts are hereditary. For example, there are autosomal recessive and autosomal dominant polycystic kidney diseases, and the causative genes have been identified. Some of the affected patients also have cysts in their biliary ducts. There are also genes that cause cysts only in one region of the kidney, i.e., the medulla. However, cysts in the liver, for example, seem to occur in many of us and are seen on routine x-rays. These are probably incidental, and not related to any particular gene or genes.
Can anyone explain what Progeria is???
     Francis S. Collins, M.D., Ph.D.: Progeria is a very rare and dramatic form of premature aging. Kids with this condition appear normal at birth, but their growth slows, their hair falls out, and their skin starts looking aged. Their intelligence is normal, but their aging clock seems to run at about 10 times the normal speed, and they only live to about age 12, dying of heart attacks or strokes. But there is much excitement about this condition -- the gene has been found (by my lab), and we are about to start a clinical trial of a drug that shows considerable promise.
Alaina Hahn-Tualatin OR
Was the human genome completed in 2000 or 2003?
     Phyllis Frosst, Ph.D.: A "working draft" of human genome was completed in 2000 and the high quality genome sequence was released in 2003.
Mark (Sleepy Eye, MN)
What is gene imprinting?
     Chris Austin, M.D.: Imprinting refers to a variety of ways in which DNA is regulated in ways that are not due to sequence changes, but rather to chemical alterations in specific bases. The most common of these is adding methyl (CH3) groups to specific DNA bases, which leads to decreased expression (i.e., use) of the gene. It is called "imprinting" when it occurs in germ cells (eggs or sperm), and is passed on to offspring. Frequently imprinting affects only one or the other of the two chromosomes, and may affect only the mother's or the father's version of the gene.
catie, IL
What do you like about your job in genetics?
     Vivian Ota Wang, Ph.D.: What I like best about my job is being able to help people who are trying to make sense of genetic information (along with other environmental, personal, and social/cultural information) and what it means and doesn't meaning to them, their families and communities, etc.
Sade Wilson
My best friend likes salty foods, but I like "sweets" kind of girl. Do you think this is part of our DNA? Is there a sweet-lovers and salty-lovers gene?
     Barbara Biesecker, M.S.: How we taste food may indeed be determined by our genes. But this would be considered a complex trait determined by multiple genes. So, no there is not likely to be a sweet-lovers gene or a salty-lovers gene.
Zeetie, Arkansas

Information - Moderator We have some new genomic experts in the chatroom. Please welcome NHGRI Clinical Director Bill Gahl; NHGRi Deputy Director Alan Guttmacher; Shawn Burgess, an investigator in the Genome Technology Branch who uses zebrafish as a model; and Laura Lyman Rodriguez, special advisor to the NHGRI Director.

How close is our DNA to a dog's DNA?
     Heidi Parker, Ph.D.: Over all, the dog genome aligns with about 94% of the human genome. If you look at the sequences we are about 80-90% similar in the coding regions and much less in regions that do not code for genes.
CeCe, europe
Whose idea was it to start the Human Genome Project?
     Francis S. Collins, M.D., Ph.D.: There were a couple of people who proposed this in 1985, but most of the scientific community thought they were nuts. We now think of them as visionaries! Among them were Robert Sinsheimer (Santa Cruz) and Renato Dulbecco (a Nobel prize winner and cancer researcher). It took five years to get enough support to start the project, and even then a lot of people were against it, because they thought it would be impossible.
flannery Newton, MA
Is DNA hard to study?
     Phyllis Frosst, Ph.D.: Like all research and life in general, some days seem like a breeze and some days take a lot of effort. New tools and technologies are coming online all the time, making DNA research faster, more efficient and more powerful.
Cicily, South Fork, IL, USA
Is there anyway to stop the telomeres from aging in cloning experiments?
     Belen Hurle, Ph.D.: Telomere aging is a major issue in cloning experiments. It is also a major issue in normal biology. The problem in terms of cloning is that you use cells that already have shorter telomeres and they will continue to get shorter, for example Dolly only lived about ? as long a regular sheep because her telomeres started shorter than normal. Right now, there is no way to correct this problem. We have made a lot of progress in understanding the mechanisms of telomere regeneration, but we are not at the stage where we can really control length.
James pumpernickel-Fortin Puerto Rico
If a child has cancer, is it because of their parents' genes?
     Barbara Biesecker, M.S.: Cancer is a complex disease, caused by genes and environmental factors. Most childhood cancers are not considered inherited disease but there are exceptions. Very rarely there are single genes that contribute to cancer risk. So technically the parents may have contributed genes that made it more likely that the child got cancer but not to such a degree that it would be expected to occur in another child or in the child's children.
Laura, Newton MA
What effect does alcohol consumption have on your DNA?
     Barbara Biesecker, M.S.: Alcohol is not a mutagen. A mutagen is a substance that alters ones DNA. Alchohol kills cells, such as brain cells. But it does not change DNA.
Adam Friberg, Washington D.C
Is it possible to "cut out" a disease/ genetic disorder in a carrier?
     Bill Gahl, M.D.: Some carriers have signs and symptoms related to their genetic disorders (for example, with dominant diseases), while other carriers have no signs at all (for example, with recessive diseases). Nature itself will cut out carriers of genes that are fatal before the age of reproduction. However, new mutations then arise to replace the contingent of such genetic disorders in the population! As for artificially removing a genetic disorder in a carrier, we do not have the technology to do that now. There is a possible potential, however, in certain types of RNA that can bind to and inhibit only the abnormal allele of the gene. Someday......
A. Collins, New York
Are the DNA tests on TV acurate?
     Phyllis Frosst, Ph.D.: In principal, the DNA tests that you can see on TV shows like CSI and "Law and Order" are fairly accurate. Frequently, in order to advance the plot and make the show more fast-paced, the speed at which some tests proceed is exaggerated. I'm also told, that a big diference between life and TV (in this case) are the resources to perform as many tests as possible on as many cases as possible.
Madre Interesante
I have an internship at a lab in which transformed cell lines -NS0 cell cultures are used to produce protein pharmaceuticals. Because these cells are clones, they are supposedly genetically identical. As the millions of cells per mL multiply, is there a risk of mutation? I am aware that only a small part of their genome codes for the pharmaceutical protein, so the chance of the production of a detectable amount of defective pharmaceutical is extremely small, but a risk still exists, does it not? Are NS0 and other cell lines chosen partly because their polymerases are more successfull than those of other species? Do mammalian polymerases differ in their success in proofreading?
     Chris Austin, M.D.: Great question, and highly relevant to all of us who produce cells or proteins for research or therapeutic purposes. Since the cells that produce these proteins are living and replicating, they acquire mutations that could affect protein production. This is particularly true since what we are asking the cells to do is highly artificial -- produce a large amount of a foreign protein. As a result, very stringent quality controls are in place at biotechs that make these proteins to ensure that the protein is still the right one. However, the difficulties of doing this is one reason that generics of protein therapeutics have been so relatively difficult to make. In the lab, we see this phenonomen on a daily basis, where clonal cells display different behaviors not only within a passage but over passages. Cell lines such as N50s are usually chosen for their ability to produce large amounts of proteins, not for accurate proofreading. In fact, since these are all cell lines -- i.e., are immortal and go on dividing indefinitely -- they are highly unusual cells that are much more prone to mutations than regular cells in our bodies.
Caitlin Masterman -- Wootton High School
What is the genetic disorder that causes Asperger's syndrome?
     Barbara Biesecker, M.S.: Aspergers is a type of autism. Autism is a complex condition caused by genes and environmental factors. So technically Aspergers is not a genetic condition.
do you eat genetically modified food? do you like it?
     Alan Guttmacher, M.D.: I try to eat a balanced, healthy diet that is low in cholesterol. My diet certainly must include some genetically modified foods, since I pay no attention to whether the foods I eat contain genetically modified grains, etc. I have seen no data that suggest that genetically modified foods are at all dangerous to human health. The question of their impact on farming, etc. is a separate issue, of course.
Chelsey, Sleepy Eye
Can DNA be recovered from dinosaur bones, and if so could I have a dinosaur and if you could have a dinosaur what kind would you get?
     Shawn Burgess, Ph.D.: DNA has been recovered from a woolly mammoth, but as far as I know DNA cannot be recovered from dinosaur bones (there is no tissue left in a fossil). Even if you could get the DNA out, we can't use that DNA to make a "new" organism.
Bwwwennndannn like dinosaurs
What living organism has the largest genome?
     Heidi Parker, Ph.D.: According to the largest animal genome belongs to the marbled lungfish. However, there is an amoeba that has a genome 20 times that size and more than 200 times larger than the human genome.
Joshua Johnson, Washington DC
What is your favorite thing about the cell?
     Bill Gahl, M.D.: Compartmentalization. The intracellular organelles are separated from the rest of the cell by membranes, allowing for a specific environment that allows the organelle to perform its function. For example, the nucleus makes DNA and RNA and transports the RNA out to make proteins. The lysosome breaks down large molecules into small ones. These organelles have membranes that allow these functions to proceed. This is compartmentalization.
Chris Stokes Maryland
What would you want to study if you were not a genetic researcher??
     Alan Guttmacher, M.D.: Probably another area of medicine, since it is particularly satisfying to do work that is interesting, intellectually rewarding (even exciting) but also directly benefits other people. If I had to choose one other area of medicine, it would probably be heart disease.
Can two parents who have a genetic disease have a child who does not?
     Barbara Biesecker, M.S.: Yes. It depends on what the parents have and how their conditions are inherited. It particularly matters whether the parents have the same condition. For instance, if both parents have achondroplasia (the most common dwarfing syndrome) there is a 50% chance with each child that the child will also have achondroplasia. There is a 25% chance that a child would get two copies of the gene mutation and be stillborn and a 25% chance that a child will be of average height. So even with conditions inherited in an autosomal dominanat manner, there is a chance that a child will not be affected.
alex newton. massachusetts
What is the Human Genome Project?
     Alan Guttmacher, M.D.: Hello Alex (Connecticut is a good place to be from - my wife is from Connecticut) - The Human Genome Project (HGP) actually "was," not "is." I say that because, technically it finished on April 14, 2003, when its ultimate goal - the sequencing of the DNA in the human genome - was accomplished. In fact, it was accomplished several years ahead of schedule, and below budget. The HGP was a truly international effort, including researchers and organizations from many countries, all working together to sequence the genome. Now that the HGP is "over," we have moved on to the even more exciting work of figuring out how the genome functions and how to apply what we understand about it to improve human health.
Alex and I'm from Connecticut
What is the easiest, fastest, and least expensive way to transfer DNA from one location (Lab) to another. Same question for storage of DNA.
     Phyllis Frosst, Ph.D.: The easiest way to send DNA is to place a drop of a DNA containing solution onto a piece of nitrocellulose paper and seal it from the air. It's stable for a long time, and very light. In terms of DNA storage, this works best in a minimum amount of buffer at 4 degrees, for example in a fridge.
can athletic ability be passed on through DNA?
     Laura Lyman Rodriguez, Ph.D.: Athletic ability is what geneticists call a "complex trait", meaning that many genes contribute to the observable "phenotype". So, multiple genes presumably with roles in muscle size, power, and maybe the chemical processes that control how fast muscle cells can recover between "activations" will be involved. In addition, an important aspect to keep in mind with many "phenotypes" (such as athletic ability) is that they are in fact the result of both genes and the environment. So, a large part of any individual's athletic skill is based on how much they exercise, how they eat, do they smoke, etc., and not purely the result of the genes that they inherit. Genes may provide a head start, but good habits will make the difference!
Sacred Heart Academy Varsity Softball Team
How does DNA get inherited?
     Belen Hurle, Ph.D.: DNA is in the form of a double helix. The two DNA strands have complementary information, like the positive and the negative of a picture. During cell division, the DNA helix chemically ?unzips?, and two new strands are formed from the half templates. This creates two molecules identical to the original DNA molecule. Each new cell inherits its own DNA copy.
Melissa Newton,MA
Since humans and chimpanzees are about 96% similar genetically, do they suffer from many of the same genetic disorders?
     Heidi Parker, Ph.D.: Though chimps do get genetic diseases they are not necessarily the same as human diseases. This may be that they simply have not been observed yet or it could be due to ancient mutations that differentiate chimps and humans.
Jane, Chicago
In your opinion, what area of genetics holds the most potential for future research?
     Alan Guttmacher, M.D.: That is a tough one, because so many areas have great promise. Among basic science areas, the most important currently are the ones that explain how the human genome functions. Also of great importance is genetics research that examines how individual variations in genes translate into health and disaese, and how to use knowledge about genetics to improve the health of all.
D. Lawrence, New York
What are your personal career goals?
     Heidi Parker, Ph.D.: I am going to keep doing science for as long as I can. I love my job and learn something new every day. What more can you ask for?
Molly Gridfoot, Chicago, IL
When the DNA Helicase breaks the bonds between the nitrogenous bases during transcription, is there a specific point where the helicase begins to break these bonds, or is it random?
     Phyllis Frosst, Ph.D.: DNA helicase does recognise a specific DNA sequence to make its cleavage. In the muchy-researched bacteria E.coli, this cleavage occurs at the "chi" site GCTGGTGG by the enzyme RecBCD which has helicase and nuclease activity.
Roberto Carozza, Washington DC
Do you think that changes in bipolar disorder based on demographic information speaks to a genetic basis for the disorder, or an environmental basis?
     Barbara Biesecker, M.S.: Bipolar is a complex condition caused by genes and environmental factors. If you are referring to the increase in diagnoses, this is explained by better access to psychiatric services as well as better criteria for what constitutes bipolar disease. The improvement in diagnoses probably does not represent a higher incident as opposed to better identification. The answer then would be that the changing demongraphic is due to environmental factors.
Maria Fitzsimmons, Chicago, IL
Do we have any diseases today that are not genetic?
     Alan Guttmacher, M.D.: Great question. I actually think every single disease has a genetic component - both in how it is caused and in how we as individuals respond to the disease once we get it. However, it is also true that every disease has non-genetic components - envirnmental influences, lifestyle choices (like diet and exercise), etc., that also play a role in both causation and response to disease. So, all health and disease is genetic, but none is entirely genetic.
Sara Lucas, Menomonee Falls High School, Wisc
How is DNA held together chemically?
     Phyllis Frosst, Ph.D.: DNA bases are covalently bonded along the sugar phospate backbone, and held together at AT and GC basepairs by hydrogen bonding.
Alejandra Johannsen, Rio de Janiero Brazil
What are some important facts that I should teach my students about DNA?
     Carla Easter, Ph.D.: Interesting. I guess it depends on who you are teaching and your own preferences. In my opinion there are several things worth knowing about DNA, but here are a few things that I think of. This is by no means the end all be all to the most important facts about DNA: 1. All living organisms have DNA 2. Every human is 99.9% genetically identical to any other human with respect to their genome sequence 3. DNA is very stable and can be passed from an individual to their progeny 4. Many disorders have a genetic and an environmental componnent 5. The DNA from any organism looks the same as the DNA from another organism and is made of the same bases. The difference lies at the molecular level or in the actual order of the bases 6. At some point, the DNA sequence of a person may be used to help not only detect disease but also to design "personalized" cures 7. DNA is the genetic blueprint for every organism 8. DNA is made of 4 bases: Adenine, Cytosine, Guanine, and Thymine 9. The entire human genome sequence was deciphered in 2003 and that is why we celebrate DNA Day 10. The field of genetics/genomics is incredibly interdisciplinary and provides many opportunities for students interested in science, technology, engineering, and mathematics
Shanaynay, Harlem
Does your DNA change over the course of your life?
     Barbara Biesecker, M.S.: Overall, no. But in each cell there are spontaneous mutations (changes) and activation of genes. So DNA is dynamic even though you are born with all the DNA you will have in your body cells throughout your lifetime.
Michelle, South Fork
who should have have the rights of my genome?
     Laura Lyman Rodriguez, Ph.D.: Your genome, like your finger prints, your retina scan, or your hospital test results, is intrinsicly part of who you are and you should always retain some "rights" regarding who else may have access to the information that it may contain. Much like other types of information, there may be many cases where access to your genome may be reasonable, and in fact make a lot of sense - for instance, your doctor. Important questions to consider as you think about how YOU feel about controling access to YOUR individual genomic information are what limits you would like imposed on any access, and how you might feel about the future potential information that is included in our DNA that we simply don't understand today.
Sean, kincaid
How did you find out that the DNA molecule was the form of a double helix?
     Belen Hurle, Ph.D.: The race to discover the DNA structure makes a very interesting reading. The people responsible for the discovery of the double-helical structure of DNA were Francis Crick, Rosalind Franklin, Linus Pauling, James Watson and Maurice Wilkins. It is somehow unfair that only Watson and Crick get world-wide recognition for this landmark discovery. Watson and Crick published the paper entitled ?A Structure for Deoxyribose Nucleic Acid? in ?Nature? on the 25th April, 1953. In 1962 Watson, Crick and Wilkins received the Nobel Prize in Physiology or Medicine. They proposed that the DNA molecule takes the shape of a double helix, an elegantly simple structure that resembles a twisted ladder. The rails of the ladder are made of alternating units of phosphate and the sugar deoxyribose; the rungs are each composed of a pair of nitrogen-containing nucleotides. In their Nobel lectures they cite 98 references, none are Franklin?s. Only Wilkins included her in his acknowledgements. Franklin died in 1958. The Nobel Prize is only awarded to living persons.
Are there any new findings on hemophilia?
     Bill Gahl, M.D.: Work continues to provide better therapies for the hemophilias. These disorders have been around for a long time, so much of the clinical knowledge has already been disseminated. An enormous benefit to therapy occurred a couple of decades ago with accurate testing for HIV virus in blood supplies, and testing for hepatitis has improved treatment even more. Molecular genetic diagnostics have also recently become available. Scientists are working on gene therapy, addressing the problem that a large amount of each missing "Factor" has to be supplied. Another avenue of pursuit is to make the missing coagulation factors in cells, so tha they don't have to come from humans. That is progressing. You might want to access the hemophilia pages on Go to Gene Reviews and search. Also, you might check the National Hemophilia Foundation.
Amanda Sleepy Eye MN
How does cancer affect your genes?
     Heidi Parker, Ph.D.: Cancer is a disease that causes cells to duplicate and divide uncontrolled. When this happens many of the usual checkpoints are bypassed and the division does not go as planned. Mutations are introduced, chromosomes don't segregate correctly, and there are often deletions and duplications of regions or even whole chromosomes. The cancer cells then have a very mixed up genome that does not allow the cell to function correctly.
Marvin, Washington, D.C.
I am interested in pursuing a career in science. Would you please tell me the usual breakdown of your daily day? Thank you.
     Alan Guttmacher, M.D.: One of the wonderful aspects of a career in science is that you can spend your day in so many different ways, depending upon what you enjoy. Some scientists spend all day in a "wet lab" doing experiments, while others spend all day at the keyboard, doing computational biology. Other scientists also do research, but do it out in the "field" - which could be in the middle of the ocean, in a remote forest, or even in an inner city neighborhood. Others spend much of their time teaching. I happen to spend my time doing a lot of administrative tasks, including figuring out what are promising new areas of research that we should pursue.
Tyler, Newton MA
How do you isolate strands of DNA?
     Phyllis Frosst, Ph.D.: It depends a little on what you want to do with it. From cells, you carefully break them open, make sure that there are nuclease inhibitors around to inhibit the proteins that degrade DNA and using a combination of centrifugation and filtration, isolate and precipitate DNA. You can do a version of this at home, if you'd like, and isulate DNA from a strawberry:
Tik Tok Mclaughlin, California
Have you discoverd any genes?
     Heidi Parker, Ph.D.: Yes, we have found more than 20,000 genes in the human genome. We don't know what all of them do yet but we are working on it.
Can you compare both human DNA and animal DNA?
     Shawn Burgess, Ph.D.: Absolutely! This is a very important technique in genomic science. By comparing DNA between species, we learn what is common among organisms as well as what is special for each species. It gives us a deeper understanding of evolution and what makes a gene.
Armand, Upper Marlboro, MD
What direct medical advances have occured from the results of the Human Genome Project?
     Alan Guttmacher, M.D.: Most of those advances are still a few years away - but only a few. After all, the Human Genome Project finished only three years ago, so it is still a little early to expect a lot of direct medical advances from it. Nevertheless, we are well on the way. For instance, just ten days ago, a gene was reported that plays an important role in obesity. Many other genes that play a role in diseases ranging from heart disease to diabetes, to schizophrenia, etc., etc. have been found, based upon the human genome sequence produced by the Human Genome Project.
Matthew Tennyson, Carver Magnet High School, Houston TX
What is it like to work with something you can't see?
     Belen Hurle, Ph.D.: In a way, I can "see" DNA, since I work with the electronic data stored in the electronic databases. If I type "insulin" in a search engine, the computer will retrieve the actual sequence of the insulin gene (AATTAACC and so on) for me to look at. It is pretty cool.
Ben from Newton Massachussetts
Is it possible to alter DNA?
     Phyllis Frosst, Ph.D.: It is possible to alter DNA, both deliberately and accidentally. UV rays from the sun cause damage to your DNA, this is one of the mechanisms that cause skin cancer. Smoking can also damage your DNA. Gene therapy is the technique by which we currently alter DNA in human beings. Clinical trials in gene therapy are underway for diseases like cancer, in order to make DNA changes for beneficial reasons.
chris, south fork high school
Have we located the gene responsible for Hirschsprung's disease at this time?
     Bill Gahl, M.D.: Hirschsprung disease is really a sign, that is, a physical finding. Sometimes it occurs by itself, and sometimes it occurs in association with a group of other physical findings; in that case, it is called "syndromic" because it is part of a syndrome. There are several (6-10) syndromes that Hirschsprung disease is part of. In addition, there are 6 known genes that cause isolated Hirschsprung disease, and these account for only 50% of the known Hirschsprung disease! That means there are a bunch more, yet undiscovered. (This reflects a very complicated process of putting ganglion cells in to our intestines.) If you want to know the names of the Hirschsprung disease syndromes or the names of the known Hirschsprung disease genes, go to, hit GeneReviews, and search for Hirschsprung's. You'll get more than you wanted to know!
Eric, Kincaid,IL
How long does it take for DNA to repair itself after UV mutations?
     Carla Easter, Ph.D.: Damaged DNA is repaired once the damage is detected. In fact, DNA damage can induce specific repair pathways. Once DNA damage is present, its removal may proceed wholly or partially by at least two well-studied mechanisms, photoenzymatic repair or excision repair. For more information check out This site has a very nice explanation of the repair mechanisms.
D. Percoco, New York
If i wanted to save my DNA, were could I do it?
     Phyllis Frosst, Ph.D.: Many kits exist through which you can store your DNA. Target sells the CATGee DNA storage kit on their website.
bwendan, laxtown
If you live a healthy life style and both of your parents carry the genetic disease (High Blood Pressure), will that still affect your life?
     Alan Guttmacher, M.D.: A great question. Actually, no one gene causes high blood pressure (HBP). HBP is caused by the complex interaction of many genes and non-genetic factors, such as exercise and diet. If both of your parents have HBP you probably do have an increased risk for developing it, so living a healthy lifestyle (not smoking, maintaining a healthy weight, exercising regularly, etc.) is particularly important - since doing so will lower your risk.
Carver Pham, Houston TX
How long is a DNA strand.
     Shawn Burgess, Ph.D.: The answer is different for different organisms. In a single human cell if you stretched out all 46 chromosomes, it would be 6ft long.
Could doctors one day write a mRNA that could be used to create a protein able to cure genetic diseases such as diabetes?
     Shawn Burgess, Ph.D.: Yes, in principle this can already be done, we know what is wrong in many genetic diseases and the changes necessary to fix them. The real problem is we don't really know how to get the genes back into the patient. This is the problem that gene therapy is trying to solve.
Christopher Dixon-Houston, TX
Could you please explain the concept of crossing over?
     Heidi Parker, Ph.D.: During meiosis, homologous chromosomes align based on sequence similarity and cross-over occurs. In cross-over, the two matching chromosomes will exchange portions by breaking and recombining with the other chromosome part. This promotes genetic diversity and is the reason why children are not exact duplicates of their parents.
Karli, Crawfordsville, Indiana
how should i study for a hard bio test!?
     Carla Easter, Ph.D.: My suggestions is to start early and study a little at a time. I kow that it is hard to cram for a bio exam because there is so much to learn. I would also suggest that you look over your notes and book every night after the lecture. Biology tends to build upon basic concepts. Once you know the basics, the rest gets easier. So if you have to cram, be sure you really understand the basics. Good luck!!!
Do you think that eventually health insurance premiums could be based on an interpretation of various aspects of one's genome? If not, what is being done to prevent this?
     Alan Guttmacher, M.D.: I notice that you are in the U.K. Because of the National Health Service, it is highly unlikely that this could come to pass for you. In the U.S., however, where health insurance is largely employer-based, it is certainly possible that, as our knowledge of how specific genetic variations, insurers could want to use this information to set rates. Many states in the U.S. already have laws to prevent this, and federal legislation to make it illegal throughout the U.S. has passed the Senate and is being considered in the House.
Shivani, Uni of Leicester, UK
I am interested in the science of bioinformatics, what are some key problems that are involved during scientists' studies?
     Belen Hurle, Ph.D.: It is great that you like bioinformatics because it is a very hot area these days. Think about the huge electronic databases with all the sequences of all the genes in many different organisms. For the most part, no human has actually made sense of most of the row data. This is because technology generates data faster than we can process it. These days you can build up an entire career in research without ever touching a pipet. So the sky is your limit: evolution, medicine, pharmacy, genes and environment....the possibilities are endless if you have a good question, and a good command of the many software tools available.
Erin Jones
Is it possible to destroy DNA like you can destroy cells?
     Heidi Parker, Ph.D.: Yes, DNA can be destroyed. UV light will break it into little peices. Dry heat and a variety of chemicals will destroy is as well.
boneifa, Illinois
Is it possible for parents to determine what genes their children inherit?
     Laura Lyman Rodriguez, Ph.D.: No, parents can not control how genes are inhertited for their children. In some very specific cases where a specific gene or chromasomal abnormality has been identified as the cause of a severe or lethal disease, there is technology available that can test embryos for that specific gene or abnoarmality. In these cases, parents may consider the use of in vitro fertilization combined with this additional technology, known as pre-implantation genetic diagnosis, and then make a choice to only implant the mother with those embryos that do not contain the gene of concern. This is a very interesting and complex area of bioethics because of the many issues involved and the very individual choices invovled with the determination of what is considered a "severe" disease.
royse upper marlboro md
What effects can gene therapy in a parent have on the genes in an offspring?
     Shawn Burgess, Ph.D.: For gene therapy, the correction occurs in the affected cells but not in all cells, so children would still inherit the mutated gene. This is usually only a problem if both parents are carriers of the mutation.
William Trotty, Houston Texas
Will prisons ever switch over to recording DNA fingerprints instead of actual fingerprints?
     Alan Guttmacher, M.D.: It certainly is technically possible to do that, and one's DNA "fingerprint" is both unique and less prone to scientific misinterpretation than are conventional fingerprints. However, DNA also does require more expensive and less widely avaialble technology.
Katie H. and Sam S
What's your favorite chromosome?
     Shawn Burgess, Ph.D.: The X chromosome is the most interesting to me. It has very complex regulation that corrects for the fact that males only have one X chromosome and females have two.
Why doesn't everyone look alike if we only have a 1 percent difference in our genes?
     Bill Gahl, M.D.: In a way, we do all look alike, and a lot different from, say, sheep. But I like to think of our variable appearances as related to pathways. Suppose it takes a pathway of 100 steps in development to make a nose. (It probably takes many times that.) If two people differ in just one of those 100 steps (i.e., 1% of the genes are different in the two individuals), the nose will look different. Now make a slightly different size of cheekbone, a slightly different color and shape of the eyes, etc., and you have two people who look quite different.
kara & angie
Does DNA kill people?
     Belen Hurle, Ph.D.: The DNA of another organism can kill you ( think of a deadly virus injecting its DNA into your cells) . A mutation in a critical position in your own DNA can also kill you.
Adam Friberg, Washington Dc
How is it possible that animals evolved from plants?
     Shawn Burgess, Ph.D.: Actually animals did not evolve from plants. Animals and plants evolved from a primitive organism that had basic charateristics of both animals and plants. Each "branch" (animals and plants) evolved from that original organism.
Noah, Newton MA
What direct effect has genetic research had on our lives today?
     Alan Guttmacher, M.D.: It is still early in the "genome era," so the direct effects of such research are relatively few today, unless you happen to be a biological or medical researcher, in which case it has probably transformed how you work every day. Other direct effects have to do with improved prevention, diagnois and treatment for a number of diseases, particularly forms of cancer. In the next decade we anticipate a huge increase in the number of people whose health and lives will be improved by our knowledge of the human genome.
David Farkas - TWHS
Before the discovery of DNA, proteins were thought to carry the genetic traits of an indivuidual. What was the basis behind that theory?
     Phyllis Frosst, Ph.D.: Before the discovery of DNA, proteins were considered as candidates for carriers of the traits of an individual. The first experiments to show that protein was not resposible for heredity were performed by Fred Griffith in 1928. He injected mice with a live strain of deadly bacteria, and all of those mice died. Then, he killed the deadly bacteria cells by heating them. Mice injected with these heat-killed virulent bacteria did not die. In another set of mice, Griffith injected a live non-deadly strain of bacteria, and these mice did not die, the result which Griffith expected. The surprise came when Griffith injected a group of mice with BOTH live non-deadly bacteria AND heat-killed deadly bacteria. In that group, some of the mice died. When Griffith examined those mice, he found live deadly bacteria in their blood. Griffith drew the conclusion that the genetic information in the heat-killed virulent bacteria survived the heating process and was somehow incorporated into the genetic material of the non-deadly strain to cause them to become deadly. But Griffith knew that heat destroys protein, so he suggested that the genetic material must be something else. However, his results did not specifically point to DNA as a possibility.
Roberto Carozza, Washington DC
please correct me if i am wrong but one gene can code for multiple proteins depending on the way the introns are cut out?
     Carla Easter, Ph.D.: This is correct. The process is referred to as "alternative splicing." The mRNA is transcribed and then the pre-mRNA is spliced and regions of the molecule are removed to create the mature mRNA which is then translated into a protein. One of the best examples of alternative splicing is found in the immune system.
Josh Hickman from William Monroe High School
Are there any conditions where half of the body has a different genotype then the other half? For example, is it possible for a person to have X and Y chromosomes in some of their body cells but two Xs in other cells?
     Phyllis Frosst, Ph.D.: A genetic mosaic is an individual whose body is built of a mixture of cells of two or more different genotypes. Conditions exist where individuals are partially XX and partially XY in the different cells of their bodies, for example xyTurners about which you can read more at
D. Lawrence, New York
How long will a sample of DNA last that if it is taken medically from a person and kept in a test tube?
     Heidi Parker, Ph.D.: If the DNA was extracted correctly (removing enzymes that can destroy DNA) and stored in the appropriate pH controlled buffer, it can be kept indefinitely in a -80 degree freezer.
Sara, westview high school, ca
Why doesn't everybody look alike if there is only a 1% difference in genes?
     Alan Guttmacher, M.D.: A great question. Particularly because it is actually only 0.1% of our DNA that varies between any two people. However, even 0.1% translates into 3 million diiferences between any two people's DNA sequences. Also, it is not only genes, but also other factors that make us look the way we do - which is why even "identical" twins often show small differences.
kara & angie
How is a chicken's genome similar to a human's?
     Shawn Burgess, Ph.D.: There are many, many similarities between the chicken genome and the human one. Most of the genes we humans have are also in chickens. It is a relatively small number of genes that cause the differences between chickens and humans. All the basics are similar.
Rebecca, Alexandria Virginia
Does DNA determine your life expectancy?
     Bill Gahl, M.D.: DNA does determine life expectancy in many ways. For example, there are serious genetic diseases that will almost certainly shorten a person's life. Some types of high cholesterol cause heart attacks and death at age 20. Liver disease can be fatal in childhood. Susceptibility to skin cancers, as in xeroderma pigmentosum, can result in death in the second or third decades. All these diseases can be caused by mutations in a single gene, i.e., DNA. Then there are genes that combine their effects to put people at increased risk for death. The diseases involved might be diabetes, high blood pressure, cancer susceptibility. In these cases, there is a smaller effect of each gene, but the total effect on lifespan is still substantial. If you want to take it even further, your DNA also affects your emotions and your psychological well-being. These can influence lifespan as well.
In your opinion, what is the worst genectic disorder?
     Alan Guttmacher, M.D.: How bad any disorder is depends upon who you ask. I have known people with genetic disorders that many would see as relatively minor, but who feel that the disease has a huge impact on their lives. Conversely, I have known individuals with very serious effects from their genetic disease who see it as not a big deal, and even see some benefits from having the disease.
wendellson, new york
What do you enjoy most about your job?
     Bill Gahl, M.D.: I see patients with rare diseases, and seeing those patients is the most enjoyable part of my job. These patients have often gone from doctor to doctor, unable to find one who knows about the disease. My professional life has been devoted to developing expertise in a few rare disorders, so when affected individuals come with questions I can answer, or say I don't know. Often people do not need a cure or even a good treatment; they need understanding. They need to know if their symptoms are part of the disease, or should be investigated as something different. That is very satisfying. I hope you will consider this vocation yourself!
Danny, CA
Can you fuse the Dna of two people?
     Shawn Burgess, Ph.D.: The simple answer is this is what happens when parents have a baby. You can also fuse cells in culture, but typically this is an unstable situation and the cells will rapidly fall apart.
W, Landman, New York
Will there be a transcript of this chatroom?
     Sarah Harding, M.P.H.: Yes, the transcript for this chatroom will be available at You will be able to read all of the questions answered throughout the day today.
Joshua Johnson, Washington DC
How do cells make accurate copies of DNA?
     Shawn Burgess, Ph.D.: We have a really good enzyme called DNA polymerase that is very good at making copies. It makes a mistake roughly 1 every 50,000 bases. After that, there is another enzyme that "proofreads" and corrects mistakes. Very few mistakes occur during replication.
Martin St. Louis, Tampa
How do you extract DNA from living organisms?
     Belen Hurle, Ph.D.: In the lab we use commercial kits to extract high quality DNA from just about everything. However, if you google Strawberry DNA extraction, you will easily find a standard protocol to extract (and see with you naked eye!) a huge amount of DNA from a strawberry or another piece of fruit. It takes less that 10 min., no blender or special reagents required!
Abby P. Westview High, S.D.
How can the Human Genome Project be applied to identifying and treating genetic disorders?
     Alan Guttmacher, M.D.: A great question. Unfortunately, I don't have the three hours available that it would take me to answer it fully. So I will mention a few of the may ways that the HGP can help identify and treat genetic disorders. First, by providing us the complete sequence of the human genome, the HGP has made identifying genes responsible for all genetic disaeses much, much easier and to do and has made the work go much quicker. Second, by helping us to understand the actual biological mechanisms by which specific genes cause specific disorders, it helps us find new ways to treat - and even prevent - many diseases. Third, by making it easier to understand how individuals vary in their response to specific medications, knowledge of the genome can lead to individualized and more effective use of medications.
Zach, Massachusetts
Why is patenting so controversial/problematic in the genetics industry and not in others??
     Laura Lyman Rodriguez, Ph.D.: To patent something it must be novel and non-obvious. One of the important questions in the genetics area is whether or not DNA, something common to all every living thing, is novel. Additionally, although in the past there have been patents issued for genes based on a company's (or individual's) "non-obvious" work to learn the sequence of the gene, as the Human Genome Project progressed it became increasingly clear that the basic sequence of DNA is readily apparent (and therefore obvious) through the use of technology. Many people now believe that the threshold required to establish novelty and non-obviousness for genetic patents should require a true demonstration of function and should not be something you can quickly deduct through available resources for gene and protein sequences or other molecular structures.
St. Ignatius College Prep High School
So do you see a lot of people come in with Krabbes disease?
     Bill Gahl, M.D.: Krabbe disease is a very rare disorder. It is a lysosomal storage disease with neurological symptoms due to an enzyme deficiency. We do not see patients with that here, but there are centers that see many such patients. At the University of Minnesota, there is a trial with bone marrow transplantation (for patients diagnosed very early). Other university centers also see Krabbe disease patients.
Brooklyne Watson,kentucky
is dna confusing
     Heidi Parker, Ph.D.: Actually, DNA the molecule isn't confusing, it is made up of four bases, adenine (A), cytosine (C), thymine (T) and guanine (G). These four bases create a code that can be used to build protiens or to signal to other molecules. It is the de-coding and understanding the DNA that may seem confusing but is also the most exciting part of DNA studies.
Rebecca Wethington Kentucky

Information - Moderator Now joining the chat room is Tim Leshan, senior policy analyst, Jeff Schloss, director of the genome technology program, and Jean Jenkins, the senior clinical advisor to the NHGRI director.

What animal has the closest DNA to humans?
     Shawn Burgess, Ph.D.: Chimpanzees are the closest known relatives to humans. There is about a 96% match between humans and chimps across the whole genome. There is a press release on this here:
Are there any professions in the genetics world that are disappearing as technology progresses?
     Laura Lyman Rodriguez, Ph.D.: Because of the rapid advances in technolgy and our understanding of genetics and genomics there are many professions within genetics that are changing, but I do not believe that any are disappearing. One of the fabulous things about pursuing a career in genetics (or science generally) is that the opportunities are always evolving and there are consequently always new and interesting things to learn and do.
Molly Gridfoot, Chicago, IL
What is your salary?
     Belen Hurle, Ph.D.: That is an important consideration when choosing a carear path. NIH has a career resource named LIFE WORKS ( where you can browse all science careers by salary, interest area, education required, or alphabetical order.
kelsey martin, kentucky lyon county
Is it possible for DNA to mutate on its own?
     Shawn Burgess, Ph.D.: Yes. The chemistry of DNA does very rarely mutate spontaneously. More common by far however is mutations caused by the environment. Sunlight, chemicals, radiation, etc. are the primary causes of DNA mutation.
Nicole, Westview High School
How many genetic disorders are there that we know of, to date?
     Bill Gahl, M.D.: The Online Mendelian Inheritance in Man (OMIM) database lists 16,741 known genetic disorders. The site divides them into genetic subtypes. And there are more yet to be discovered!
Considering the current state of genetics, how can it be used to cure genetic disorders in fetuses or young infants?
     Alan Guttmacher, M.D.: Today's use of genetics in these situations is mostly by using knowledge of the gene involved in a specific disorder to develop medicines or other interventions that treat the symptoms of the disease. Someday, the hope is to attack the errant gene itself ("gene therapy") to cure the disorder.
Hose Rodriguez, Ashburnham, MA
Is DNA found in mitochondria different from the DNA in a nucleus?
     Belen Hurle, Ph.D.: Absolutely . Mitochondria have a several dozen genes, mostly specialized in aerobic cellular respiration. We cannot survive without mitochondria. Indeed, mutations in mitochondrial genes are known to cause many different human diseases.
Andrea Castano
It is fun having your job? If so, what part is the most fun, and the least fun?
     Alan Guttmacher, M.D.: You betcha. I feel like a kid in candy store. Every day is different from the day before and every day has some surprises that I did not anticipate when I came to work in the morning. The most fun is that I get to work with bright people who work well together, and make me better than I would be otherwise. The least fun is the occasional time when people's egos get in the way...
Tyler from the city NEWTON
What is a typical day at work for you?
     Shawn Burgess, Ph.D.: I run a lab here at the NIH so my job is a mixture of many different things. I talk to the people working in the lab discussing their different projects. I do online searches of the scientific literature looking for new papers important to my work. I still do some "benchwork" where I actually perform the experiments, but this is becoming less frequent. We use zebrafish in our research so there is taking care of fish and setting up breedings. The exciting thing about scientific research is that it is continually changing as you make new discoveries.
Kristen westview high school
How does DNa coil up into such miniscule structures?
     Carla Easter, Ph.D.: If human DNA were lined up end to end it would stretch nearly two meters or six feet, so it has to be compact enough to fit into the nucleus of the cell. The DNA is packaged by wrapping it around proteins called histones, forming a substance called chromatin. Chromatin is then folded and placed into the nucleus of a cell.
Jennifer Le, San Diego,CA
Are any methods being developed that can prevent spinabifida?
     Bill Gahl, M.D.: Spina bifida is a type of neural tube defect, and these disorders occur during development. Studies have shown that providing folic acid during pregnancy can help prevent neural tube defects. For more information, you might want to check out the NINDS Spina Bifida Information Page.
Stephanie Carver Oliver;Houston,Texas
What inspired the "Human Genome Project"?
     Alan Guttmacher, M.D.: The realization that, if independent scientists tried to sequence the human genome, there would be much redudant effort, some ineffective efforts and wasted funding. It was clear to some -but not all - that a coordinated effort would be much more efficient and effective than a piecemeal effort. In the end, that coordinated approach proved successful, ending more than two years ahead of schedule and under projected budget.
Mattew Tennyson-Houston, TX
How can we make sure that people are not discriminated against because of what the DNA might code for?
     Tim Leshan, M.P.A.: One way to make sure DNA is not used to discriminate against people is to pass laws that prevent such practices. Many states have passed such laws and there are some federal laws that protect some of us from such discrimination. But in order for everyone be protected comprehensive federal genetic nondiscrimination legislation will have to pass. Such legislation has passed in the U.S. Senate, but it is still pending in the U.S. House.
Samantha, Crawforsville, Indiana
what is gel-electrophoresis?
     Jeff Schloss, Ph.D.: Gel electrophoresis is a laboratory technique that's used to separate molecules. You can use it to separate proteins, or DNA molecules, or RNA molecules. They can be separated based on different properties, such as charge or size. When we use gel electrophoresis for DNA sequencing, we are separating the DNA molecules by their size -- the number of bases in the DNA strand. Automated machines can now crank out millions of bases of DNA sequence every day.
Jeff from Maryland
How does cancer affect your DNA?
     Jean Jenkins, R.N., Ph.D.: There are a number of ways: in persons who have a family history of cancer there may be a predisposition or an increased risk of developing cancer because of a DNA glitch that is inherited from mom or dad. Only about 5-10% of cancers (such as breast/ovarian or colon) occur because of this predisposition interacting with lifestyle and/or environmental factors. We are learning a lot more about the other persons without such an inherited risk who also develop cancer. There is a national research effort (see to see more about the cancer genome atlas) where genetic changes that are found in cancerous tissue but not in normal cells will be determined. This information is already known for some cancers, like lymphoma, where the genetic changes can be used to determine the correct diagnosis, identify best treatment, and even predict treatment effectiveness. Cancer is basically cells that get out of control because something is not working well in the communication between the cells. Perhaps the cells are multiplying and the message to stop growing does not work because of a DNA glitch. There is a lot more information at about genetics and cancer.
Marcel ,MD
Has any headway been made with the treatment of the little boy names Sam, who has progeria? I remember Dr.Collins speaking of him at a recent biotechnology symposium.
     Alan Guttmacher, M.D.: From talking with Dr. Collins this morning, I happen to know that an important meeting is occurring this afternoon to consider new experimental therapies for progeria. So, we have some cause for optimism, for the first time in history, that we may be able to find a helpful therapy for progeria.
Curtis, William Monroe High School
Are genetic disorders/mutations common? And how often do they occur?
     Alan Guttmacher, M.D.: Yes, they are very commmon. All of us carry many, many genetic mutations. Of course, some are more important to health than others. But everyone has dozens of mutations that affect risk for disease.
Can a living organism not have DNA?
     Carla Easter, Ph.D.: It all depend on how you define life. Most living organisms have DNA as their genetic material. But if you think a virus is living, we would have to say that there are living organisms without DNA since we could find viruses with RNA instead of DNA as their genetic material.
Justin Suarez Westview
Does DNA affect how easily you can catch a cold?
     Alan Guttmacher, M.D.: Our genome affects our chance of developing any disease - but so do non-genetic factors. The common cold is actually not a very well understood disease, but there are certainly genetic factors that play a role - we just don't know yet what they are. Why don't you become a genetics researcher and figure it out?
Noah, Newton MA
Are we any closer to finding out for sure if BRCA1 mutations are really the cause of breast and ovarian cancer? I know that most studies point to yes (that is what causes it) but has it been totally proven?
     Jean Jenkins, R.N., Ph.D.: If an individual has a BRCA 1 or BRCA2 genetic mutation, we do know that they have an increased risk of developing breast or ovarian cancer. However, not everyone with such an increased risk develops cancer in their lifetime, perhaps because they have other genes that are protective, they utilize screening and prevention measures that are helpful to them, or other factors influenced their risk that we don't yet know about. About 5-10% people with breast cancer have an inherited risk because of a genetic glitch. You can learn more about this by visiting and visiting the section on genetics.
Kaylee, Michigan
Dr. Guttmacher, what hospital do you work at?
     Alan Guttmacher, M.D.: Hi, Kelsey - Right now, I see very, very few patients - the ones that I do see are here at the National Institutes of Health (NIH) in Bethesda, MD. Previously, I worked at hospitals in Vermont and in Massachusetts.
kelsey martin, lyon county , Ky
How long did it take to complete the human genome project?
     Alan Guttmacher, M.D.: The HGP officially started in October of 1990 and ended in April of 2003 - moe than two years ahead of schedule (and under budget)!
How are insurance companies lobbying to use genetic information?
     Tim Leshan, M.P.A.: For the most part insurance companies are not lobbying to use genetic information. But some people are concerned that genetic information will be used by insurers to determine eligibility for health coverage or to set premium rates. NHGRI thinks genetic information should not be used by health insurers because it does not predict disease, it merely helps determine someone's risk for acquiring a disease.
Koshland DNA Day participant
Hallo! How can I help all of my friends here in Zimbabwe celebrate on this special day?
     Sarah Harding, M.P.H.: We have a number of other online activities you can participate in for DNA Day. Take a look at the DNA Day website at and you'll see our brand new DNA webcast featuring Barb Biesecker, a genetic counselor here at NHGRI. Or you can watch the two webcasts developed for last year. If you have any questions from these webcasts, log back into the chatroom and we'll answer them for you.
Unpica, Zimbabwe
How many years will it be before we can send in a DNA sample and get our complete genome?
     Jeff Schloss, Ph.D.: Hmm. How much money do you have? For about $10 million you could do it today! It's a little hard to predict the future, but if you'll let me guess, I would predict that within 5 years, a person for whom there was a really striking medical need could get their whole sequence done. I think it will still be really expensive (maybe about $10,000 - $50,000), but some surgical procedures cost that much today. It's not unreasonable to expect that, 10 years from now, people could get their genome sequence for about the same cost of many routine diagnostic procedures.
Mike Hamilton Menomonee Falls High School, Wisc
How do you know which bases are A,C,T,and G? Is there a method of recognizing them, or is it obvious under a microscope?
     Belen Hurle, Ph.D.: Great question. These days we use fluorescent DNA sequencing technology to determine the sequence of a stretch of DNA. We use fluorescent dye labels - a different color for each of the four nucleotide bases. As the sequencing reaction progresses, a laser beam excites the fluorescent dyes at the tips of the sequencing products causing them to fluoresce. The process of reading the sequence of colors is highly automated. A computer easily transforms the sequence of colors back to sequence of letters.
Danny, Westview High school
How did National DNA Day start?
     Sarah Harding, M.P.H.: National DNA Day began as a celebration of the completion of the Human Genome Project in 2003 and the anniversary of Watson and Crick's description of DNA's double helix.
Krystal Bucknor,Los Angeles
I am interested in studying Human Genetics at a graduate school level (PhD). What are the differences between Genetics and Human Genetics PhD program? And where can I find out what universities or institutions offer these programs?
     Alan Guttmacher, M.D.: Genetics and Human Genetics programs are often quite similar, or even identical. The latter may have more of an emphasis on human health and disease than the former, but the difference is usually just a random variation in naming. You can surf the net to find out about programs or, if you are an undergrad, look consult either your professors or your college's career counselling office. One place to look on the net is And good luck - this is the golden age of genetics - I envy anyone who enters the field now.
Sean, Philadelphia, PA
Do you use humans in your experiments? What for?
     Jean Jenkins, R.N., Ph.D.: Humans are an important component to the research that helps us understand risk, diagnosis, and treatment of persons with a genetic disease. Basic research may be done on clinical samples obtained from humans such as blood or tissue samples. Clinical research may be done with persons at risk for a disease with a genetic component (such as hereditary colon cancer) to determine their interest in genetic testing. Clinical research may also be done with humans who have a disease that responds to a certain treatment designed specifically to their genetic molecular profile (such as breast cancer and herceptin). See more about clinical trials at
Kathryn , Kentucky
What sort of careers are associated with DNA study?
     Sarah Harding, M.P.H.: There are many different types of careers associated with genetics and DNA. Just sitting around the table now for this online chatroom, we have researchers, doctors, nurses, science writers, computer specialists, ethicists, lawyers, policy experts, and people with a public health background. Genetics is a very diverse field that needs people with different backgrounds and interests to get involved.
Brittany, Edna Highschool
What determines the size of a genome and why is it that smaller organisms often haver largers genomes than larger organisms?
     Jeff Schloss, Ph.D.: Simple answer is, we don't know. The smaller organisms that have larger genomes don't actually have more "information" (such as genes), but instead have something called repetitive DNA. This can consist of simple sequences that are repeated over and over again. We don't really understand the role of that repeated DNA; we think it may play a role in evolution or fitness, rather than in providing an "instruction set" for building and operating the organism.
ellie, washington dc
Mrs. Jean Jenkins, how long did it take to get your Ph.D?
     Jean Jenkins, R.N., Ph.D.: I worked full time at the same time as attending classes part time to get my PhD. So it took me five years altogether. The research portion took the longest (three years) to design my research, implement the study, and analyze the data.
Kelcey Fowler
I am very interested in chimp studies. Is it possible to cross a human and chimp to get a human-chimp hybrid?
     Belen Hurle, Ph.D.: No. Chimps and humans are distinct species. A defining characteristic of a species is that it cannot cross-breed with another. It is called the reproductive barrier. Dogs, no matter how different they may look are all from the same species and can always be crossed. Only in rare cases two different species can be crossed and the hybrid are usually sterile. I can think about lion with tiger (liger) and horse with donkey (mule). Oh wait! you can also cross dogs and wolves, and the offspring is fertile in this case.
Gridiron Footy
Is it possible that if two parents who both don't have sickle cell amenia and have the genotype's "ss" have a child with sickle cell amenia? Thank you and have a nice day.
     Alan Guttmacher, M.D.: Hi, Tyler (wherever in Newton you are -Newton Center, Newton Corner, Newton Highlands, whatever) - It is almost impossible for a child to have sickle cell disease (SCD) unless both parents are carriers for a mutated form of the gene. "Almost" because it is possible to inherit a mutation from one parent and then have a new mutation in the other allele - that is one that showed up only in the specific egg or sperm that led to the child. However, new mutations are quite unusual in SCD, so almost always both parents are carriers of a mutated gene.
Tyler from NEWTON MA
Why did you create this chat room?
     Sarah Harding, M.P.H.: We created this chat room in 2005 so that students across the country could 'chat' with experts in the field of genetics. We wanted to give students a unique look into the field of genetics and careers available. We hope you like it!
diamond from washington, d.c.
Will we ever actually be able to keep the results of genetic tests away from health insurance companies? Potential employers?
     Tim Leshan, M.P.A.: You are right. It will be very difficult to keep all genetic information from insurers or all employers. We would hope is that insurers and employers will establish precautions and guidelines to ensure such information is not misused. Furthermore, in order to protect against the missuse of the results of genetic tests and other personal genetic information, federal legislation is needed
St. Ignatius College Prep High School

Information - Moderator Jean McEwen, a probgram direcdtor in the Ethical, Legal and Social Implications Programs and the International HapMap Project is now in the chat room.

Why is it that humans and chimps are so genetically similar, yet look and behave so different?
     Belen Hurle, Ph.D.: I love this question. I am personally interested in studying the differences between humans and other primates. Some genes have evolved very fast, typically genes that participate in brain functions, sensory perception, metabolism, and reproduction. We are finding more and more examples of such rapidly evolving genes. Sometimes, what changes fast is not the gene per se, but the regulation of the gene (it is expressed with a different timeline, or in a different pattern). These small changes in critical genes have a great impact in the species.
Gridfoot, ph.D.
How many years of college do you have to attend to become a doctor who works in genetics?
     Alan Guttmacher, M.D.: Hi, Savannah - I attended 4 years of college, then 4 years of medical school (after taking off a few years during which I did a bunch of different things - including teach Middle School English and Social Studies), then 4 years of internship and residency in pediatrics, then 2 years of medical genetics fellowship. So, that totals 14 years. However, today that could be compacted into as few as 9 or 10 years, but 12 years would be most typical. Remember, though that those years of training are actually fun, and you get paid for many of them!
Savannah P'Poole Lyon Co. Middle School, Kentucky
What is something you would like to accomplish in your field in the next few years?
     Alan Guttmacher, M.D.: The major thing I would like is to figure out how we use the huge amount of new knowledge in genomics to change the way we practice health care, so that the benefits of genomics actually improve the health of all people.
chelsea/ Westview High School
Are there ways to prevent yourself from getting a genetically inherited disease, like Alzheimers?
     Jean Jenkins, R.N., Ph.D.: Not all persons with Alzheimers (A.) disease have inherited the predisposition for that disease. Those persons who develop symptoms at an early age may be those who have inherited a genetic change that increased their risk for the disease. Not enough is known about all the contributing causes of A. and there is currently no cure. As we learn more about the genetic changes that occur with A. targeted therapies may become more available. For more information about A. visit
Lauren, San Diego
How did you get involved with the Human Genome Project? What was your major in college? Was everyone involved a biology major?
     Alan Guttmacher, M.D.: I got involved by being a physician who was interested in how we might use the knowledge produced by the Human Genome Project to improve human health. My undergrad major was "Social Relations" - essentially, social psychology. The HGP was interesting in that not only biologists played a role, but also computational experts, mathematicians, ethicists, and many others...
Jacob, Sharon PA
What is genetic discrimination?
     Tim Leshan, M.P.A.: Genetic discrimination is the use of genetic information to deny someone a particular benefit. For the most part we think of insurance companies or employers using a genetic test to deny them insurance coverage or a job. NHGRI beleives genetic information should not be used by insurers or employers because it is not fully predictive information. There may be other ways to use genetic information to discriminate against people such as in law inforcement.
How will this genome project help poor people around the world? Is it gonna be the same old thing about the power of money vis-a-vis access to health facilities or is gene therapy going to be cheap enough to be accessible to the poor people (majority) around the world.
     Jean McEwen, J.D., Ph.D.: It is our hope and expectation that the benefits of the Genome Project will eventually reach people all around the world, but realistically, we know that will take longer for these benefits to reach people in resource-poor countries where access to basic health care is limited than to people in more prosperous parts of the world. Gene therapy is actually probably quite a long way off, but long before that becomes available, we expect that information from the Genome Project will lead to improved understanding of many common diseases - including those that disproportionately affect people in developing countries. A good example is malaria. Although malaria is an infectious disease, there are many genetic factors that influence how this disease is transmitted and who is most likely to become sick with it. Understanding these genetic factors will eventually lead to better methods of prevention and treatment for this disease.
Aruna Jalloh
About how many hours do you dedicate yourself to your line of work?
     Alan Guttmacher, M.D.: Great question. It all depends upon the day. I have occasionally spent 24 hours straight working, and some days as little as a few hours. Typically, researchers spend 8 or 10 hours a day working, but one can easily find jobs that require more or less time.
Rebecca Wethington Kentucky

Information - Moderator David Bodine, a physician and an investibgator in the Genetics and Molecular Biology Branch, has joined the chat room.

Information - Moderator Donna Krasnewich, a physician and deputy cloinical director at NHGRI, has joined the chat room.

Would a branch of humans ever evolve backwards, and become primates again?
     David Bodine, M.D., Ph.D.: It is fun to think about questions like this. Probably you know there is no absolutely correct answer. My answer is this. Evolution is a continuous process, it never repeats itself, and the path it will take is determined by random mutations and natural selection for the most beneficial traits. So while there is no doubt that humns will be different from now in a million years, I doubt that we will look like primtes. Likewise over the same time frame, I doubt that primates will look the same, but I do not think they will look like humans. It will depend on the environment andhow we adapt to it.
What inspired you to take your career path as a scientist?
     Alan Guttmacher, M.D.: Most of all, a desire to do work that improved people's lives. Other reasons included the ability to do work that was always challenging and intellectually intersting (I hate being bored), the ability to be the master of my own fate - rather than having others dictate what I do - and the sheer thrill of finding out information from time to time that you are the first one in history to know. The fact that I am well paid, doesn't hurt, either.
Ally from Westview High School...San Diego
How often do patients come in with DNA problems?
     Donna Krasnewich, M.D., Ph.D.: When people suspect that they have problems with their DNA they are thinking that they would have a genetic problem or a problem that has been inherited. The medical staff that see individuals who have genetic problems are called geneticists. Geneticists may be physicians, counsellors or other medical people with expertise in understanding how a change in DNA may affect a person. Sometimes people with genetic disorders look different, or have medical problems that run in their family such as a cancer or hearing loss. Geneticists are trained to take a medical history, family pedigree, examine a person and perhaps even send their DNA for analysis to better understand what is going on.
kelsey martin
Has the chimp genome been sequenced yet?
     David Bodine, M.D., Ph.D.: Yes it has and it is VERY similar to that of humans. In fact the sequence of the DNA that encodes the protein coding sequences are over 99% identical. The current thinking is that if you subsitiuted the chimp proteins for the human ones, you'd get a human. The differences between the species is thought to be related to the things that determine when a protein is made during development.
Pheet Thatare Griddly
Are there certain cancers associated with gene mutations?
     Jean Jenkins, R.N., Ph.D.: ALL Cancers are said to have genetic changes. Some of those changes are inherited, such as 5-10 % of persons with breast/ovarian cancer or colon cancer have a genetic change that can be detected through genetic testing. They may learn that they are at an increased risk for cancer and start earlier screening and prevention measures. Others with cancer may have their cells analyzed to identify their correct diagnosis, best treatment selection, or their risk for relapse. As more is learned about the genetic changes that occur in individuals with cancer versus those who don't have cancer, even greater personalized care will be possible. See http://www.cancer gov to learn more about cancer genetics and the cancer genome anatomy project efforts.
Ryanne, Edna High School
How much government funding is spent on genetic research?
     Alan Guttmacher, M.D.: Good question, but virtually impossible to answer, because many different parts of the federal government are now involved in genetics research. Our part of the National Institutes of Health, the National Human Genome Research Institute, is perhaps the center of the federal government's genetics research, and our budget is just under $500,000,000 this year.
sw, chicago, il
How has your career in genetics played a role in your life?
     Alan Guttmacher, M.D.: Like any career, it has influenced where I live and how much money I make. Unlike some careers, it has made me very happy, given me the opportunity to work with great people, and to do work that benefits other people.
Kelley, Kamiak High School
What's the diffence between Asian people's DNA and white people's DNA?
     Jean McEwen, J.D., Ph.D.: There are no fundamental differences between the DNA of people from different "races." There are only differences in the frequencies of some genetic variants in people whose ancestors came from different geographical parts of the world. So, for example, people whose ancestors came from Asia may have a higher or lower frequency of a genetic variant associated with their responsiveness to a particular drug, or with their susceptibility to a certain disease, such as diabetes, heart disease, or stroke. Knowing about these frequency differences can be very useful for people's health care. However, there is a lot of ambiguity in the way people define their racial identity, which makes attempts to look for essential differences among "races" fraught with problems. For example, people who define themselves as "white" may have ancestry from many different parts of the world other than Europe. And all of us, regardless of the "race" we self-identify with, have ancestry from Africa. So we need to be very careful about making broad-based generalizations about genetically-based racial differences.
Tiffany, Westview Learning Center
Why did it take us so long to discover DNA?
     Jeff Schloss, Ph.D.: Which "discover" do you mean? Regardless of which you mean, it really comes down to technology and being able to "connect the dots." DNA was first isolated in 1869. In those days, people were developing lab techniques they could use to grind up biological samples and purify different kinds of molecules. In parallel, others were studying inheritance. As the ideas spread through the world (don't forget, we didn't have the Internet in those days), some people realized that DNA was the genetic material. That happened in 1944. So it only took 9 years from that discovery to apply the technique called X-ray crystallography to learn the structure of DNA. So the answer is that we need the technology to be available, the ideas to develop and spread, and the right people to get motivated to connect the dots.
Fowlmowth Griddle
What are your thoughts about people giving their DNA to bosses or life insurance questions?
     Tim Leshan, M.P.A.: Most employers will not use genetic infromation, but many people are affraid to give genetic test results to their bosses. There have been anecdotal cases of people providing such information to their employers only to be fired. Emlpoyers may be concerned that a genetic test might mean someone will develop a disease, which will drive up their insurnace costs. When one applies for life insurance he or she can be asked for their medical records. If genetic test information is in your record it could be used by the life insurance company to determine you eligibility or your rates.
Sam, Crawfordsville, Indiana
Dr. Hurle, how did you become interested in science?
     Belen Hurle, Ph.D.: I have had an interest in Biology ever since I can remember, playing with insects, and watching TV documentaries that sort of thing. But my interest in genetics arose when I got to high school and I started learning about DNA and inheritance. I was hooked!
Pheet Thatare Griddley
How do viruses affect the structure of your DNA?
     David Bodine, M.D., Ph.D.: Some viruses can integrate into your DNA and this changes the sequencein that area by adding the virus genes. HIV is an example of this kind of a virus. They introduce a "nick" into the DNA and then use a protein called integrase to insert themselves into the genome. Sometimes they can interrupt a gene, which would cause it to be defective, or it can make a gene that would be silent "turn on" which can cause problems. However, most of the genome does not contain genes so most of the insertions do not cause problems. Other viruses like the ones that cause colds or skin rashes do not integrate into DNA, but they live in cells and make proteins that cause you trouble.
What are the genetic links between Neandertals and Homo Sapiens?
     Belen Hurle, Ph.D.: We actually are two different species of hominids. Neanderthals got extinct and we got going. Some researchers are working hard to extract Neanderthal DNA from fossils, so we can learn more about our similarities and differences at the genetic level.
Roxy St. Ignatius College Prep

Information - Moderator Wow, we're getting a lot of great questions today. Keep on sending them in! Just a reminder to please include the name and the location of your school. Thanks!

What kinds of majors should a college student be looking into if they are interested in archaeology/anthropology but with a concentration in evolutionary genetics?
     Carla Easter, Ph.D.: I would strongly suggest that you major in either anthropolgy or archeology and minor in genetics, molecular biology, or chemistry or take a lot of genetics, molecular biology, and chemistry courses. Of course, it would be best to consult an academic/career advisor to help chart the best academic strategy.
St. Ignatius College Prep
If chimps and humans are genetically related, what about chimps and elephants?
     Belen Hurle, Ph.D.: Chimps and elephants are genetically related too. We are also related at the DNA level with other creatures that don't look anything alike, such as flies and worms. Genes involved in fundamental processes are more conserved (look more alike) and genes that are responsible for species-specific adaptations are more dissimilar between organisms.
Pheet Thatare Griddley
what does DNA stand for?
     Carla Easter, Ph.D.: DNA stands for Deoxyribonucleic Acid. Tough word pronounced easily as "Dee-oxxy-ry-bo-new-clay-ick Acid"
Earl, West Virginia
How are humans and chimps similar genetically? And how does this support the theory that we are closely related?
     Belen Hurle, Ph.D.: At the whole genome level (coding and non-coding sequences), we are 96% identical. If we only look at the sequences that encode genes, we are 99% identical. In practical terms this means that in average for any given gene encoding a given protein, chimps and humans present only 1 amino acid difference and 27% of our genes encode identical proteins. So I would say that we are very similar.
Griddle Foot
To what extent do we know about the complexities of plant genetics? Mendel studied pea plants for simple patterns of inheritance, are plants still helpful studying genetics?
     David Bodine, M.D., Ph.D.: We have lots of information about plant sequence and for exactly the reasons that you described. There are genome sequences for rice, corn and a plant called arabadopsis. The Aradadopsis is a cool plant, it is related to mustard, it grows in small lab dishes and it has a very short life cycle. People are studying a variety of questions about recombination, gene expression and complex inheritance usingthese organisms.
Jane, Chicago
What post-high school education is needed to enter the field of genetics?
     Carla Easter, Ph.D.: There are many routes you can take. Several programs can be found at two-year and four-year institutions that will provide you with a solid foundation in genetics. If you are truly considering doing research, I would recommend a masters or PhD degree in a related field. In addtion, there are many opportunities in genetics for physicians and other occupations, including law enforcement, anthropolgy, engineers, and more.
Anikalia, Mukilteo, Wa

Information - Moderator Joining us now is a special guest from the National Eye Institute, Jennifer Pitrak, post doctoral fellow studying micro-RNA gene regulation.

Do you think it will eventually become acceptable to refuse a mortgage application on the grounds that a person has been found to have a genetic predisposition towards, for example, gastric cancer? If not, what is being done to prevent this?
     Jean McEwen, J.D., Ph.D.: Yes, it is possible that this could happen, and that is why it is important to pass federal genetic non-discrimination legislation that would prohibit such practices. Currently, a number of states have laws that prohibit discriminating against individuals based on their genetic predisposition to particular diseases, but most of these laws focus just on disciminration in employment and insurance; so far eligibility for a mortgage has not been a major focus of concern. A federal genetic non-discrimination law has now been approved by the U.S. Senate, but it is at this time unclear whether it will be passed by the U.S. House of Representatives.
Shivani, Uni of Leicester, UK
Is there any possibility that pre-implantation genetic diagnosis will be used in the future as a way to prevent genetic diseases?
     Donna Krasnewich, M.D., Ph.D.: This is a very sophisticated question. Preimplantation genetic diagnosis is a method where the newly fertilized egg or even the egg or the sperm is analyzed for a specific mutation in a gene that leads to a specific genetic disorder. With this type of information available a couple can make a choice about the pregnancy sometimes even having to choose between an affected zygote (fertilized egg) or an unaffected one. Preimplantation genetic diagnosis is becoming increasingly available for more and more genetic disorders. The availability of this technology comes with very complex ethical decisions that must be made both by the individual and by society. So currently, on a case by case basis, if a couple knows that they are at risk for having a child with a genetic disorder they may be able to choose to have only unaffected children. This technology and the ethical decisions that it requires will continue to evolve.
Aurora P Kamiak High School, Mukilteo, WA
What are the differences between the X and Y chromosome?
     David Bodine, M.D., Ph.D.: They are completely different except for a very small region. The Y chromosome contains the genes that determine whether an embryo will be a male. The X chromosome has genes that are needed for both male and female development. The small egion that is the same is called the "pseudo autosomal" region. This part of thye chromosome behaves like the rest of the chromosomes it that there are two copies of it in every cell. During meiosis it is important for the chromosomes to "cross over". Without the pseudo autosomal region,the male X and y chromosomes could not cross over. Without crossing over, there would be a lot of problems segregatingthe chromosomes, which is why evolution has kept the pseudo autosomal region.
Tyler, Crawfordsville, Indiana
what are chromosomes?
     Carla Easter, Ph.D.: Chromsomes are the carriers of genes and are located in the nucleus of a cell. Different kinds of organisms have different numbers of chromosomes. Humans have 23 pairs.
sophie los angeles
Will public disapproval of animal/human hybridization hinder scientific research? Why is it that this topic has suddenly emerged as part of the bioethical debate? Is this simply a distraction from more serious issues that require more studied evaluation?
     Tim Leshan, M.P.A.: Animal/human hybridization has actually been an issue for some time now. It is a serious ethical issue and we should be careful with any such experiments. But the goal of such work is to better understand human disease so we can develop treatments and cures. So while we should address such ethical concerns we should not slow the progress of science. There aren't any easy answers so we go case by case when these matters come up.
St. Ignatius College Prep High School
Do you think that new findings in genetics require changes to the scentral molecular dogma? Should there be a dogma, since we are still learning new things about DNA, RNA, and proteins?
     David Bodine, M.D., Ph.D.: I think the central dogma: DNA makes RNA makes protein is pretty well supported and is not likely to change. We have certainly discovered exceptions - prion proteins that can act as genetic elements, and RNA viruses that reverse transcribe their genomes to make DNA, but these are rare exceptions and the fundamental obserbations about the relationship of DNA, RNA and proteins will stay the same. If you look at the simplest organisms, viruses and bacteria, you can see the exceptions, but most of the orgnisms follow the dogma.
Irene, St. Ignatius College Prep High School
Is there any current research involving the use of gene therapy to improve athletic performance?
     Donna Krasnewich, M.D., Ph.D.: I do not know of any gene therapy available to improve athletic performance. Since excellant athletic performance is dependent on so many traits including physical features of the musculo-skeletal system, motivation, focus and tenacity one can imagine many genetic possibilities. However, at this time scientists are focusing on human diseases. Play hard and practice strong, don't wait for gene therapy!!
Jordan-Kamiak High School.....Mukilteo
Will you ever, or already have used nano technology to help solve genetic disease?
     Jeff Schloss, Ph.D.: We'll sure use nanotechnology to help make diagnoses of genetic diseases. And scientists are working today on nanotechnology methods for gene therapy, which is one way to treat genetic diseases. There's lots of effort today devoted to nanotechnology solutions to diseases like diabetes, heart disease, and cancer, all of which have a genetic basis. So though nano hasn't been used to cure genetic diseases yet, I'm sure that will occur in the future.
Shahane Newton Mass
How do you realistically explain the evolution of our complex organs like our eyes and our brains?
     Jennifer Pitrak, Ph.D.: That is a great question and one that I ask myself very frequently! I realistically explain it to myself as being a matter of time ... a LOT of time. We, as humans with very short lifespans relative to the time since the inception of life on earth (about 3 billion years ago), have a very difficult time comprehending how long evolution takes. So, lots of time is how I rationalize the complexity of life.
Nate, Sharon
how long did it take to make the map of all the base sequences?
     David Bodine, M.D., Ph.D.: Years. When I was a student 1n 1984, we used to laugh about the foolishness of even talking about sequencing the three billion bases ofthe human genome. There was no map, there was no way to get any sequence except for a very laborious process. However, things happened fast and by 1988, the process began, and the progress was fascinating. The map was a critical first step, and that was done in the late 90's. That way you know which part of the genome you are looking at. The big technology here was the development of the polymerase chain reaction which allowed a rapid way to survey the genome, and the ability to clone large regions of DNA. When the map was done, the DNA sequencing process had been automated to the point that it was possible to do the final sequencing in a matter of months.
student, copiague
Do you think cloning should be legal?
     Tim Leshan, M.P.A.: Human cloning should not be legal. Most scientists and policy makers share this view. There other types of cloning such as DNA cloning which do not involve making a new human being. This type of cloning happens everyday in labs and is crucial to biomedical research.
Pheet Thatare Griddly
Is asthma considered a genetic diease?
     Donna Krasnewich, M.D., Ph.D.: Asthma is considered a multifactorial disorder which means that susceptibility to asthma is probably caused by mutations in several genes along with environmental factors. The genetic basis of asthma has been associated with mutations in the PTGDR gene on chromosome 14q24; ASRT2 , GPRA gene on 7p15-p14; and ASRT3 , which has been mapped to 2p. Polymorphisms in the HNMT gene and the ADRB2 gene have also been associated with susceptibility to asthma. If you Google OMIM which stands for Online Mendelian Inheritance in Man there is a search engine in this fabulous database for what is known about the genetic basis of many disorders.
How would you fit all the genetic info on one microchip, and how would the genetic info be transferred onto the chip itself?
     Jeff Schloss, Ph.D.: Several companies are getting very close to achieving this. They do it by building short fragments of the genome (25 to 90 bases long, depending on the technology) and arraying them across the surface. These microchips are used by scientists all over the world to understand which genes are turned on and off in different diseases, and which genetic changes are associated with those diseases.
Kassandra, Maryland
What do the daily tasks of a geneticist consist of? Do you consider your job(s) stressful? Do you have a boss or deadlines to meet?
     Jennifer Pitrak, Ph.D.: The daily tasks of a geneticist in the early stages of his/her career consist of researching information from the published literature (for example, see PubMed at, setting up and doing experiments in the laboratory, troubleshooting those experiments a lot of the time, and finally, writing up reports and presenations to communicate his/her results to everyone else. Later in a geneticist's career, he/she is less involved in the laboratory and more involved in the other aspects of research.
Ashley W., Kamiak High School
Can your genes change over time?
     David Bodine, M.D., Ph.D.: Depends on what you mean by "yours". If you mean the changes in the cells in your body, there may besome changes, but they will be in only one cell at a time. The proteins that replicate the DNA in cells has a very elaborate proof reading component, so unlike the writer of this answer, virtually all of the mistakes are corrected. Occasionally though you get a change that is not corrected. This can cause cancer, but 99999 times out of 100000 this causes the cells to die. Now, if you mean the genes in you that are passed along to your children and their children, there will be changes that will occur over millions of years. Again most of these will be correected, the rest will be lethal, but maybe one or two in a million years will be beneficial and evolution will keep the change.
Ernie Pyle Middle School, Albuquerque, NM
what is being done to tackle intellectual property issues arising from the human genome project?
     Jean McEwen, J.D., Ph.D.: Many people are interested in this issue and are becoming increasingly concerned that the U.S. Patent and Trademark Office is granting patents for very basic discoveries. This approach potentially impedes downstream research and development to the ultimate detriment of patients and the public. NHGRI has long been committed to the principle of free and open release of genomic data in connection with the large-scale projects it funds. The National Academies of Science recently commissioned a study on the intellectual property aspects of genomics research, and issued a report that includes a number of specific recommendations to ensure that intellectual property laws and policies are applied in a way that preserves the necessary incentives for researchers while at the same time ensuring that downstream developments will not be impeded. NHGRI also funds several investigators who are researching the ethical, legal, and social aspects of intellectual property protections in genomics. The findings from these research studies, along with the findings from the NAS study, will inform the future development of policy in this area.
Shivani, Uni of Leicester, UK
What can scientists genetically modify in babies?
     Donna Krasnewich, M.D., Ph.D.: Scientists are not capable of modifying anything in babies that are already born unless they have a disease that can be changed by gene therapy. As with a previous question about preimplantation analysis, a fertilized egg can be analyzed for whether or not it a genetic trait that is well understood but no change can be made to that fertilized egg. Perhaps someday scientists would like to be able to cure genetic diseases when the fetus is still in the womb. That is still in the distant future.
Emily, John Hanson
What are the benefits of having personalized medicine created through genetics?
     Tim Leshan, M.P.A.: We hope to use genetic information to individualize our health care. Using genetic tests we will be able to determine which treatments one should recieve. For instance a genetic test could be used to determine whether or not someone should get chemotherapy. A genetic test could also be use to determine to dose of a drug. In order to make all this possible we will have to ensure that people feel comfortable obtaining a genetic test and participating in medical research.
mason, maryland
In five years, where do you see the study of genetics going in terms of curing genetic diseases dealing with memory loss?
     David Bodine, M.D., Ph.D.: I think the next 5 years will be very helpful in unraveling these complex diseases. In the last 5 years we have cloned the genes that are involved in Parkinson's Disease, and we have begun to see how the mutant proteins cause the disease. The next 5 years will use the new field of proteomics to understand how these proteins interact. Once that is known, I think it will be possible to design a chemical (there and gazillions of different ways to combine atoms, much more diversity tht you can get with 4 bases and 20 amino acids) that will prevent the harmful interaction whileallowing the beneficial ones. Five years might be soon, but I doubt it will be too much longer than that.
Jenn H, Kamiak High School, Mukilteo, WA
What is the difference between RNA and DNA?
     Jennifer Pitrak, Ph.D.: That is a very good question. One difference between RNA and DNA is the type of sugar in the molecule. "RNA" stands for ribonucleic acid and consists of the sugar ribose and nucleic acids. "DNA" stands for dioxyribonucleic acid and consists of deoxyribose and nucleic acids - the same nucleic acids as there are in RNA. Also, RNA and DNA serve different functions in the cell. DNA contains information for the entire organism's structure and function. All DNA is present in every cell of the body (expect in red blood cells and in mature lens cells). RNA, on the other hand, is generally a "copy" of a portion of the DNA and directs the synthesis of proteins and/or regulates the expression of other portions of DNA (called "genes").
Allana, John Hanson Middle School
Will there ever be a stop to all genetic diseases?
     Donna Krasnewich, M.D., Ph.D.: You know that we all carry changes/mutations in 7-10 genes just as part of our evolution. Evolution continues...... deleterious mutations will continue to happen as long as humans continue to reproduce. I don't see an end to genetic diseases. Hopefully, you will all study hard so that you can someday solve as many genetic questions as you can. Who knows what will happen 100 years from now???
alexa, waldorf
What research is being done to prevent cancer?
     Jennifer Pitrak, Ph.D.: A LOT of research is being done to prevent or cure cancer. One way you can get a good idea of how much research is being done on cancer would be to do a search for it on the PubMed website ( This is a database of all scientific data (not just cancer research). You will likely see thousands of results. Try it!
Kaits, MA, USA
What is the biggest difference between your DNA and your parents' DNA?
     David Bodine, M.D., Ph.D.: Not much. You get half your DNA from each of your parents. The only difference would be mutations that occur early after fertilization. You are a little bit more like your mother because you inherit ALL your mitochondrial DNA from your mother (it is in the egg), and none from your father (sperm have no mitochondria). However, mitochondrial DNA is a tiny percent of all your DNA.
What is the effect of infecting someone with a virus that is meant for gene therapy?
     Donna Krasnewich, M.D., Ph.D.: Actually in gene therapy scientists are not infecting someone with a virus they are using the genes that help the virus insert into DNA to help helpful genes get inserted into DNA. The harmful genes of the virus are not given to individuals in gene therapy. Some of the problems that scientists are having with gene therapy are that it is hard to get the corrected genes into the cells that need them and sometimes the genes insert into the wrong spot which can cause problems.
Ronald, Albuquerque Academy

Information - Moderator Don Hadley, an investigator in the Social and Behavioral Research Branch, is now in the chat room.

How is DNA identified, used, and tested in the field of forensics?
     Jennifer Pitrak, Ph.D.: That is a good question. I am not a forensic scientist. But, from what I do know about genetics, the uniqueness of each person's DNA is used to identify people (ie. crime suspects). This uniqueness is especially found in certain regions of the human genome (all the DNA/genes in a human) and those regions are examined more closely by standard molecular techniques to evaluate whether two DNA samples are the same (from the same person) or different (from different people).
Setha, Groton

Information - Moderator Dale Lea, a nurse and health educator in the Education and Community Involvement Branch at NHGRI, is back in the chat room.

Do you think we should label genetically modified foods?
     David Bodine, M.D., Ph.D.: Yes. I think the more people know about what they eat, the better. I am in favor of genetically modified food. The rice with additional nutrients could allow us to give more and better nutrition to the many starving people who desperately need it. Disease resistent plants would reduce the environmental problems of pesticides and would allow farmers to make more crops and feed more people. At the same time I think we need to make sure that these modification are fully and carefully tested before we use them. I rely on the FDA for that, and I think they are being very complete and careful.
Has there been any more headway in an anti-genetic discrimination law? I heard Dr. Collins discussing such a law at a biotech symposium recently, but he said that it stalled in the House of Representatives.
     Tim Leshan, M.P.A.: The pending anti-genetic discrimination bill H.R. 1227 is still pending in three committees in the U.S. House (it passed unanimously in the Senate). The bill has 182 co-sponsors. Dr. Collins is hoping that the three committees will take up this bill this year and it will go to the floor for a vote.
Luke Taylor, Virginia
If you have sickle-cell anemia - the trait - and you get married to someone who doesn't, will your child have the trait?
     Dale Lea, R.N., M.P.H., C.G.C: If you have sickle cell trait, that means that you have one copy of the gene change that causes sickle cell on one of one of your number 11 chromosomes. The other chromosome number 11 carries an unaltered gene. Each of your children, then, has a 1 in 2 (50%) chance to inherit the sickle cell trait from you.
ceci and im from los angeles
To the director of Ethical, Legal and Social Implication programs, what is the most interesting part of your job and the most fasinating discovery you have come about?
     Jean McEwen, J.D., Ph.D.: I especially enjoy working directly on some of the major reseach projects NHGRI supports (like the HapMap Project and medical sequencing projects) to provide guidance about how to conduct the research in an ethical manner. This can sometimes be really challenging, but it is exciting because so much of the work at NHGRI is at the cutting edge of science, so the ethical issues that are raised are really novel and challenging. The most interesting discovery is how quickly the field moves, and how the answers we thought we were sure about a year ago may no longer seem so clear a year later. This is true for both the basic science and the ethical, legal, and social issues.
Megan Longhorn, Kamiak High School, Mukilteo, Wa

Information - Moderator Nathaniel "Nate" Sutter, a post doctoral fellow in the Cancer Genetics Branch in NHGRI, is now in the chat room.

On my dad's side of the family, no one has lived past 55 yrs. of age, because of diabetes. Can I get it too because I am overweight also? Is being overweight genetic?
     Donna Krasnewich, M.D., Ph.D.: This is a very important question and I am glad you asked. The very best thing you can do right now is to make sure that you are seeing a doctor who you can talk to and who understands your family history. Because diabetes is a multifactorial disorder, which means that many genes may play a role, your risk may be difficult to exactly identify. However, there is lots of evidence that being overweight increases risk of diabetes. On the other hand, if diabetes is identified early and kept under control people can do very well. Take care of yourself, I know this is difficult but please know that there are lots of people out there to help. Good luck!!
Fei from Delaware
Is it or will it ever be possible to go in and have your genes changed to get a certain trait and also pass it down to future children?
     Don Hadley, M.S., C.G.C.: It is hard to know if the techonology will ever go that far, but maybe the more important question is whether it should go that far. Our interest in understanding our genetic make-up is not to create "designer" children, but rather to understand enough about our genetic make-up to reduce our chances or prevent us from developing disease. Instead of "replacing" genes, it is more likely that certain drugs could be developed that would influence our risks for disease rather than replacing genes. Hope this helps.
Alyssa from Westview High
What type of disease is carried on the Y chromosome?
     David Bodine, M.D., Ph.D.: Depends on whether you consider certain male behaviors like shopping aversion and refusing to ask for directions a disease. If you don't, there should not be any deleterious genes on the Y chromosome. The Y chromosome has no partner, so any deleterious mutation would not have a normal gene on another chromosome to make the normal gene product. Any disease mutation on the Y chromosome would be lethal and the male with that mutation could not pass it along to any offspring.
Why shouldn't you take a genetic test?
     Tim Leshan, M.P.A.: You might not want to take a genetic test if you are concerned that such information could be used against you. Some people have paid for such tests with cash so that it doesn't go into their medical record. We hope that people will feel entirely comfortable getting a genetic test in the future, but without comprehensive genetic non-discrimination legislation we can't assure that such information won't be used against you by an insurer or an employer. For more information check out Barb Biesecker's web cast at
Allana, John Hanson Middle School
Why would someone want a genetic test?
     Dale Lea, R.N., M.P.H., C.G.C: There are a lot of different reasons for choosing a genetic test. There are prenatal tests, diagnostic genetic tests, presymptomatic (before you have symptoms) genetic tests, predisposition genetic tests (you have a higher risk to get the disease), and pharmacogenetic tests (help to choose the right drug at the right dose). A person might choose to have a prenatal genetic test to find out more about the health of their baby, if they want to know. Diagnostic genetic tests can help a person know what genetic condition they have and how they got it. Knowing the diagnosis can help with treatment. Some people choose presymptomatic genetic testing because they want to make plans for their life and lifestyle. Individuals choosing predisposition genetic testing, say for breast cancer, may choose this testing so that if they carry a gene mutation, they can make decisions about enhanced screening and treatment. Pharmacogenetic testing can help with better and more accurate treatments.
Loosels from Mukilteo Washington
how many types of RNA are there?
     David Bodine, M.D., Ph.D.: Lots. But the major ones in mammalian cells are (in order of abundance) transfer and small nuclear RNAs, ribosomal RNA and finally messenger RNA, which accounts for less that 1% of the RNA in any cell. Some viruses have an RNA genome. Every gene has a unique messenger RNA, so if you mean how many individual RNAs are there, it is probably over 100,000 for mammals.
Francisco, California
What is your job and do you like it?
     Don Hadley, M.S., C.G.C.: I am a genetic counselor. I work with families that have either an inherited disease or have a family member that has a genetic condition. We help them know more about the condition, what to expect as far as what might be related to the condition in the future, if there are treatments available and whether it can happen to other family members. I've been doing this for 25 years and I can't imagine a more rewarding job. I love it!
Brennon T. Chen Los Angeles, Palms middle school
Do you think that the atheleticness is a gene that funs in a family?
     Jennifer Pitrak, Ph.D.: That's a good question. A lot of physical and emotional attributes are influenced by genes. However, environment (ie, nutrition, exercise, health, etc.) also contributes to one's attributes. Both nature (genes) AND nurture (environment) influence people's personal characteristics.
Nick Talmo Delaware
When gene therapy is able to be used on humans do you think that people will take advantage and use it to create super humans or the perfect child?
     Jean McEwen, J.D., Ph.D.: Effective gene therapies for diseases are probably quite a ways into the future, and the prospect of gene "therapies" for the enhancement of normal human traits is even more futuristic. Nevertheless, it is a good idea to start thinking about this possibility now, so that eventually, if enhancement therapy does become technically feasible, we are prepared to address the consequences. Addressing this question requires us to think about how we define "health" and "disease," what it means to be "normal," and how we determine what traits are/are not "desirable." Currently, the Ethical, Legal, and Social Implications Program at NHGRI is funding researchers who are studying these questions, in anticipation of the possibility that we as a society will someday need to directly confront these issues (since if the technology eventually exists, there will undoubtedly be parents who will want to use it).
Alena L.,Mukilteo,WA
what is chromosome?
     Nate Sutter, Ph.D.: The genes we carry in the nucleus of the cell exist on chromosomes. Each chromosome is an extremely long molecule the cell uses to store information. The information is transmitted as the 'A', 'C', 'G', and 'T' nucleotides you've probably heard about. The cell has careful and complicated processes to make a copy of each chromosome during cell division and to make transcripts of each gene in the appropriate cell types and under the appropriate conditions.
nat e.
What causes William's Syndrome?
     Donna Krasnewich, M.D., Ph.D.: This answer is edited from a very nice review about Williams Syndrome by Dr. Colleen Morris from GeneTests at www.genetests,org : Williams syndrome (WS) is characterized by cardiovascular disease (elastin arteriopathy, peripheral pulmonary stenosis, supravalvular aortic stenosis, hypertension), distinctive facies, connective tissue abnormalities, mental retardation (usually mild), a specific cognitive profile, unique personality characteristics, growth abnormalities, and endocrine abnormalities (hypercalcemia, hypercalciuria, hypothyroidism, and early puberty). Feeding difficulties often lead to failure to thrive in infancy. Hypotonia and hyperextensible joints can result in delayed attainment of motor milestones. The diagnosis is made by detection of a contiguous gene deletion of the Williams-Beuren syndrome critical region (WBSCR) that encompasses the elastin (ELN) gene. Over 99% of individuals with the clinical diagnosis of WS have this contiguous gene deletion, which can be detected using fluorescent in situ hybridization (FISH) or targeted mutation analysis.
Esteban, Spain

Information - Moderator Colleen McBride, the chief of the NHGRI Social and Behavioral Research Branch, is now in the chat room.

If my whole family is short does this mean that I will also be short?
     Jennifer Pitrak, Ph.D.: Physical attributes result from genes and environment. So, there may be genes within your family that lead to "shortness" rather than "tallness" and you may have inherited these genes. Either way, you are a unique person with a lot of great characteristics.
Could Tay-Sachs disease be treated by gene therpy to a fetus still in the womb?
     Dale Lea, R.N., M.P.H., C.G.C: Gene therapy to treat a fetus with Tay-Sachs disease while the fetus is still in the womb is not done at present. There is some work being done with stem cell therapy to treat children who have Tay-Sachs disease.
Kiara Sledge, Birmingham,AL
Would it really be possible for humans to one day live 4 times the average lifespan, from what was discovered with nematoads?
     David Bodine, M.D., Ph.D.: I doubt it. Although some cells can be replenished from stem cells, it looks like in mammals, even the stem cells wind down eventually. For example, you see a lot more cancer etc. in older people. It seems like it is only a matter of time before you acquire problems. Your blood forming stem cells can survive for several generations, but your other cells wear out first. In worms the cell growth is determined by apoptosis a process where certain cells ae positively signalled to die. If you lock the death signal, they live until the cells wear out. Mammals have more death pathyway signals to block in many more organs, so i eally do not see it happening.
Jememi III from MA
What is the process between when the point that a new genetic disease is found, and when a cure is developed?
     Don Hadley, M.S., C.G.C.: THere is usually a long time between when a disease is recognized, a genetic cause is discovered and treatment is developed. In fact, there are only a few genetic diseases that can truly be prevented. The diseases that are checked for at birth (newborn screening) are some great examples; phenylketonuria (PKU) for example. But many others such as some of those that occur in adulthood ( cancer, alzheimer disease) etc. do not have a "cure" just yet. A lot of research is still needed before we can truly prevent these diseases from occurring. We could use your help. Come join our team when you get through with your schooling.
Guy Black Carver High School Houton
Can the genome sequence be a boon for burn cases?
     Dale Lea, R.N., M.P.H., C.G.C: There may be some genes that support skin growth and recovery or perhaps the genome sequence will uncover growth factors that may enhance the recovery of burn patients. So there is hope!
Sainani INDIA
Is there a gene for criminal behavior and if so how is it identified?
     Colleen McBride, Ph.D.: As of now, there is no gene that has been uncovered for criminal behavior. Indeed it is unlikely that we will ever discover a single gene that can determine such a complicated behavior. As you probably know criminal behavior like many other behaviors is socially influenced. What is considered to be "criminal" in one society is not in another. What we think now is that there may be many genes related to personality that each may play a very small role with a bigger role played by social influences that affect whether someone engages in criminal behavior.
newton, montana
I have down syndrome, but nobody in my family does. Is down syndrome something carried by genes?
     Donna Krasnewich, M.D., Ph.D.: I am glad you asked this question. People with Down Syndrome typically have an extra copy of chromosome 21 in some or all of their cells. So it is carried in your genes. But it is usually not something that is passed down from the parents. Thanks for interacting with this Chat Room, I love hearing from you.
Pat Callaway, Delaware
Why are we celebrating DNA day today? Not on Feb. 28, the day that it was discovered?
     Sarah Harding, M.P.H.: That's a great question! DNA Day is celebrated on April 25 as a celebration of the completion of the Human Genome Project. April 25 was the date of the publication of the sequence.
Leslie A from Mukilteo, WA
are all diseases passed on through genetics or is it just certain ones
     Belen Hurle, Ph.D.: There is a genetic component almost in every disease, with the exception of perhaps trauma. Sometimes a disease has a 100% genetic origen, sometimes your genetic background is more of a increased risk factor to develop a disease. On the other hand, not everything is caused by problems with genes. The environment and your life style choices (exercise, diet, smoking, alcohol) have also an impact in determining if you ever develop a disease or you don't.
Timmy Westview
My mom is a high school English teacher and she has a set of what she thinks is identical twins. But one has a mole and the other doesn't. She wants to know if the mole is genetic or if they aren't really identcal twins.
     Dale Lea, R.N., M.P.H., C.G.C: Even though identical twins share the same genes, they often look slightly different because of environmental factors. So, just because they are identical does not mean that they will look the same in all ways.
Sarah T.; Los Angeles, California
If I were married and was about to have a child. Since my husband has blue eyes , and i have brown eyes what is the chance that my child will have blue eyes?
     Jennifer Pitrak, Ph.D.: I believe that eye color is influenced by more than one gene, which would make the answer to your question more complicated. But, if we assume that only one gene (two alleles per gene) is involved and that the alleles of that gene can be either "blue" or "brown" and that "brown" is dominant to "blue" (meaning that if one copy of "brown" is present then eyes will be brown), then whether or not your child has blue eyes will depend on whether or not you have one or two copies of the "brown" allele. If you have two copies, your child will have brown eyes. If you have one copy of "brown" (then you also have a copy of "blue") then your child will have a 50% chance of having brown eyes.
Amani Nathaniel, California
Can you have DNA that is weaker or stronger than other DNA in your body?
     Nate Sutter, Ph.D.: Thanks for the question! We have to think about what we might mean by "weaker" or "stronger"... certainly it's true that some DNA more strongly determines our health, appearance, and so on, compared to other stretches of DNA. For every million bases of DNA, only a few percent actually code for RNA or protein molecules. In addition, some other DNA sequences help determine whether a gene will be expressed or not. The most exciting answer to your question, to me, is that we are still actively researching what DNA sequences do. There is much we have left to learn. Maybe you will help us!
Mike, Groton Academy
What would be the effect of a human having an extra pair of chromosomes?
     David Bodine, M.D., Ph.D.: Usually it is lethal. When a sperm or an egg delivers even one extra chromosome, the effects are usualy lethal early in development. The uterus is a very smart organ. It detects when things are not going right and stops it from developing. The only trisomy (3 copies of one chromosome) that even occasionally can survive to birth is chromosome 21 (Down Syndrome). You rarely can see individuals with multiple X chromosomes. This is because all but one X chomosome will be inactivated just like 1 X chromosome is inactivated in normal females. However, even with the X inactivation, these individuals have problems with growth and mental development. I have seen pictures of cells from people with 8 X chromosomes, but the effects are not good.
Demetrius Bettis Birmingham Alabama
Are there laws about if insurance companies can reject people with diseases,etc after taking genetic tests?
     Tim Leshan, M.P.A.: Depending whcih state you are in, it is legal for insurance companies to use information both about a person's diseases and their genetic tests to set premium rates. While it is understandable that insurers would use information about someone disease status to determine eligability or one's rates, the NHGRI believes that genetic information should not be used in such a context. While genetic tests can determine one's relative risk for some diseases, they don't usually predict whether or not one will get a disease. Therefore, using genetic information to determine insurance eligability would be over valuing such information and therefore would be unfair.
Casey, Maryland
What are some risks of having your genes genetically modified?
     Donna Krasnewich, M.D., Ph.D.: We know that our genes operate in an incredible network, acting alone and interacting with a few or many other genes. When gene therapy puts a gene into a cell it is targeted at a specific cell that will use the gene to produce a specific protein. Unfortunately sometime the gene inserts in a dangerous spot that cause other clinical problems. Scientists continue to work very hard to make gene therapy safe and useful.
Emily, John Hanson Middle School, MD
Does Dna affect how a person is immune to a disease?
     Dale Lea, R.N., M.P.H., C.G.C: Yes, a person's DNA can affect his or her immunity to a disease. There are some instances of rare, inherited immune deficiencies severe combined immunodeficiency (SCID). But everyone's immune system is influenced by their genetic makeup. Much more work needs to be done to further understand the genetic contribution.

Information - Moderator Two of our experts who were in the chat room earlier today are back again for more: Belen Hurle, Ph.D., a research fellow in the Genome Technology Branch, and a science educator in the Education and Community Involvement Branch, and Carla Easter, Ph.D., an science education specialist in the Education and Community Involvement Branch.

Is there a chat room that is always up? Or is this only the one day of the year to talk to someone?
     Sarah Harding, M.P.H.: This DNA Day chatroom is held once a year, just on DNA Day. But we try to be available all year to answer questions students might have, or keep online information available for alternative resources.
Billy Kentucky
how much dna is in one human body?
     Jennifer Pitrak, Ph.D.: That's a great question to which I do not have a specific answer. BUT, I do know that the DNA in ONE cell, if stretched out, would be 2 meters in length! There are billions of cells in the human body. I believe that if you stretched out all the DNA in one human body and lined it up end-to-end it would go all the way to the moon and back to earth!! I hope this gives you a feel for how much dna is in one human body.
jimmy sprinkle, sprinkletown usa
Is there any method to cure shingles using gene therapy?
     Dale Lea, R.N., M.P.H., C.G.C: Not that we are aware of.
Sainani INDIA
Can we detect mutations before the disease occurs?
     Don Hadley, M.S., C.G.C.: In some situations, we can detect mutations before the disease occurs. For example, some families have inherited diseases that show up when they are adults. If a mutation has been identifed in that family, then genetic testing could be done for people in that family to know whether they have the mutation and would be more likely to develop the disease. Some examples are the inherited forms of cancer or neurological diseases like Alzheimer disease or Huntington Disease.
Sainani INDIA
is it possible to swap DNA of a human and animal so that the human would take on the animal traits and the other way around?
     Belen Hurle, Ph.D.: Yes, it is possible to transfer genes between organisms. It is called recombinant DNA technology or genetic engeeniering. However, no one engineers humans to express genes from other organisms, it is more the other way around. For instance, you can genetically modify bacteria in a way that they produce a protein with a medical interest, such as human insulin or human clotting factor. Or you can introduce a gene in a crop that make plants resistent to insects or sub-freezing temperatures.
Nicole, Westview High School
what is a genotype?
     Jennifer Pitrak, Ph.D.: A genotype is an individual's genetic make-up. It consists of a person's (or any organism's) DNA.
I'm currently a junior in college and I am interested in doing genetics research with a focus on cancer research. What are some good programs to look at for it and to get your Ph. D do you have to get your master's degree first?
     Carla Easter, Ph.D.: There are several good programs around the country. The US News and World Report ranks graduate programs each year and you can look on the web and in a bookstore for other types of books that rank the programs. Be sure to look at characteristics of the programs that are important to you. For example, time to completion of degree, number of students that complete the degree, where the graduates go after completing their degree, etc. Also, look at schools that are doing the kind of research you would be interested in. Some programs require you get a masters first and then a PhD. There are also programs that accept applicants directly into the PhD programs and do not require that you have a masters. It just depends on the type of program and institiution.
Ashley, Greensboro, North Carolina
Is athletic ability inherited?
     David Bodine, M.D., Ph.D.: To some extent. Height and fast twitch muscle mass have strong genetic components. But I think environment has at least as much to do with athletic performance. How many times have you seen somebody who is not the fastest runner or the best athlete succeed in sports? A lot. They work harder than people with more natural ability. Have you every heard of a superb athlete who does not practice and "wastes" his ability? There ae lots of them.
The chance of fraternal twins sharing the same genes is the same as regular siblings. Then how come I often see fraternal twins who often look so similar?
     Dale Lea, R.N., M.P.H., C.G.C: Just remember that you also see brothers and sisters who look very similar. Brothers and sisters who have the same parents can share similar characteristics.
Lindsey, Mukilteo, WA
Is having a genetic test expensive?
     Tim Leshan, M.P.A.: It depends. Some tests are thousands of dollars while others are just a few dollars. Many tests are covered by inurance, but if you don't have coverage it can be quite expensive.
Erin from Westview Highschool
Isn't today also the day that the double helix was discovered?
     Geoff Spencer: Today, April 25, is the day that Watson and Crick published the description of the structure of DNA's double helix. You might want to read Watson's personal account called "The Double Helix." They actually discovered it in February and announced it in the local pub.
Do you think parents should be able to chose their child's genetic traits?
     Colleen McBride, Ph.D.: This is a very complicated issue that is being debated by a lot of groups. What surveys tells us is that most Americans feel comfortable with genetics being used to prevent children from having health problems. I would count myself in that camp. However, what Americans are less comfortable with is using genetics to select other traits such as gender, athleticism and other characteristics that are perceived to be more desirable socially. All of these issues will continue to be debated and considered carefully as we develop public policies for using new genetic technologies.
Meosha, JhonHanson
How do introns get spliced out from mRNA? How does the body detect whether a segment of mRNA is an intron or exon?
     Jennifer Pitrak, Ph.D.: This is a great question! Introns get spliced out of pre-mRNAs by enyzmes in the cell nucleus. Introns are recognized by these enzymes because of specific sequences in the mRNA that delineate the intron (intron-specific sequences).
D. Lawrence, New York
Do you see many patients with Fragile X syndrome?
     Donna Krasnewich, M.D., Ph.D.: We do not see many people with Fragile X syndrome at the National Institutes of Health but geneticists at many universities and hospitals see many cases of Fragile X syndrome. The frequency of Fragile X is about 25:100,000 males.
Alyssa, California
Can your genes change over time?
     Nate Sutter, Ph.D.: Yes! There are a number of ways this is true. First, genes can change any time they are copied. When a cell divides in two, the DNA must be copied (carefully) by enormously complicated enzyme "machines" in the nucleus. Very rarely, these machines make mistakes. When that happens, a DNA change may be introduced into a gene. This happens when we inherit chromosomes from our mother and father and it also happens when we develop from a single cell (the fertilized egg) into a baby and then adult with trillions of cells. The genes in our brain cells differ from the genes in our stomach lining or kidney. This process (called cellular differentiation) enables our cells to specialize in particular tasks. Each task requires a different set of gene "tools".
Lymiracle Hill, Hogdson Vo-Tech
Is their any way that cystic fibrosis can be cured?
     Dale Lea, R.N., M.P.H., C.G.C: Researchers are working on many different strategies to improve the health of individuals with cystic fibrosis. These include traditional medicines and drugs as well as gene therapy approaches targeted at decreasing mucous formation in lungs and/or improving lung functions in individuals with cystic fibrosis. Unfortunately, we still don't have a way to cure cystic fibrosis at this time.
Ulises Garfield NJ
If I am interested in studying Genetics for a career, how should I prepare myself?
     Sarah Harding, M.P.H.: There are many ways to get into a career that involves genetics. An important thing to do right now is to take classes involving biology and genetics, to build up your base level of knowledge in the topics. Take a look at the many different types of careers in genetics to get an idea of what will be required to get involved. The most important thing is to pick something you are interested in.
Matthew G, Hazel Park High School, Michigan
How do you determine whether or not to tell a patient that they have a genetic disease?
     Don Hadley, M.S., C.G.C.: If a person or family comes to us asking questions about whether a condition in them (or their family) is inherited, then we tell them what knowledge is available. We do not withhold information, but we do help them adjust to the news and develop plans as to how they can move forward and use the information in a helpful way. There are some family members in families with inherited diseases that do not want to know about it. This can make it hard within the family since some want to know and others do not. We worry that this situation may make some family relationships difficult.
Kayla, Mukilteo, Kamiak High School
Can't we think of making this Day as International DNA Day
     Sarah Harding, M.P.H.: We are certainly happy to have so many of you from different countries logging in with such great questions!
B.B.S.P.Nag, SMV Centre for Biotech, Nagpur, India
Can you manually change a letter in the DNA sequence and not just at random like radiation does?
     Belen Hurle, Ph.D.: Yes you can do it! It is called targeted mutagenesis. It is a very useful technique to recreate a specific human mutation in a model organism, such as mouse or zebrafish, that can in turn be studied in the laboratory.
Caecilius Pompeii
Is diabetes a genetic disease?
     Donna Krasnewich, M.D., Ph.D.: Diabetes is considered a multifactorial disorder. This means that susceptibility to diabetes may be caused by the interaction of many genes including genes on chromosomes Gene map locus Xp11.23-q13.3, 12q24.2, 12q24.2, 1p13, 6p21.3. Environmental factors also probably play a role. This is a very complicated story and there is alot of work being done in this field.
Fei from Delaware
How do drugs cause genetic mutations? do they stop ligase from working? or is it some other mechanical disfunction that changes the DNA code?
     Nate Sutter, Ph.D.: Great question! Certain chemicals and high energy particles cause physical damage to the DNA molecule. A damaged molecule can't properly be copied during cell division so the cell makes every effort to repair the damage. If the damage is missed during cell division or the damage is repaired improperly, a change in the DNA sequence (mutation) may result.
Lappi, Clarkstown North, US
What does it mean to mutate? What exactly in the DNA gets changed or altered that causes disorders?
     Carla Easter, Ph.D.: To mutate means to change. There are several types of mutations that can occur in the DNA. There are single base pair changes. For example, an A can get changed to a C, a G to a T, etc. You can also have deletions of bases or insertions of bases. Some mutations do not cause any changes in the protein sequence and others can cause changes that lead to genetic disorders.
Amir, Westview High
Hello! I am interested in pursuing a career in genetics. What should I major in in college?
     Sarah Harding, M.P.H.: There are actually multiple college majors that can lead to careers in genetics. In fact, one does not necessarily need to major in a science degree to pursue a career. As long as you take the right courses to pursue graduate school or medical school, you can major in any topic of interest to you. If you aren't interested in pursuing graduate school, then it is probably a good idea to major in biology or chemistry, or something related to the two.
Pheet Thatare Griddley, Chile
Have they used gene therapy for sickle cell disease?
     Don Hadley, M.S., C.G.C.: Researhers are still working on using genetic technologies to prevent some of the problems caused by Sickle Cell Disease. Right now most approaches to treating Sickle Cell have been by utilizing specific medications to prevent or treat the problems that go along with it. There will other therapies that arise as we learn more. Stay tuned. Even better - study hard and come join our team to find ways to use genetic knowledge to prevent and treat disease.
jessica, john hanson
Is there any way to cure a genetic disorder?
     Dale Lea, R.N., M.P.H., C.G.C: Scientists are working on techniques to treat genetic disorders, but to cure a genetic disorder would mean that you would have to change the DNA in every cell of the body. This is not currently done.
How can I get others involved and more aware of DNA day?
     Sarah Harding, M.P.H.: That's a fabulous question. There are multiple ways to get involved in DNA Day. A few of our suggestions are to certainly watch the webcasts and participate in the chatroom. But you can also help to connect genetics researchers and other professionals to science classrooms in your area to help get students excited about genetics.
Pheet Thatare Griddley
Will genetics affect our diets in the future?
     Donna Krasnewich, M.D., Ph.D.: Genetics may help us to grow fruit and vegetables more efficiently or raise livestock more effectively, that may change our diets. There is research being done on how individuals use food for energy, for example, this field is called nutrigenomics.
Billy, Morrisonville, IL
How do our behavior and social skills relate to our DNA?
     Colleen McBride, Ph.D.: This is the million dollar question that many researchers will spend their entire careers trying to answer. What is clear from the research thus far is that how we behave is likely influenced by a combination of genetics, social and environmental factors. These factors are numerous and work together in complicated ways to make us who we are. Because there are so many genes and so many possible social influences that affect personality alone, their relative contributions to behavior and social skills will be hard to specify.
Lauren McCulley
Este descubrimiento affecta solo a los Americanos de Estados Unidos o es para el mundo entero
     Belen Hurle, Ph.D.: Hola! los avances en genetica no tienen pais, son patrimonio de la humanidad. Una de las condiciones del projecto genoma humano fue que todos los datos generados serian puestos a la disposicion de todos los cientificos del mundo imediatamente a traves de la web, sin patentes. Cualquier persona con un computador en cualquier parte del mundo puede estudiar el genoma humano. Lo que si es cierto es que las aplicaciones medicas frecuentemente se originan en USA y Europa y luego se extienden a otros paises.
Massiel Parra Garfield High School , NJ
Do you use punnet squares to see what the percentage of the something will be on the child?
     Don Hadley, M.S., C.G.C.: Punnet squares are a very important and simple tool that we have all used when we first got started in genetics. As one gains experience, they no longer need to actually draw out the square, but can determine risks based upon what is known about the inheritance of the condition in question. Is it autosomal dominant or recessive, x-linked or mitochondria? The answers to these help in detemining risks to our children. Keep practicing those squares and learn as much as you can about genetics!
Is scoliosis a genetic disorder?
     Donna Krasnewich, M.D., Ph.D.: Scoliosis, which is curvature of the spine, appears to be caused by changes in one or more of several genes, this is called a multifactorial disorder. Scoliosis may also be part of a syndrome which is a collection of clinical features that are associated together in a person. There is currently research going on the genetics of scoliosis at the NIH.
Ashley Greensboro, NC
Exactly how easy is it to change an organism drastically with only one small part of a DNA?
     Belen Hurle, Ph.D.: Very easy. The most drastic genetic disorders in humans often come from a change in only ONE letter of the human genome. Or you can easily make a bacteria produce a human protein by inserting the corresponding human gene in the bacterial genome.
Lindsey Marie, john hanson,MD
Can you find Dna in any cell?
     Belen Hurle, Ph.D.: Almost. Red blood cells and eye lens cells don't have DNA!
Emanuel, From Los Angles
I would like to say big hello from Japan (It is 3AM here) ? It is exciting to think that DNA science is really universal all over the world. Are there any similar activities like the American National DNA day in other countries?
     Sarah Harding, M.P.H.: Hello to Japan and welcome to the DNA Day chatroom! We are thrilled that so many people from different countries have logged into the chatroom with questions. DNA Day began in April 2003 with the completion of the Human Genome Project, and we would hope that as DNA Day gains awareness and popularity, there will be activities held all over the world. We encourage you to host activities for DNA Day in your country next year!
Chieko Tamura, Tokyo, Japan
if addiction runs high in my family what will the chances be that i will have an addiction to drugs or alcholol?
     Dale Lea, R.N., M.P.H., C.G.C: Right now we have no way of predicting whether somebody is going to be addicted to alcohol or drugs. Genetics is just one component of who we are. We are a combination of our genetic makeup, environment, and family history.
nicole, fredericton
What is Tay-Sachs disease?
     Carla Easter, Ph.D.: Tay-Sachs disease is a fatal genetic disorder. The condition is caused by insufficient activity of an enzyme called beta-hexosaminidase A that breaks down acidic fatty materials known as gangliosides. Gangliosides are made and broken down rapidly during early brain development. Infants with Tay-Sachs disease appear to develop normally for the first few months of life, but then deteriorate mentally and physically. A much rarer form of the disorder occurs in patients in their twenties and early thirties and is characterized by unsteady movements and progressive neurological deterioration. The incidence of Tay-Sachs is particularly high among people of Eastern European and Askhenazi Jewish descent. Patients and carriers of Tay-Sachs disease can be identified by a simple blood test that measures beta-hexosaminidase A activity. Both parents must carry the mutated gene in order to have an affected child. In these instances, there is a 25 percent chance with each pregnancy that the child will be affected with Tay-Sachs disease. Prenatal diagnosis is available if desired. Presently there is no treatment for Tay-Sachs disease. For more information visit the Tay Sachs information page at the National Institute Neurological Disorders and Stroke web site:
Massiel Parra Garfield High, NJ
Do you think genetics will ever get to the point where humans will be able to create "perfect people" or design children with specific physical characteristics?
     Colleen McBride, Ph.D.: It is already possible to use genetics to influence specific physical characteristics such as gender. Creating "perfect people" is an interesting notion since what defines perfect is different to different cultures. Even if we can figure out how to create "perfect" people, we'll have to ask ourselves as a society whether we should use this technology for that purpose.
stephanie-westview high
is athleticism learned or inherited?
     Dale Lea, R.N., M.P.H., C.G.C: A person's atheletic abilities are due to multiple factors including body type, hand eye coordination, and naturally dedication and practice. Genetics may influence some of these factors, as any coach can tell you "Let me win. But if I cannot win, let me be brave in the attempt."
raymond and deedee, fdhs maryland
is athleticism learned or inherited?
     Dale Lea, R.N., M.P.H., C.G.C: A person's atheletic abilities are due to multiple factors including body type, hand eye coordination, and naturally dedication and practice. Genetics may influence some of these factors, as any coach can tell you "Let me win. But if I cannot win, let me be brave in the attempt."
raymond and deedee, fdhs maryland
I was wanting to make a fun, genetic/DNA themed treat for today. I thought of Mendel Pea soup & double helix bread sticks, any other ideas?
     Sarah Harding, M.P.H.: Those are great ideas! Who else has ideas for genetically themed treats?
Is the technology availible to alter our own genes?
     Belen Hurle, Ph.D.: This kind of technology is already available when it comes to altering the genetic makeup of plants, bacteria or animals. There is interest in developing such technologies for medical applications, but it is hard to alter the genome of humans with the current technologies. This field of research is known as gene therapy, but it is in its infancy yet.
Guy Black, Carver High School, Houston Texas
what is the differences between transcription and translation?
     Carla Easter, Ph.D.: Transcription is the synthesis of DNA to mRNA. Translation refers to the conversion of mRNA into protein.
carmen, NY
In a hypothetical way, where someone has bad genes, could someone have super genes?
     Nate Sutter, Ph.D.: Yes, in a way. The action of a gene leads to some change in the body, whether observable or not. Many genes work quietly day in and day out and we never pay them any mind... unless we have a "bad" copy of the gene and it impacts our health. In the same way, we can imagine a new version of a gene that functions "better" than normal. But what do we mean by better? We really mean that *under certain circumstances* the gene functions better. It turns out that these circumstances (the environment) are hard to specify very well. Let's do a "thought experiment". Let's take a trivial example, a super hero we'll call "Mr. Flame" has a set of genes that makes his body temperature much higher than normal. This is a great super power because it enables him to survive in the middle of a snowstorm wearing just his swimsuit. That's great! He'll survive very well on a cold planet. But, to fuel his 180F body temp he has to eat constantly and consumes huge amounts of food. Let's say his environment changes: the weather warms up and at the same time food becomes limiting for his population. His "flame" genes don't serve him very well now. So, genes that were super great under one set of circumstances (environment) may not work well in a different environment.
John, Oakcrest HS
What, if any genetic diseases have been fully cured from the DNA technology?
     Don Hadley, M.S., C.G.C.: At this point in time, DNA technology has not been used to cure genetic diseases. The technology has helped understand the genetic contributions but has not been used as a cure. Many genetic diseases have been "treated" through the use of special diets, medications or modification of our habits. Finding a genetic cause for a disease (mutation) does allow the person to make decisions about their future and in some cases modify their health practices.
Jessica, Delaware
can you raise a fetus entirely out of the body?
     Donna Krasnewich, M.D., Ph.D.: A human fetus cannot be raised, from the stage of fertilized egg, outside of the mother's uterus. However, a fetus that has developed inside of the mother that is born at 20-22 weeks of gestation, not the usual 40 weeks of gestation, can be supported by a neonatal intensive care specialists. Clearly these very immature infants are quite medically fragile. Also remember that the bonding that goes on between a mother and fetus during pregnancy is very important and should not be underestimated as an essential part of human development.
Shannon from Lousiana
how many chromosones are in spanish?
     Belen Hurle, Ph.D.: CUARENTA Y SEIS! ventidos pares de cromosomas autosomicos, el cromosoma X y el cromosoma Y.
Bill from Beverly Hills
Are you well paid as a genetic counselor?
     Don Hadley, M.S., C.G.C.: There are always others who earn more, but I feel that my salary allows me to live quite well and enjoy other parts of life. If I had to pick a career again - I'd pick this one again - salary and all.
Speedy Baekster, Westview High
Which genetic disorders are able to be detected through prenatal tests, and how so?
     Dale Lea, R.N., M.P.H., C.G.C: There are currently a number of genetic disorders that can be detected through prenatal tests. Prenatal screening tests involve taking a blood sample from the pregnant woman and measuring proteins to identify increased risk for Down syndrome and open spinal defects. When the screening test indcates an increased risk, the pregnant woman is offered further testing such as amniocentesis and high resollution ultrasound examination. There are also genetic tests that can be done on fetal tissue taken from the pregnant woman as early as 10 weeks of pregnancy for genetic conditions such as cystic fibrosis, Tay-Sachs disease, certain types of muscular dystrophy and more. In these situations, the particular gene mutation that causes the disease needs to be known.
Bratis Lavaglia-Garfield, NJ
How many mutations does everyone have on average?
     Nate Sutter, Ph.D.: When a sperm or egg cell is produced the DNA has, on average, about 35 differences compared to the chromosomes in the father or mother. But the majority of the time, these mutations will occur in DNA regions that make no evident change to the organism.
Andrew and Pat- Groton

Information - Moderator Jennifer Sloan, Ph.D., a genetic counselor in the Genetic Disease Reserach Branch at NHGRI, has just come into the chat room.

Information - Moderator Barbara Fuller, J.D., the Deputy Ethics Counselor and the NHGRI Assistant Director for Ethics, has just joined the chat room.

My parents were straight A students, but I always struggle with school. Is this because of DNA?
     Colleen McBride, Ph.D.: Genetics is only part of what influences our intelligence. There are a number of other possible explanations for why you aren't having as easy a time with school as you think your parents did. Just to name a few possible other factors that might influence how one does in school for you to consider: 1) how performance is evaluated, 2) school environment, 3) the subjects, and 4) personality. The point is that there are a lot of external environmental factors that influence behavioral characteristics besides genetics.
Patrick Callaway, Delaware
I've been interested in a job in the DNA field. What can I try out?
     Vence Bonham, J.D.: There are many different types of careers and jobs in the field of genetics and genomics. My job is to lead our public education and community outreach programs. I also continue to conduct research at NHGRI studying the social implications of genomics for the public. There are many basic and clinical careers available. There are many careers and jobs that you can "try out". It is about getting the appropriate educaton and training. You may want to look for a summer internship working with someone in the field of genomics to learn more.
Dan Johnson... GHS

Information - Moderator Vence Bonham, J.D., the chief of the Education and Community Involvement Branch, is in the chat room.

what determines if you have a genetic disorder?
     Dale Lea, R.N., M.P.H., C.G.C: All diseases have a genetic component. Some genetic disorders are caused by a change one or both genes of a pair and are inherited from a parent. Other genetic disorders are caused by a change in a gene that happens spontaneously in that individual and are not inherited. So you can inherit a genetic disorder from one or both of your parents, or a genetic disorder can occur spontaneously in a person.
winston tolliver shcool without walls
How much do we know about the DNA sequences of other species?
     Belen Hurle, Ph.D.: A lot. There are tons of genomes completely or partially sequenced. Today the genome of a bacteria can be sequenced in a week or so. Vertebrates are more challenging, but some that have been sequenced by now are dog, mouse, rat, macaque chimpanzee, cow, or chicken to name a few. In my lab some people look at genomic sequence of very exotic organisms such as condor, whale, or bat. Each organism's genome hides the secrets for a different adaptation. The more genomes you look at and the more you compare with each other, the more you learn about biology.
I love genetics, but movies like GATTACA scare me. What do you suggest we do?
     Vence Bonham, J.D.: GATTACA is fiction. We need students that are interested in careers in genetics and genomics including policymakers and researchers who study the social issues of genetics and genomics. Follow you passion!
Pheet Thatare Griddley
This seems fun answering questions all day...does it ever get boring?
     Belen Hurle, Ph.D.: We are getting great questions and we are pretty entertained down here! We still have three hours to go.
Dr. McBride, do you find that your religious or political beliefs ever conflict with your job?
     Colleen McBride, Ph.D.: Actually, I have the good fortune of doing research on a topic that I feel is very in-step with my values. I do research to learn how to give people genetic risk information in ways that help them stay healthy. The great combination for me is that I have a lot of fun doing the work I do and I think it is socially valuable. So, no I don't find that my personal values are ever in conflict with what I do.
Miranda, Baltimore MD
If my grandfather and my mother has high blood pressure then will I ?
     Dale Lea, R.N., M.P.H., C.G.C: If your grandfather and your mother both have high blood pressure, you may have an increased risk for developing high blood pressure, but this family history does not mean that you will automatically develop high blood pressure. You should make your doctor aware of this family history so that you can be followed for that possibility.
Michelle John Hanson MS
Mathematically speaking, wouldn't the amount of combinations of A's, T's, C's, and G's run out? And people would start to look exactly like people who have already lived?
     Nate Sutter, Ph.D.: There are about 3 billion base pairs in the human genome. Out of these, about 10 million potentially vary from one person's genome to another. That turns out to be an enormous amount of diversity. Let's take a small example, a stretch of 5 bases, 'NNNNN'. Let's say the first position can be either A, C, G, or T. That's four choices. And same for the second position. So there are 4 * 4 ways to 'write' the first two nucleotides. That's 16 different ways to write just two bases! For a five base stretch you could potentially write 4 * 4 * 4 * 4 * 4 different sequences. I don't have a calculator handy so I'll let you figure out the answer. For a 100 base stretch there are an incredibly huge number of ways to write that sequence. There is a tremendous amount of information in your chromosomes!
Cj Bascom, GDRHS MA
What are the risks of genetics tests??
     Don Hadley, M.S., C.G.C.: We do have concerns about genetic testing since it is still a relatively new type of test that provides information not only about the person but as well the close relatives of that person. Studies are underway to help us learn more about what concerns people have about genetic testing as well how they feel after having a genetic test done. Many are concerned about whether insurance companies might use the information against them by denying people insurance or making them pay more if they are found to have genetic risks. We have much more to learn about this issue. You can read more about this topic at the following web-site;
Tyler, John Hanson MS
What is the most difficult ethical dilemma you have encountered in your work?
     Barbara Fuller, J.D.: One of the most common ethical dilemmas - if not the most difficult - is a person's desire to share their genetic information with their healthcare provider, and their desire to keep their information private. Sharing the information with their healthcare provider can have profound implications for an individual's health, but it can also mean the insurance company and the employer also have the same information. Legislation has been enacted in many states to protect genetic information, but there is no overall Federal legislation.
Shannon Hudson, Crawfordsville, Indiana
Has there been a good response to the on line chat today?
     Sarah Harding, M.P.H.: We have had a wonderful response in the DNA Day chatroom! We are all working very hard to answer as many questions as we can get to before 6pm. Many of the questions we've received have been thoughtful and have created discussion online and even in this room! It has been a pleasure to find out what students are curious about with respect to genetics.
melody gravett
What is Mendelian Inheritance?
     Carla Easter, Ph.D.: Mendelian inheritance (or Mendelian genetics or Mendelism) is guided by a set of rules that underlie much of genetics developed by Gregor Mendel. Mendel's first two laws: ? The principle of segregation (First Law): The two members of a gene pair (alleles) segregate (separate) from each other in the formation of gametes. Half the gametes carry one allele, and the other half carry the other allele. ? The principle of independent assortment (Second Law): Genes for different traits assort independently of one another in the formation of gametes.
Kelci-John Hanson MS
What types of disease are carried on the X chromosome?
     Dale Lea, R.N., M.P.H., C.G.C: There are a variety of genetic disorders that occur as a result of a gene mutation on the X chromosome. Examples include hemophilia, Duchenne muscular dystrophy, Fragile X syndrome, and many types of X-linked mental retardation.
Kelci-Hughesville, MD

Information - Moderator Good afternoon! On behalf of Dr. Francis Collins and the rest of the National Human Genome Research Institute, I would like to offer congratulations to the winners of the 2006 American Society of Human Genetics DNA Day Essay Contest. The DNA Day essay contest was sponsored by the American Society of Human Genetics (ASHG)?and Applied Biosystems.??The winning essays were selected by ASHG.? Winners will receive cash prizes, and the 1st place winner for each essay question will win funding for equipment for his/her classroom.

Information - Moderator Here are the winners for this year's essay contest: First Place: Jocelyn Lam (Grade 12); King's High School; Bothell WA Second Place: Jeffrey Tseng (Grade 11): Montgomery Blair High School; Silver Spring MD Third Place: Alexander Long (Grade 11); Worthington Kilbourne High School; Columbus OH

Information - Moderator For Question 2: If you were a genetics researcher, what would you like to study and why? First Place: Alaina Hahn (Grade 9); Tualatin High School; Tualatin, OR Second Place: Lauren Kennedy (Grade 12): Archmere Academy; Claymont DE Third Place: Laura Neese (Grade 12); St. John Villa Academy; Staten Island, NY

Information - Moderator The winning essays will be posted on the ASHG website at Congratulations to the winners!

What is a genetic counselor?
     Jennifer Sloan, M.S., Ph.D.: A genetic counselor is a health care professional who usually has a Master's degree in Genetic Counseling and who is board certified. Genetic counselors work with individuals with a genetic condition or at risk for a genetic condition. A genetic counselor helps educate the family about a specific condition and cope with the illness. They also discuss risks to family members, testing options and treatments and work as part of an interdisciplinary team that may include geneticists, obstetricians, nurses, social workers, nutritionists etc.
Are the genetic sequences for any other organisms currently in the mapping phase?
     Tyra Wolfsberg, Ph.D.: As you're probably aware, the human genome sequence was completed in April, 2003. But there are many other organisms whose genomes are either completely sequenced, or in the process of being sequenced. These include chimp, mouse, dog, chicken, opossum, and zebrafish.
Why do some diseases start in someone when their family never had it before?
     Don Hadley, M.S., C.G.C.: This is a great question that has many answers. Sometimes a disease can happen as the result on a new mutation in a gene that has not been present in any family member before. Other times it may occur because it is the result of an autosomal recessive condition which means that each parent contributed one copy of a gene which requires two copies to express itself. Many times, no one else in previous generations have had the condition or disease. Yet another explanation is that the disease is the result of one person having a particular combination of genes in addition to having certain environmental infuences (diet, toxic exposure, etc.) which lead to the development of the disease and no one elase has that same . Sometimes it may be the result of variable expression of the disease (which means that the disease does not always look the same from one person to the next) or reduced penetrance (not everyone who has the mutation shows symptoms). As you can tell, there are many possible answers to your question. I invite you to research these and come up with other possible answers. Good luck.
Rebecca, Alexandria Virginia

Information - Moderator Joining us now is Tyra Wolfsberg, Ph.D., a bioinformatics expert with NHGRI's Division of Intramural Research.

How does the tRNA know what amino acid to get?
     Carla Easter, Ph.D.: Due to the structure and charge of each individual tRNA, they can only bind to a specific amino acid. In other words, only one tRNA molecule binds to only one type of amino acid.
Beau Liljenquist
is it possible your gene can change over time?
     Carla Easter, Ph.D.: Over time, there is a chance that mutations or changes can occur in a gene. This can be due to errors in replication or possible mutagens (agents that cause mutations).
hung tran , westview
How often do you use pedigrees in genetic counseling?
     Don Hadley, M.S., C.G.C.: Every single time! We start by collecting family medical history and drawing a pedigree with every family we meet. It is a simple and inexpensive way to determine what medical risks a person may have even when genetic testing is not available. We are trying to get all doctors to collect family history information for all of their patients. Go to to construct your own pedigree. By the way - let your doctor know about this site! Thanks for asking.
can I get the color of my eyes changed genetically?
     Belen Hurle, Ph.D.: No really. Try contact lenses!
ethan poindexter, from Concordia Academy
At this time the are of biotechnology is very complex and always changing. In the future the public will need to be informed. So how do you propse to inform the people on the affect that this science might have on them?
     Vence Bonham, J.D.: We will need to use multiple strategies to inform the public. The media is extremely important in disseminating information. We also need educators to develop new models to educate the public about science, and its role in society.
Madeleine Ledford, William Monroe
Is mental retardation a result of mutation?
     Jennifer Sloan, M.S., Ph.D.: There are many different causes of mental retardation including both environmental and genetic factors. Mental retardation is a feature of many genetic syndromes. These syndromes can be caused by a mutation in a single gene or by missing or extra chromosomes or sections of chromosomes. One example where mental retardation is caused by a mutation in a single gene is Fragile X syndrome. An example where mental retardation is caused by an extra chromosome is Down syndrome.
llama, charlesburg
What is the average mutation rate of human DNA?
     Belen Hurle, Ph.D.: The sperm and the egg have about 20-25 new mutations each. This means that you were born with some 50 de novo (new) mutations in your DNA, or new variations that your parents didn't have.
Ranjit Madtown
Why can private companies be allowed to patent DNA sequences? Should it not be public domain?
     Barbara Fuller, J.D.: The sequence of the human genome is in the public domain. You can locate the entire sequence at In order for a company to patent a sequence, a company has to show they know a use for the sequence which means that it is not just the straight sequence they are attempting to patent. Allowing patenting actually is a way to provide an incentive for companies to invest in research. Keep in mind that patenting does not have to mean exclusive use - the patent holder can grant licenses to others so they can also do research on the same sequence.
Rafael from Washington, D.C.
What equipment do you use to study genetics?
     Tyra Wolfsberg, Ph.D.: The type of research that I do is called Bioinformatics. Bioinformaticians use computers to study genetics. We often start with sequence data that was generated as part of the Human Genome Project. Then we run specially designed computer programs to analyze the sequences. Often, the results of our research are available over the internet.
Emily MA
If I was to have a child, for example, what are the chances of my child being born with a genetic disorder such cystic fibrosis if no other person in my family has had it?
     Jennifer Sloan, M.S., Ph.D.: The risk to have a child with cystic fibrosis depends on the ethnic background of the parents. Cystic fibrosis is most common in the Caucasian population. The chance is approximately 1 in 2500 for a child born to Caucasian parents. In the general population, there is a 3-5% chance with every pregnancy that a child will be born with a birth defect.
Piotr Lukasz Kilebassczki Jr.
If there is a genetic disease that runs in your family, does that mean that your are going to surely get it?
     Don Hadley, M.S., C.G.C.: No, having a genetic disease in the family does not always mean that a person will get the disease in their family. But the answer to your question depends on how that disease is inherited and what strategies are availble to prevent the disease from occuring. For example, Huntington Disease is a an autosomal dominant disease which means that if a parent has the disease their is a 50% chance each child they have will develop the disease. In contrast, sickle cell disease is an autosomal recessive disease. A person that has this disease is unlikely (but still possible) to pass it along to their children unless their partner also carries a sickle cell gene mutation. Other diseases that are inherited have medical screening that can prevent the disease from occuring even if the person has the genetic mutation for it. For example, some people who have genetic mutations that increase their risks for cancer can undergo cancer screening that in some cases can prevent cancer from occuring - the best example of this is for colon cancer. We are learning more every day about ways to prevent genetic and inherited diseases from occurring in families with those diseases. Stay tuned.
Lymiracle Hill, Hogdson Vo-Tech
What kind of education do I need to become a cytogeneticist?
     Belen Hurle, Ph.D.: Try biology, chemistry, computers, and imaging if you have a chance. Don't worry about getting a very specific training just yet. Most scientists start with a pretty generic training and get sub-specialized as they progress along in their careers.
What year was DNA discovered?
     Carla Easter, Ph.D.: Many people and experiments led to the discovery of DNA. In the 1800's, Gregor Mendel working with pea plants discovered the principles of inheritance. The discovery that DNA was the genetic material of an organism was discovered in the 1940s. Oswald Avery and his co-workers discovered that DNA was the "transforming principle" or the molecule that caused a bacteria to acquire new traits. These experiments led ot the discover that the genetic material of a cell was found in the DNA. The physical structure of DNA was discovered in 1953 by James Watson, Francis Crick, and Rosalind Franklin.
Hugh Georgie, from OB City
Why is sickle cell disease spreading so fast?
     Vence Bonham, J.D.: Sickle cell disease is a mendelian genetic condition. Two individuals with sickle cell trait have a one in four chance of having a child with the disease. It may seem to you that sickle cell disease is spreading fast because of people you know may be at higher risk for the genetic condition. Also better health care may identify individuals earlier with the disease. There is research being done at the National Institutes of Health to develop new therapies for individuals with the disease.
Chase ,Maryland
who are the winners from the contest?
     Sarah Harding, M.P.H.: Here is a quick recap of the winners of the ASHG essay contest:

Question 1: Why is it important for everyone to know about DNA and genetics?

First place: Jocelyn Lam (Grade 12); King's High School; Bothell WA 98011

Second place: Jeffrey Tseng (Grade 11); Montgomery Blair High School; Silver Spring MD 20901

Third place: Alexander Long (Grade 11) Worthington Kilbourne High School Columbus OH 43235

Question Two: If you were a genetics researcher, what would you like to study (and why)?:

First Place: Alaina K. Hahn (Grade 9); Tualatin High School; Tualatin OR 97062

Second Place: Lauren Kennedy (Grade 12); Archmere Academy; Claymont DE 19703

Third Place: Laura Neese (Grade 12); St. John Villa Academy; Staten Island NY 10306

Mrs. trinkle
why do some genes mutate while other genes stay normal?
     Tyra Wolfsberg, Ph.D.: Each time that the cells in your body divide to form new cells, the DNA inside those cells has to replicate as well. At a very low rate, the DNA mutates when it replicates. There's an equal chance that these mutations will happen anywhere in your genome. Most of the time, these mutations will have no affect, as they don't change the sequence of a gene. But, if a mutation happens to occur in a gene, in a type of cell that gene works in, then the mutation will have an effect on your health.
Elizabeth Michigan
H? uma maneira impedir disorders genetic ou come?ar talvez a cirurgia repar?-la?
     Belen Hurle, Ph.D.: Cirurgia corretiva n?o pode curar desordens gen?ticas, mas em alguns casos pode ajudar as pessoas com problemas geneeticos a ter vidas mais saud?veis, por exemplo com a corre??o de uma fenda palatina, ou malforma??o card?aca. As vezes mudan?as no estilo de vida podem tamb?m melhorar a sa?de do paciente com condi??o gen?tica, como uma dieta especial para quem tem uma doen?a gen?tica do metabolismo.
Aldina, brazil
First off i just wanted to say that, Mrs. Easter, i really enjoyed your speech at our school yesterday. Do they expect that the entire genome will be sequenced AND all the functions of the genes be known before the end of the decade?
     Carla Easter, Ph.D.: That's a great question. There are several labs continuing to work on the completion of the sequence. With the advances in genome sequencing techniques, I am optimistic that we will see some of the more difficult regions of the genome sequence and the function of the corresponding genes solved in the next ten years.
Ben plotsky Wootton High School

Information - Moderator Ashley Weedn, a doctor with NHGRI's Education and Community Involvement Branch, is now joining us. So, send your questions in!

Barbara Fuller, What kind of college and training did you go through to become the NHGRI Assistant Director for Ethics?
     Barbara Fuller, J.D.: I have a law degree, and I have a background in healthcare administration. It has been very helpful to have both the law degree and the experience in healthcare administration because I can draw on both in performing my job at NHGRI. I use the law degree when trying to decipher the ethics rules and regulations, and I use my background in healthcare administration when reviewing the individual and unique ethical situations that need resolution. Actually, a wonderful job in an ethical organization!
Rory Everett, WA
Out of the the 25,000 genes that have been discovered, how many have been identified?
     Belen Hurle, Ph.D.: Some human genes have been studied for a long time and we know a lot about them. Some genes are just computer predictions waiting for somebody to verify that they really exist and do something through real experiments. It can get pretty complicated to study a gene that is expressed in very low levels, in a tiny population of cells, or for a short period of time.
Nina McCoy, from MD
what exactly is an allele
     Carla Easter, Ph.D.: An allele is one of the variant forms of a gene at a particular locus, or location, on a chromosome. Different alleles produce variation in inherited characteristics such as hair color or blood type. In an individual, one form of the allele (the dominant one) may be expressed more than another form (the recessive one).
Izzy Los Angeles
Do you enjoy your job?
     Tyra Wolfsberg, Ph.D.: Yes, I do. When I was in college, I was working on a project that involved analyzing the A's, C's, G's, and T's in a DNA sequence. There weren't many computer programs around to do this type of work, like there are today, so I spent a lot of time either looking at the sequences, or writing them on a piece of paper. I realized that I really enjoyed staring at these letters and trying to make sense of the patterns that they spelled out. In graduate school, I moved on to looking at protein sequences, which have 20 different letters. I've been lucky to find a job doing bioinformatics, where I can continue to look at these letters, both in DNA and in protein, and actually get paid for it.
Joscelyn Sandoval Los Angeles
Is Alzheimer's disease hereditary? Is there a way to lessen the chance of getting it? Is there a way to get rid of it or control it?
     Jennifer Sloan, M.S., Ph.D.: Alzheimer's disease is hereditary in only a very small number of families where there is a single gene mutation. In these families, the Alzheimer's disease is usually earlier in onset (before age 60-65) and follow autosomal dominant inheritance (children of an affected individual have a 50% chance of developing the disorder). In the majority of families, Alzheimer's disease is not hereditary and children of affected individuals are not at high risk. It is unknown what causes the disorder but most likely both genes and environmental factors play a role. Currently there is no cure for Alzheimer's disease. More information can be found on
Where is DNA located?
     Tyra Wolfsberg, Ph.D.: DNA is located in the nucleus of each of the cells of your body, except for red blood cells and specialized cells in the lenses of your eyes. Each cell has almost exactly the same DNA.
erin, Maryland
in the future would we be able to pick out how your child, or yourself could look, by changing their DNA?
     Barbara Fuller, J.D.: The real question is whether you would want to pick out how your child could look. Certainly, it is feasible that we could do this in the future, but that doesn't mean that we would - or should - alter the DNA to change the appearance of your child.
Jessica- Delaware
This question is directed towards Dr. Hurle. What are the Spanish translations for a few DNA-related terms? For example, how do you say deoxyribonucleic acid in Spanish? Thanks.
     Belen Hurle, Ph.D.: Acido desoxirribonucleico (ADN)! Did you know that our Institute has a talking glossary with translations and definitions for the most common genetic terms? Check out the Spanish version at:
D. Lawrence from New York
How would one go about collecting DNA at a crime scene?
     Les Biesecker, M.D.: There are many ways to collect DNA from a crime scene. A common one is to identify (with fluorescent light) blood stains on absorbent materials such as fabric or clothing. Then, one can chemically separate the blood cells and then the DNA from those blood cells, from the fabric. This DNA can be used for genetic profiling to match to DNA samples from victims or suspects.
Why do some families have more twins born than in other families?
     Don Hadley, M.S., C.G.C.: There are studies which are focused on understanding the genetic components of twinning. These studies provide evidence that genetics plays a role in the occurence of twinning although I don't think specific genes have been found. Families that have non-identical twins (fraternal) seem to have a greater genetic component than those with identical twins.
Deborah, Edna HS
What kinds of people are there in this chatroom, and how many are there of you? What kind of work do you do? Do you have fun working with genetics?
     Larry Thompson: The chat room has been staffed all day by various professionals from the National Human Genome Research Institute, a part of the National Instiutes of Health. We've had physicians, ph.d-scientists, nurses, lawyers, genetic counsellors, computer experts keeping the chat room up and running, writers and editors directing the flow of questions to the right expert for answers. We come in every age, shape and size. The ages range from the early 20s to the late 50s. They come from all over the country -- and a few from other countries. We've had basic scientists studying the details of genetics and genomics, physicians who take care of patients and who try to advance medical knowledge in the process, and bio-information experts who translate the new findings into scientific advances. Those of you have are participating in or watching today's chat have heard from some of the nation's leading scientists in this field. And they have had a blast doing it; we're sitting in a converted conference room with a big U-shaped table loaded with laptops all hooked into the web. Sometimes the room has been noisy as people discuss the answers to sometimes incredibly quiet as everyone works hard to respond to your questions. So far, we think it has been a tremendous success -- and hope you feel the same way.
Lina, Los Angeles Cali :)
Are migraine headaches related to a person's genes and if so, do you think it is possible to find a cure for them?
     Ashley Weedn, M.D.: Hi Jason, a migraine is a type of headache that is thought to be a multifactorial condition - due to a complex interaction of multiple genetic and environmental factors. We know genetics plays a part in migraines because family history is a risk factor for migraines. Regarding a cure, genomics researchers are in the process of understanding the genetic factors in multifactorial conditions, which will lead to better prevention and treatment options.
Jason - Kamiak High School....Mukilteo
biology seems boring! what makes this interesting to you at all? i mean its something we cant even see
     Carla Easter, Ph.D.: I think there are so many interesting things to study in the field of biology. It is not just about the chemistry and the molecules and the stuff we can't see. Although, I think that stuff is pretty cool. Imagine how sick some organisms that we can't see, viruses and bacteria, can make us. To me, biology is all bout life and how living organisms interact. It's also about how living things adapt and change in order to survive. I find this all very exciting because humans are organisms that are constantly chnaging and adapting.
bio is boring
Are there any benefits in DNA profiling?
     Les Biesecker, M.D.: There are many benefits to this. A recent example is the use of DNA profiling to identify remains of victims from the World Trade Center 9/11 attacks. The Medical Examiner of NYC used DNA profiles to identify hundreds of victims that otherwise would not have been identified. For more details see: Science. 2005 Nov 18;310(5751):1122-3.
Loren Caddell; Birmingham, Al
What are the pros and cons of seeing a genetic counselor? If your baby is develpoed enough to take DNA is there even a way to prevent it from a disease it may be carring? And what specific genes are they able to change at this point in scientific advancement?
     Jennifer Sloan, M.S., Ph.D.: A prenatal genetic counselor can help a couple during a pregnancy or planning a pregnancy learn about the risks and testing options for genetic conditions based on family history, maternal age, and ethnicity. Currently, there are no specific genes that we can change prenatally to prevent a genetic disorder.
Sophie-Claire, Alabama
For how many people are in the world, how aren't there 2 people with the same DNA?
     Belen Hurle, Ph.D.: Well, identical twins have the same DNA. For the rest of us, technically it is not impossible, but statistically is VERY unlikey that two people would have the same DNA just by chance.
Holly Croll, Westview
Do you ever find your job boring or is it your dream job?
     Ashley Weedn, M.D.: Hi Katie, I'm actually still in the process of my clinical training (just finished medical school) and often am overwhelmed by the amount of information that I need to know to best take care of my patients, which does not leave any time for boredom! In fact, taking care of patients is always stimulating and inspiring!
Katie Mercado, Los Angeles
What do people use DNA samples for other than finding out who the real father is of the baby?
     Don Hadley, M.S., C.G.C.: There are many other uses that DNA samples can provide besides determining paternity. Some examples include determining what diseases a person might be at risk for developing during their life or knowing what medications will be most effective in them. Recently, DNA was used to help identify human bodies found following catastrophes like Hurricane Katrina. I
Jasmine, Washington D.C.
Does each gene have its own sequence of letters and if so how do you tell which gene the sequence represents?
     Tyra Wolfsberg, Ph.D.: Yes, each gene is defined by its unique sequence of letters. When someone discovers the sequence of a new gene, they deposit that sequence into a publicly accessible database, such as one maintained here at the NIH, called GenBank ( There are some online computer programs that you can run to compare the sequences to each other. So, if you're doing a lab project and you generate some new DNA sequence, you could compare it to the existing sequences in GenBank to learn more about it. GenBank currently contains over 100 billion base pairs, so there's a good chance that your new gene is similar to one that's already been discovered.
Rebecca, Alexandria Virginia
Obviously all of us students have learned a lot today. I was wondering if the scientists/doctors have as well?
     Carla Easter, Ph.D.: Most definitey! We are learning more and more each day. The sequencing of the human genome gave us more information to work with and more questions to answer. Scientists and doctors are taking advantage of the discoveries and applying them to the diagnosis and treatment of diseases. The more discoveries we make, the more physicians and scientits have to learn about applying them.
Pheet Thatare Gridley
Do you believe everything is related to genes and genetics?
     Vence Bonham, J.D.: No. Environment Matters! The National Institutes of Health is conducting a number of studies to learn more about the role of genes and environment in human health.
What would you say is the biggest threat of bioinformatics?
     Tyra Wolfsberg, Ph.D.: Most of bioinformatics work is done on a computer. So the biggest threat to bioinformatics research is the computer crashing before you've saved your data!!
Amy--William Monroe High School
Is it possible for DNA to mutate on its own?
     Les Biesecker, M.D.: It is not only possible, it is essentially universal. Every offspring has a number of genetic differences when compared to their parents. This is how genetic variation is generated. Most such variations are harmless or cause no recognizable effect. A small number do. Sometimes the recognizable effects occur in the first holder of the mutation (whom we call the "founder") or sometimes the recognizable effects are later recognized in their descendents.
Kaylynn, Moscow Russia
Are viruses living organisms and do they have DNA?
     Carla Easter, Ph.D.: This is a great question and one that has been debated for years. It all depends on how you define "living." Some viruses have DNA as their genetic materials and others have RNA as their genetic material.
toby, westview
Why is DNA day today, April 25th? Is it always on April 25th and who started it?
     Sarah Harding, M.P.H.: Hello, thanks for the question! DNA Day is celebrated today because April 25 was the day the sequence was published in 2003. April 2003 also marked the 50 year anniversary of the description of the double helix by Watson and Crick. A few organizations including NHGRI were a part of the initial celebration in 2003, but now DNA Day is celebrated by many different groups.
Setha Groton
Bioinformatics is the studies of computer technology in the relationship with coding the genetic sequence, what field of science would you classfiy this as?
     Tyra Wolfsberg, Ph.D.: There are two main types of people who get involved in bioinformatics research--computer scientists, and biologists. We need computer scientists and programmers to develop the algorithms and programs we need to analyze the sequence data. But we also need biologists to help interpret those data.
Erin Jones
what do you dislike most about your job
     Belen Hurle, Ph.D.: For the most part I like what I do. Sometimes I have to spend time in tedious tasks such a preparing large batches of sequences for computer analysis.I don't like that. I like that my schedule is very flexible but the flip side is that sometimes I work over the weekends or late at night. I don't enjoy that much either, specially if it is a nice day outside.
Rebecca Wethington Kentucky
Can genetics "skip a generation" ?
     Don Hadley, M.S., C.G.C.: Sometimes it can appear that an inherited disease "skips" a generation in a family because the person in between does not have the disease. They may still carry the mutation, but not "show" the disease or they express it in a slightly different way. In other cases, there may be a combination of gneetic and environmental factors that influence whether one family member gets a disease and others don't. One needs to be careful in interpreting the family history because these kinds of situations can influence what risks exist for our families to develop disease
Are there any known substances that could replace DNA and replicate/function the same way it normally does?
     Carla Easter, Ph.D.: To my knowledge, there are no other molecules that can replace the exact function of DNA. There are retroviruses like HIV that have RNA as their genetic material. This RNA can be replicated and inherited by the viral progeny, but these viruses use DNA as an intermediate step in their life cycles.
Adam D. from Florida
what was the first organism of DNA?
     Belen Hurle, Ph.D.: Scientists have been looking for a while after LUCA, the Latest Universal Common Ancestor. However, at the moment, the answer to the question is: We do not know, and we may never know, because there may have been no single ancestor, but a mess of gene-swapping early cells. It's not a comfortable answer, but it may very well be right!
Jay Blumberg, WESTVIEW
How bad are the symptoms for cystic fibrosis?
     Ashley Weedn, M.D.: Cystic fibrosis is a disease that causes progressive damage to the respiratory and digestive systems. In addition, it can also cause infertility in men. For more information on specific symptoms, check out the NLM Genetics Home Reference page.
Lymiracle Hill, Hodgson Vo-Tech
Why is there a better chance of men (XY) getting a sex-linked disease. I would think that women (XX) would have a better chance.
     Les Biesecker, M.D.: Great question. It is more likely for women to have a sex linked mutation than it is for men, as women have twice as many X chromosomes. So in that sense you are correct. However, it is more likely for men to have the DISEASE that is caused by the mutation. This is because most mutated X genes only cause a disease if there is NOT another normal copy of the gene on the other X chromosome. Of course, typical males never have this second copy of the gene, so that means that the disease will manifest if they have the mutation on their one (and only) chromosome. On the other hand, females almost always have another normal copy of the gene on their other chromosome and the presence of this other normal gene "rescues" them, so they don't have the disease. However, they have a 50% chance with each male offspring that the child would be affected with the disorder.
AudreyAnna IL
What tests do they run to find out if you have Fragile X Syndrome?
     Jennifer Sloan, M.S., Ph.D.: A laboratory can determine if a person has Fragile X syndrome by using PCR (polymerase chain reaction) and Southern blot on a person's DNA sample. These methods are used to look for an expansion of CGG repeats in the FMR1 gene. When the FMR1 gene contains >200 repeats, a male would receive the diagnosis of Fragile X syndrome.
Alyssa, Lyon County Middle School
If a genetic disease runs in your family, how long does it take for you to develop that disease?
     Don Hadley, M.S., C.G.C.: It depends on the disease - some occur earlier in life and others occur later. It also depends on whether or how the disease is inherited. Also - just because a family has an inherited disease does not mean everyone in that family will get the disease.
Lymiracle Hill, Hogdson Vo-Tech
What are some of the most common diseases that are x-linked?
     Les Biesecker, M.D.: Two common X linnked traits are color blindness and hemophilia. The most common type of color blindness is protanopia, which is an inability to differentiate red from green. Hemophilia is a disorder that causes one to have a deficiency of blood clotting. This trait is famously associated with several royal families, including those of imperial Russia and England.
taylor adams
My mother hates chocolate but I love it. My father loves chocolate just like me. Is there any way that I got my love of Chocolate from my father?
     Carla Easter, Ph.D.: To date, we have not discovered a specific gene for liking chocolate. Although, you and your dad's like of chocolate could have something to do with the genes involved in taste. Scientists are currently discovering and studying the genes that encode such proteins.
AudreyAnna, IL
What would happen if adenine paired with cytosine instead of thymine?
     Belen Hurle, Ph.D.: Most of the time the cell would detect the glitch right away and correct it before it gets passed on. But if the error is not corrected, one of the two DNA molecules will inherit the mutation. This may result in no problem at all, or a serious problem like a cancer depending on where the glitch happens.
Deanna, Birmingham, AL
Dr. Nate Sutter, Ph.D., in your explanation to the question asked about combinations of A's, T's, C's, and G's, wouldn't it only be 2*2 and so on because the pair only match one other, not all 4?
     Tyra Wolfsberg, Ph.D.: Dr. Sutter has already gone back to the lab, so I'll follow up on this one. As you're suggesting in your question, DNA is double stranded, and between the two strands, A pairs with T, and G with C. But what Dr. Sutter is talking about is what's happening on just one strand of the DNA. At the first position on one strand, you can have either an A, C, G, or T. Then at the next position on that strand, you can also have an A, C, G, or T. So that's 4 * 4, or 16, ways to write the first two nucleotides. And then the other strand of the DNA will be the complement of the first. So, if one strand of DNA has this sequence: AGCCGGTA the complementary sequence on the second strand will be: TCGGCCAT
Ashley, Westview
What websites would you suggest to find out more about DNA?
     Carla Easter, Ph.D.: There are several that you may fine helpful listed on the NHGRI website at
D. Lawrence from New York
how can i easily teach my students about the jobs of DNA so that they understand what goes on?
     Vence Bonham, J.D.: There are several resources available to students and teachers that describe genetic careers. Examples:; . The National Human Genome Research Institute is developing a new resource for students and teachers about genomic careers. Look for it next year!
John, Wellesley
If extraterrestrial life is found, what (in your opinion) are the chances that it will contain nucleic acids?
     Carla Easter, Ph.D.: Interesting question. In my opinion, the chances that extraterrestrial life will have nucelic acids is pretty good. This new nucleic acid may have a different composition than what we know on earth, but I believe it will be closely related to our own earthly nucleic acids.
D. Lawrence from Mars
Did scientists know where they were heading towards before they discovered DNA?
     Les Biesecker, M.D.: In some ways they did, in some ways they did not. At first, all they knew they were looking for was a material that transmitted traits from one bacterium to another. It turned out that material was not protein or carbohydrates, and turned out to be DNA. They certainly did not know much of anything about DNA until they figured out that it was the genetic material and then the research exploded and moved very fast. This is what is so exciting about basic research, things are discovered are a wonderful mix of the expected and the unexpected.
Angela, Westview
Why is my family constintly depressed? Does DNA effect someones depression?
     Don Hadley, M.S., C.G.C.: We are beginning to understand the contributions that genetics make to influence depression. But certainly genetics is not the only important factor that infuence whether a person experiences depression or not. We are working to understand both the genetics and environmental components so that we can effectively help people and families who struggle with depression. If you would like to learn more about this topic or talk about the issue further, you can e-mail and discuss your questions in more detail. Thanks for your questions.
Student in Delaware
The genes for schizophrenia appear to be scattered on many human chromosomes. Why is this?
     Jennifer Sloan, M.S., Ph.D.: Schizophrenia is most likely caused by a combination of several genes and environmental factors, not just a single gene. This is why there are many genes for schizophrenia scattered throughout human chromosomes. More information about the genetics of schizophrenia can be found at
Miranda, Baltimore
Which courses in a university would offer a better foundation if one would be interested in pursuing a career that involves bioengineering?
     Carla Easter, Ph.D.: Many universities have bioengineering or biomedical engineering majors. Typically, these majors include classes in engineering, biology, chemistry, physics, molecular biology, and other life sciences.
roxi, chicago
what would you consider the long term goal of genetic research? Where will genetics take us to in the end?
     Les Biesecker, M.D.: I consider the long term goal of genetic research to be the elucidation of the molecular mechanisms of human health and disease. Where I want to take it is to develop tools and techniques to accurately diagnose and effectively treat disease. Ultimately, it will take us where we, as a society, choose to go.
stephanie st. ignatius
how do you pick what questions to answer?
     Sarah Harding, M.P.H.: We have received over 2500 questions today. Though we've had a large room full of people working to answer these questions, we haven't been able to get to them all. Also, some of these questions overlap with one another in their topic. So we do our best to pick a representative group of questions as the day goes on, both in regards to topic and in geographic location from where the question was asked. Once DNA Day is over, the whole transcript will be posted online at You'll be able to scroll through the whole transcript, and use ctrl+f to search for specific answers to questions you might have asked, or topics you are curious about.

Information - Moderator The chat room is receiving a number of questions about the essay winners. The results were announced earlier today. Please scroll down to find the winners or use Control F to search for the results.

Are there any specific areas in the medical field that the genome project has benefited greatly?
     Les Biesecker, M.D.: Many areas of medicine have benefitted as the genome project has broadly accelerated investigations into the pathophysiology of disease. Another area that has benefitted enormously is that of rare diseases. Many rare diseases are now diagnosable because of the genome project and some of those now have treatments approved or being tested. The Genetic Alliance is have a major meeting this week to announce the progress that has been made in this regard. See:
Massiel P. Garfield High School
how much do you make a year?
     Alan Guttmacher, M.D.: Genetics researchers make anything from $40,000 to hundreds of thousands of dollars a year, depending upon what kind of work they do, how much experience they have, and where they work.
Miriam Hondu, Memphis TN
How much does a genome weigh?
     Phyllis Frosst, Ph.D.: According to Francis Collins MD PhD, director of the institute, a genome weighs 6.7 picograms per cell.
What is the genetic mutation for Muscular Dystrophy?
     Les Biesecker, M.D.: First, there are many forms of muscular dystrophy. One of the most common is Duchenne muscular dystrophy, which is caused by mutations in the dystrophin or DMD gene. Many different mutations have been described in this gene, nearly 700 according to the Human Gene Mutation Database (
Kimberly Tello- Houston, TX
How many changes are needed in the sequence of a gene to alter it?
     Carla Easter, Ph.D.: Great question. It is not always about the number of changes or mutations, it is about where and what kinds of changes. For example, multiple mutations may occur in the introns of a gene or the changes may not affect the amino acid sequence of the resulting protein. These changes are not as detrimental as changes that occur in regulatory or coding regions or cause a change in the reading frame. You can have a single mutation in a gene that causes a major change in a gene and is responsible for the onset of a genetic disorder like sickle cell anemia.
Tyler Fay Queensbury NY
Can you tell a person's race from DNA?
     Vence Bonham, J.D.: No. Race is a social construct and is not biological. You can learn about a person's ancestral background which may correlate with the person's self-identified race.
Brooke, illinois
what has been your most favorite question of the day?
     Phyllis Frosst, Ph.D.: I have to say, it's the jokester who asked if DNA stood for Dinosaur Nose somethingorother... it's seemed to give people here the most chuckles.
bob joe

Information - Moderator Two of our colleagues who were in the chat room earlier today have come back: Alan Guttmacher, a physician and deputy director of NHGRI has returned, along with Phyllis Frosst, the science policy analyst in the Policy and Program Analysis Branch.

What is the most controversial topic being researched and discussed today?
     Alan Guttmacher, M.D.: Controversy is in the eye of the beholder, but the most controversial area in biomedical research today may be stem cell research - not controversial so much in terms of the science, but in terms of the ethical and social questions that it raises.
Ryan R. from Kamiak High School in Mukilteo, Washington

Information - Moderator Joining us in the chat room for the first time today is Teri Manolio, a physician and a Ph.D.-researcher and senior advisor to the director for population genomics.

This question is for anyone - What has been your favorite question today out of all 2500?
     Sarah Harding, M.P.H.: For me, I have enjoyed reading questions from students exploring the implications of genetics, such as ethical and social issues. But many of the questions we've received have been very thoughtful and fun to explore.
Tyler Wilson a.k.a Tbone - Westview High
Do identical twins have the same DNA??
     Kris Wetterstrand, M.S.: Yes, identical twins have the same DNA.

Information - Moderator Kris Wetterstrand, a program analyst specializing in sequencing and the ENCODE project, has joined the chat room.

Is pancreas cancer genetic and if so, do we know what chromosome it can be found on?
     Ashley Weedn, M.D.: Hi Jake, all cancers have a genetic basis; however, not all cancers are hereditary. Current thought is that a small percent (5-10%) of pancreatic cancer is familial, similar to breast cancer in that 5-10% of breast cancer is due to mutations in BRCA1 and BRCA2. To date, there is not a specific chromosome or gene identified for familial pancreatic cancer - research is underway though to find which genes may be involved in increasing the risk for pancreatic cancer.
Jake, Crawfordsville

Information - Moderator And finally, for this hour, Kim Kaphingst, an investigator in the Social and Behavioral Research Branch and head of the Communication Research Section, has joined the chat room.

Is it possible for two people who are not related to have similar DNA?
     Teri Manolio, M.D., Ph.D.: It depends a little on what you mean by "not related," since in a way all humans are related by being members of the same species. In general, the degree of similarity of DNA increases the more closely that two people are related biologically. It's possible for people who are not related to have some of the same DNA markers, but if they have many DNA markers that are the same they are likely to be related.
If someone has PKU, can they ever eat foods with phenylalanine later in life? Can gene therapy work with people with PKU?
     Alan Guttmacher, M.D.: They can eat foods with some phenylalanine, but how much varies from individual to individual. Some older folks with PKU can tolerate almost no phenylalanine, while others can eat a fair bit without difficulty. Gene thearpy is not yet useful for those with PKU, but we think it should be in years to come.
A.I. duPont H.S.
In terms suitable for 10th grade biology students, please list how the study of DNA can be used to support the theory of evolution by natural selection.
     Les Biesecker, M.D.: The genome project has generated large amounts of data called "comparative genomics". To do this, scientists study the DNA sequences of different organisms. It turns out that the DNA sequences of closely related species (e.g., humans and chimpanzees) are similar and the DNA sequences of distantly related species (humans and fruit flies) are less similar. But, even distantly related species have startlingly similar DNA sequences. For example, a set of genes called the HOX genes are very similar even in humans and fruit flies. These genes are the signals that organize the head to tail aspects of the developing embryo. As flies and humans have the same basic organization (head-neck-chest-abdomen) the mechanism to set that up (the HOX genes) are quite similar. These relationships of gene similarity are most simply explained by the evolutionary descent of these species from a common ancestor.
Barry Greenwald, Harding High School, St. Paul, MN
Can you determine someone's iq by their DNA?
     Kris Wetterstrand, M.S.: No. While undoubtedly someday we will be able to understand the how genes affect certain abilities, things like intelligence are influenced by many factors, including genes, but also envioronment factors, such as education.
What does Mitochondrial DNA do?
     Phyllis Frosst, Ph.D.: Human mitochondrial DNA consists of 5-10 rings of DNA, encoding about 37 genes which generate the proteins involved in cellular respiration. Interestingly, many proteins found in the mitochondria are encoded by nuclear DNA, having been transfered from the mitochondria DNA during evolution. Mitochondrial DNA is frequently used for forensic analysis in samples in which the nuclear DNA has been degraded, it's a bit more stable.
Ben Tolkin, Newton MA
If cow B is a clone of cow A and they bred with the same bull would their offspring's DNA be identical? Would all the offspring look alike?
     Carla Easter, Ph.D.: Wow! Fascinating question. We cannot control for how the genes may rearrange. I would venture to say that the chances are pretty good that the offspring from Cow A and Cow B would be no more identical then the offspring of female twins who happen to have children by the same male.
Erin, Edna High School
Dr. Guttmacher, Are there any new advances in the research and/or use of shRNA?
     Alan Guttmacher, M.D.: Hello, Baltimore, the greatest city in the world (yes, I was born and raised in Baltimore) - SiRNAs are an area of a lot of fast moving and important research these days. Especially, for something that was not even known only a few years ago, it is a tool that promises to have increasing importance both in better understanding the genome and how it works and in translating genome knowledge into applications to health.
Franny and Alex Baltimore, MD
Is there any place to find the Human Genome or pieces of it online?
     Phyllis Frosst, Ph.D.: Absolutely. One of the founding prinicples of the Human Genome Project is that all the information would be immediately available to the public. You can view and analyze the genome at
Ben Tolkin, Newton MA
If being short runs in a persons family, is there a chance that there will be a tall person?
     Kris Wetterstrand, M.S.: Yes, there is a chance. Height is affected by many different genetic elements and since a child can inherit a number of combinations of genes from mother and father, it is possible that the "uncommon" trait can be expressed. Also, environment (like diet) is a BIG factor in influencing height.
Lymiracle Hill, Delaware
To what degree do genes affect our behavior? Is there any explanation of why some identical twins behave more alike than others?
     Kim Kaphingst, Sc.D.: People's behavior is affected by many factors, only some of which are genetic. Behaviors are also affected by the physical and social environment in which people live their lives. So, even people with the same genes might behave differently.
Elisa Chen, Wootton HS
What is the most fascinating part of your job, and were you always fascinated in science?
     Vence Bonham, J.D.: The most fascinating part of my job is the diversity of things that I do. No two days are the same. It provides me an opportunity to work with some of the greatest scientists of our time. I have integrated my interest in science policy, health and education.
Ki A. Santa Monica
Can heart disease be passed down to a younger sibling?
     Ashley Weedn, M.D.: If an older sibling has a heart defect, then yes, a younger sibling is at an increased risk for being born with heart problems. If the parents have heart disease, then that increases the risk for the children to have heart disease - however genetics is just one factor. Behaviors also play a role - eating healthy and exercising are important components of preventing heart disease.
Shivan Friesen, Santa Maria, CA
what happens to DNA when you die?
     Alan Guttmacher, M.D.: The DNA actually remains after you. DNA is simply a bunch of chemicals that are part of cells, so once one dies, the DNA remains in the cells for a long time - depending upon how the body is preserved, potentialy for thousands of years. There are a number of ways that bodies have been identified through analysis of the DNA they contain, in fact.
cha boy B from Westview
What is the current status of gene therapy... Is it being used for human patients right now? What are some of the obstacles that have been solved for this therapy?
     Phyllis Frosst, Ph.D.: Gene therapy is ongoing in research labs and in clinical trials. You can take a look at the American Society for Gene Therapy at for news and links. Some of the biggest recent obstacles have creating vectors that don't evoke a strong immune response, viruses that target to specific cells, but not others, and trying to understand how small animal models really mimic the human response. A lot of the really interesting current clinical trials involve therapies for cancer.
Alexa, Kamiak High School, Mukilteo WA
why does every cell carry dna?
     Kris Wetterstrand, M.S.: Since DNA carries all the information needed to direct cells to do what they need to do (form a muscle, digest food, etc.), it is important that all cells have those instructions. Included in those instructions are the commands to make cells do different things. Certain genes are turned off or on, depending on what the cell needs to do.
What do you see as the major long term goal of genetic research?
     Alan Guttmacher, M.D.: That one is easy - at least to me. Improving human health!
is dna pretty?
     Kim Kaphingst, Sc.D.: Many scientists think DNA is elegant, and even pretty, because such a relatively simple molecule contains the entire code needed to make a living being.
courtney michigan
How does genetics cause depression?
     Teri Manolio, M.D., Ph.D.: We know that depression seems to run in families, but we don't know for sure yet that there are genes that cause depression. If there are such genes, and many scientists believe there are, they probably act by changing the balance of chemicals in the brain that control how signals are sent and received to nerves and other organs. Some of these chemicals are released when we're afraid, for example, and have to prepared to fight or run away. Many people with depression have low levels of chemicals related to happiness or excitement. Genes affect the levels of many of these chemicals, and may give clues as to how depression develops and how it can be treated.
Brittney Herman, Tennessee
When an accident occurs and your body cannot be identified by appearance so that DNA is used, what DNA source is this matched with?
     Les Biesecker, M.D.: There are two ways to do this. The first is to match the DNA to other known sources of that person's DNA. These include toothbrushes, hairbrushes, blood spots from their newborn screening card, bone marrow donor banks, etc. This is called a direct match. The second way to do it is to collect DNA from their close relatives and see if the DNA from the body partially matches the DNA from potential family members. This is called kinship matches. This process is further explained at:
walton philadelphia, Mississippi
will polution have a mutating effect on the human body in years to come
     Kris Wetterstrand, M.S.: It is possible. Certain toxins can affect DNA.
my name is justin and im from washington dc
what prompted the human genome project?
     Belen Hurle, Ph.D.: In the beginning it sounded like a crazy idea because the time commitment and the resources needed were enormous. It was a very controversial idea and many opposed it, with arguments such as it was too expensive, and there was no point in sequencing all the "junk" DNA. Enthusiasts were conviced that technology would emerge along the way that would make it possible, and that we would find more and more uses for the sequence as it would became avalable. They were right!
Nicholas J Salameh the IV, San Diego
What tests can be run to determine if someone has a genetic disorder?
     Alan Guttmacher, M.D.: Erica - It all depends what genetic disorder one is looking for. For instance, sometimes you look at the person's DNA to look for specific mutations, sometimes you can simply use a physical examination to decide whether someone has a genetic disorder. In other situations, other methods are used.
Erica Eddyville Kentucky
Are the people answering these questions just sitting in front of computers waiting to be asked stuff? If so, what sort of shifts are going on?
     Sarah Harding, M.P.H.: Yes, we are all in a big room with lots of laptop computers. But we haven't had to wait too long for questions to come in, we've had a wonderful stream of questions all day long. We originally asked our experts to stay and answer questions for about an hour, but many of them have hung around for much longer to continue answering questions because there have been so many good ones!
David, Albuquerque Academy, New Mexico
If there is a mutation in DNA, can the mutation be removed without damaging the rest of the DNA sample?
     Phyllis Frosst, Ph.D.: At the current time, we are not able to remove damaged pieces of DNA in people. Technology exists to do this in smaller pieces of DNA in the lab for example in bacteria or in yeast, or for generating genetically altered mice for researching disease states.
Robyn and Barbara
When you are a cytogeneticist, what is the most interesting thing you get to do?
     Kris Wetterstrand, M.S.: Cytogeneticists look at chromosomes (of which we have 23 pairs and are the structures that DNA takes during certain steps of the ceel cycle) for adnormalities. This can be very important in diagnosing genetic diseases caused by extra or missing chromosomes or parts of chromosomes.
Ariel Lee, Los Angeles
What is being done to further improve and reduce the ethical, legal and social implications since the start of the human genome project?
     Kim Kaphingst, Sc.D.: One of the unique aspects of the human genome project has been the effort to study the ethical, legal and social implications (ELSI) from the beginning. Here at NHGRI we were concerned about ELSI from the start of the human genome project and set aside 5% of our funding for study of these issues. Many past and present research studies and policy efforts are working toward understanding these implications and ensuring that the benefits of the human genome project to society are maximized.
Shivani, Uni of Leicester, UK
how and why dose a gene turn on and it triggered by the person or is it something that the gene does on its own
     Belen Hurle, Ph.D.: Great question. Genes come with switches that specify when or where the gene is activated. Switches are short DNA sequences (6 to 10 letters) that can be nearby or very far away from the gene. Special proteins named transcription factors bind to the switches and activate or silence the gene as needed.
Keyona, from Upper Marlboro, MD
Do you have to test out many methods before you find out a cure? How long does it usually take?
     Alan Guttmacher, M.D.: it varies widely - sometimes beacuse of good luck or an inelligent approach (often a combination of both), you find a cure very quickly. More frequently, it is a long road ,filled with a lot of minor steps forward before you find a cure - but usually an interesting road.
Kaitlin, Westview Highschool
How would you discover if someone had SCIDS without killing them and how would you treat the disease?
     Les Biesecker, M.D.: SCID or Severe Combined ImmunoDeficiency can be diagnosed by clinical blood cell function testing or by DNA diagnosis. It can be treated symptomatically by isolating patients from sources of infections and using antibiotics, by transplanting bone marrow (blood cells) from an unaffected person into an affected person, and in rare cases, by gene therapy.
Ben Tolkin, Newton MA
Are there any museums where you can go to learn more about DNA?
     Sarah Harding, M.P.H.: Yes! There are many museums that have exhibits on DNA. A great one is the Koshland Science Museum your backyard in Washington DC. They have a wonderful exhibit on genetics, and a brand new webquest on their website about DNA. They can be found online at
Bessie in Washington DC
where does the gene come from in deciding if the sex of the baby? And does DNA matter in deciding what the sex of the child would be, like if there are alot of males in your family, do you have higher chances in having a male child then a female baby, or are the odds always 50/50
     Phyllis Frosst, Ph.D.: In fact, the odds are 51 (boys):49 (girls). The presence of a Y chromosome determines whether the fetus will develop as male or female. We all certainly know families that have many more boys or girls, it's not well understood why this happens, however the thought is that there is most likely a genetic component involved.
Is sickle cell very painful? Is it passed on to other family meambers?
     Teri Manolio, M.D., Ph.D.: Yes, sickle cell disease can be very painful, especially during periods called "crises," when sickled blood cells clump in organs like the sokeebm lungs, and bones. These crises can be caused by minor things such as colds or flu, bumps and bruises, or going to mountains or on airplanes where the air is thin. Sickle cell disease can only be passed from parents to children, not between brothers and sisters or cousins. The sickle cell gene has to be present in both parents to produce the disease in their child. Many people with sickle cell disease do not have children so it is rare for someone with the disease to actually pass it on to someone else.
laura Benitez NorthWestern HS
Are both type 1 and type 2 diabetes hereditary?
     Ashley Weedn, M.D.: Genetics play a role in both types of diabetes - but other factors also contribute to the development of the conditions. For example, risk factors for type 2 diabetes include not only family history but also lifestyle factors, such as a person's diet and their activity level.
Lucinda Yu Carver High School-Houston, Texas
How does genes know that they are dominant or recessive?
     Carla Easter, Ph.D.: The genes do not know if they are dominant or recessive. When we think of a gene being recessive or dominant we are really referring to the expression of the alleles or the variant forms of a gene at a particular locus, or location, on a chromosome. Different alleles produce variation in inherited characteristics such as hair color or blood type. In an individual, one form of the allele (the dominant one) may be expressed more than another form (the recessive one).
Wenyuan Bao, Palms Midle School
Do other mammals have the same principles behind their genetic make up?
     Phyllis Frosst, Ph.D.: Absolutely. All living creatures contain DNA and use it in the same way as we do. In fact, the function of a single cell is pretty consistent among all organisms. And it's not only mammals - insects, plants, bacteria, and even Sponge Bob all have DNA.
How do you cure sickle cell disease
     Vence Bonham, J.D.: Today we do not have a cure for sickle cell disease. There is one variant in the hemoglobin, beta gene HBB that causes the disease. There are many scientists that are doing research including gene therapy and developing new drug therapies to improve the lives of individuals with the disease.
In what grade do you think it is appropriate for students to receive instruction on molecular biology in their science classes? I first learned about DNA technologies in grade 9, but they have recently instituted a biotechnology unit into the 7th grade science curriculum in the middle school I went to. I was surprised by this.
     Alan Guttmacher, M.D.: Tessa - Ths is something that I was jst discussing with a colleague a couple of hours ago. We are surprised even by your own experience - since when we were students we did not learn about DNA technologies until advanced college courses, or even later. The more we learn, the more important this kind of information becomes, so the earlier it makes sense to introduce it into the curriculum. Who knows, some day maybe kids in nursery school will be extracting DNA...
Tessa Carducci Wootton High School Rockville, MD
What first interested you into this field?
     Kim Kaphingst, Sc.D.: I study how to communicate genetic information to members of the public who don't have specialized training in the area. I became interested in this research area because to me this is a really important part of making sure the advances of the human genome project can improve public health. I would like for us to be able to inform people about their genetic risk for disease outcomes in ways that help them use this information to improve their health.
Leslie A, from Mukilteo, WA
Is handwriting hereditary?
     Alan Guttmacher, M.D.: Undoubtedly there must be genes (thus far unidentified) that play a small role in determining handwriting, but I suspect that most of what determines handwriting is not genetic. Of course, one's handwriting might resemble that of other members of the family, simply because having seen it, one consciously or unconsciously copies it, or because family members helped teach you to write.
Rahul Bhatia
Do you think one day we will be able to genetically engineer new creatures through DNA?
     Kris Wetterstrand, M.S.: We actually already do. For years, scientists have genetically manipulated organisms, such as bacteria, yeast, mice and fruitflies, for use in research. If you think about it, humans have been genetically changing creatures for thousands of years through breeding - dogs, farm animals, crops...
Trevor B.
What does RNAi do?
     Phyllis Frosst, Ph.D.: RNA interference (RNAi) is a mechanism in molecular biology where the presence of certain fragments of double-stranded RNA (dsRNA) interferes with the expression of a particular gene which shares a homologous sequence with the dsRNA. Before RNAi was well characterized, it was called by other names, including post transcriptional gene silencing and transgene silencing. Interestingly, RNAi researchers have managed to use RNAi to silence the expression of the HIV virus in mice. Clinical trials performed on human HIV patients began the fall of 2005.
Ben Tolkin, Newton MA
Is there DNA in the food we eat? And if so, what happens to it in our bodies?
     Kris Wetterstrand, M.S.: Yes - there is a lot! DNA is in all living things - plants and animals. We digest it.
Dixon, Westview
What would happen if a gene was damaged, taken out, or turned off permanently while a person is in perfect health?
     Alan Guttmacher, M.D.: Anissa - It depends upon many factors - the specific gene involved, non-genetic factors like diet and environmental exposures, etc. The effect could be anything from nothing to severe problems.
Anissa, Ernie Pyle MS, Albuquerque, NM
If you were to take every piece of DNA in the Human body and stretch them out to their full length and connect them end to end about how many times do you think it would wrap around the earth, or would it wrap around the earth at all? This is to say that if this was possible.
     Belen Hurle, Ph.D.: The total length of DNA present in one adult human is calculated by the multiplication of length of 1 bp x number of bp per cell x number of cells in the body (0.34 x 10-9 m)(6 x 109)(1013) 2.0 x 1013 meters That is the equivalent of nearly 70 trips from the earth to the sun and back! pretty long stuff, isn't it?
Jessie, Michigan
do you think that in the near future DNA can be mechanically made and changed by human beings?
     Kris Wetterstrand, M.S.: We can make DNA now. We can make it from scratch by putting together individial nucleotides. We can also use other research tools, such as artificial bacterial systems, to put together and manipulate streches of DNA.
john hatzis worchester MA
Can genetics help determine an offspring's primary spoken language, or is a child's primary language only learned by hearing it spoken by others?
     Kim Kaphingst, Sc.D.: Studies in early childhood education have examined how children acquire language, and it is thought to be through learning by hearing others. It is possible that genetics might affect learning in some ways, but this needs to be studied further to see how people's genes and their environment affect these processes.
Matthew Rojas, Carver Magnet High School
Do cancer cells divide the same as normal body cells?
     Alan Guttmacher, M.D.: That depends upon the specific cancer cell. Many divide like any cell, but simply do not die like most cells. Others divide at an abnormally rapid rate. Stil others divide in away that the daughter cells contain mutations, or mistakes, in their DNA.
Is DNA present in bodies even after someone dies?
     Kris Wetterstrand, M.S.: Yes. DNA does degrade over time and is influenced by the environment it is in, but it can stay around for a long time. For example, there is a project to analyze the DNA of a mammoth, a long extinct animal.
stephanie mcdonnell
What type of mutation occurs with ALS?
     Teri Manolio, M.D., Ph.D.: ALS, or amyotrophic lateral sclerosis, is caused by a number of possible mutations in the SOD1, or superoxide dismutase 1, gene. The enzyme produced by this gene removes poisonous superoxide radicals produced by the cell by converting them into non-harmful substances. If these poisonous wastes are not removed, they attack cells from the inside, causing their death. More information on this gene can be found at: and at:
Emily Madison Memorial
Is the extreme danger of Avian Flu when it jumps the species threshold specifically related to specific DNA feature(s)? Is there a possible clue to HIV origins also?
     Phyllis Frosst, Ph.D.: The ability of Flu to jump species is releated to its surface and cell binding proteins which are encoded by its DNA. The high mutation rates of viruses ensure that they have lots of genetic changes, some of which enable the virus to infect new hosts. DNA analysis of HIV has revelealed the virus' original host was a chimpanzee as well as many clues to its spread accross the globe.
Deborah, Edna HS
Do you think that sooner or later you can alter DNA to change a trait during someones life?
     Kris Wetterstrand, M.S.: People are already trying to change some genetic conditions through gene therapy, where a properly functioning DNA is actually given to a patient. This type of therapy is still in the early stages of development.
James DeCastro, Westview
Do our behavior and our intelligence reflect what kind of genes are passed on to us?
     Kim Kaphingst, Sc.D.: Human behaviors are complicated and generally due to a number of factors, some of which we know and others we don't. Some of these factors are genetic, while others are factors in people's environments. This is an active area of research.
Eve, Michigan
What type of influence does one's environment have on gene expression patterns in the first year of life?
     Phyllis Frosst, Ph.D.: Researchers are just beginning to understand the effects of environment on gene expression. Certainly what happens to babies in their first year sets the stage for their further development. For example, take a look at this study on baby mice's diet affefcting their fur color:
Eric Madison Memorial
How has the release of information into the general public on the research projects regarding "designer babies" effected the people's initial reaction towards genetic engineering?
     Alan Guttmacher, M.D.: Most projects involving "designer babies" are not research, since there is little research in this area at present. However, there have been a lot of articles in the popular press, shows on TV, etc. about this. I think that these have had different impact upon different people. Some seem to welcome the ability to "enginer" their offspring (even though that reality is much exagerated, often), while others think this is something that humanty should never try to do.
Kassandra, Maryland
How often do you spend time at your lab? If it is a lab.
     Carla Easter, Ph.D.: I no longer work in the lab. But when I did work in a lab, I worked several hours a day (between 8 and 12). I now work in the Educational and Community Involvemenmt Branch and spend about the same amount of time in my office.
Lindsey Marie, john hanson,MD
Is it true that research is being done to enable parents to choose how particular genes will be expressed in their children, for example, height, eye color, hair texture and skin complextion?
     Teri Manolio, M.D., Ph.D.: Serious scientists are not doing this kind of research, but it is possible that someone might someday try to use scientific results in this way. This is much more like science fiction than science, though. If it is ever possible at all, it will probably be much more dangerous, and certainly more expensive, for parents to try to change these traits than to have their children naturally.
Julian, Birmingham, AL
Can you explain the evolutionary theory through genetics?
     Phyllis Frosst, Ph.D.: Bob is a caveman. His genes encode for very early onset cataracts, and Bob has very very poor eyesight. One day, Bob goes for a walk, and doesn't notice a very large, hungry Tyrannosaurus Rex nearby. Bob is eaten by the T. Rex, and his genes are removed from the gene pool. Gradually, people evolve to have fewer genes that predispose to early cataracts.
Robert, Dunstable
How are you celebrating DNA day? Are you having a fancy dinner party?
     Kim Kaphingst, Sc.D.: No fancy dinner party, unfortunately. The best celebration of DNA Day for me is the chance to participate in this chat room.
Emily and Ben Madison Memorial
Are there any different types of cloning?
     Belen Hurle, Ph.D.: There is a difference between reproductive cloning and therapeutic cloning. Therapeutic cloning is an attempt to clone tissues or organs that are a precise match with the patients organs. Reproductive cloning would be to clone whole organisms (identical clones). Dolly the sheep was an example of the later.
sandy peejay
Though the Genome Project tells the sequence of letters in the genome, it does not tell what they do. How helpful would a "second genome project" telling what each gene creates and influences be? Are any scientists
     Kris Wetterstrand, M.S.: The Genome Project did tell us what some of the genes are. Scientists can identify patterns in the DNA that indicate where a gene is. More importantly, there are a LOT of scientists now working to figure out what products the genes make and how the genes are regulated. We fund one such project, ENCODE (see There have been many other genome projects in other organisms (mouse, rat, cow, dog, chimp, the list goes on and on). Each of these projects also tells us about genes in humans.
Ben Tolkin, Newton MA
How does genetic counseling help people?
     Teri Manolio, M.D., Ph.D.: Genetic counseling is used to help people decide whether to get a genetic test and how to use the results. It helps them understand the potential risks to them and their families (if there are any) of a genetic test, as well as the potential benefits. It also gives them a knowledgeable and experienced person with whom to discuss these important issues.
Hannah Los Angeles
As leaders of your respective fields, I would like to know what excites or interests you as far as the cutting edge of genetic research, and what can we expect to see in the coming years?
     Alan Guttmacher, M.D.: One of the great things about genetics today is that there are so many areas in which it is realistic to be excited. Among the most excting to me are the many areas of "translational research" - translating our knowledge of genetics into improving human health. We can expect in the next few years to identify the genes that play a role in many, many common diseases and to craft new prevention and therapeutic strategies based on them.
What is a good way to get college students excited about genetics and help them take a more active interest in science?
     Phyllis Frosst, Ph.D.: It's always a great idea to talk about how genetics will affect their lives, rather than how genetics will affect their exam scores. For some great resources, see .
Roxy St. Ignatius College Prep
Do you have any DNA testing kits that are available to the public that you would recommend?
     Phyllis Frosst, Ph.D.: Here's a very cool looking one from Amazon:
Mark, DC
Will we one day be able to alter DNA before birth to produce cetain traits in a child?
     Alan Guttmacher, M.D.: Technologically, yes. Whether it would be wise to do so is a lot more complicated, however. Many feel it would be appropriate to alter the DNA to prevent disease but not to produce other traits. However, other people feel that even that is not appropriate, while still others think any kind of DNA manipulation would be fine. Your generation will have to help decide these issues!
travis bone, edna high school
Could the DNA in one type of your body's cells be used as DNA in another, different type of cell as DNA?
     Phyllis Frosst, Ph.D.: Well, the DNA in every cell in your body (with few exceptions) is the same. It's the way it's regulated and expressed that's different in every cell. In certain kinds of cloning (for example CC the cat and Snuppy the dog) the nucleus of an egg is removed, and diferent nucleus is introduced. About as close as we get right now.
Adam D. from Florida
Are there left and right DNA helices? we talk about different forms of other molecules, so why not DNA?
     Kris Wetterstrand, M.S.: Yes, there are both. Most of the time DNA is in the right-handed form (B-DNA). The left-handed form (Z-DNA) occurs only under certain conditions, like high levels of salt.
Bob, Tampa Bay
Would it be possible to "turn on" previously inactive genes in specialized cells (i.e. muscle cells) to act like other cells (i.e. nerve cells) to regenerate nerves rather than using stem cells?
     Belen Hurle, Ph.D.: That would be great, but so far we can only reprogram stems cells. Cells that are terminaly differentiated don't respond to our efforts to bring them back to a less differentiated stage. Some organisms show more plasticity than humans. For instance salamanders can regenerate a whole limb after amputation! Perhaps by studying the genome and biology of such organisms, we will learn new tricks.
Evan, Sudbury Ont.
How close is a humans DNA to a lion's?
     Carla Easter, Ph.D.: We have not yet sequenced the lion genome so I cannot give you an exact figure. To date, dogs are the closest sequenced species to lions. The dog genome is about 85% similar to humans. Deductively, lions are probably around 85% similar to humans.
Kathryn, Lyon County Kentucky
Has there been much research into genetic influences on sexual orientation and has it produced any significant results?
     Phyllis Frosst, Ph.D.: There has been, and some interesting hypotheses have been published and in some cases disproven. What's clear is that this is controlled my many genes and in some cases environmental factors. It's been shown a male child with an older male sibling is more likely to be gay. Scientists think it may have something to do with the mother generating an immune response to molecules like testosterone.
Betty, Albuquerque, New Mexico
Promoters are important in the human genome, but they are poorly understood. What is the best way to study promoters?
     Kris Wetterstrand, M.S.: One way to study promoters is to change (mutate) them in a model system (organism used in research) and see how the function of the gene is affected.
Fabian Tobar- Universidad del Cauca-Popay?n Colombia
In your opinion, why is the U.S. falling behind many other countries in terms of science and math education? What will be some consequences and what would you propose we (as educators) do about it?
     Vence Bonham, J.D.: I think there are many reasons why the U.S. is not testing as well as other countries in science and math. Insufficient resources have been dedicated to inspiring students about math and science, or providing the learning environment needed to teach these complex subjects. One consequence is that we may not be able to compete with other countries. I would propose that educators continue to prepare and excite students to pursue careers in math and science.
John Fitz, Wootton High School, Rockville, MD
How is depression considered a genetic disorder, and how would it be passed on?
     Ashley Weedn, M.D.: Depression is actually a multifactorial condition - that is, it appears to be influenced by multiple genes interacting with one another and with the environment. Determing the genetics of depression is complicated by the fact that the complex interactions between genes and the environment are not currently understood. Once these factors are better understood, then inheritance can better be dicephered - allowing us to know which individuals are at increased risk and may develop this condition.
Kassandra, Maryland
What new breakthroughs have there been using RNA interference?
     Phyllis Frosst, Ph.D.: There's some very interesting research into using RNAi to treat AIDS and HIV.
IA, Chicago
Do you think in the future we will find the cure for cancer?
     Alan Guttmacher, M.D.: That would be great, but "cancer" is actually a large family of many diseases, and it is extremely unlikely that any single approach will cure all of them. I think it is realistic to think that in a decade we wil have much better treatments for many cancers, and true cures for more than we do today. However, I think that cancer wil still occur for many years, although less and less frequently, and with better and better treatments for most forms of it.
Dave, Hodgson Vo-Tech
What field of genetics is the most loaded with ethical dilemmas?
     Kim Kaphingst, Sc.D.: That's an interesting question. A number of areas of human genetics have associated ethical questions. Some of the ethical areas that researchers examine are the potential for discrimination based on genetic results and how to ensure that people give informed consent to participate in genetic research. We examine these questions in order to maximize the potential benefits of the human genome project.
Roxy St. Ignatius College Prep
What makes your cell age?
     Kris Wetterstrand, M.S.: The accumulation of genetic changes (damage to DNA) over time or the loss of the ability to divide.
Mr. Mariani
I heard recently on NPR about a gentleman who is working on or has completed an inexpensive way to map a persons DNA - costing approximately 1,000 dollars, you could have your DNA mapped and carry it around in your wallet. His opinion was that it could help people in medical emergencies in doctors office etc. Is this realistic and if it is, how beneficial to the average person would this be? Much thanks, keep up the good work!
     Teri Manolio, M.D., Ph.D.: There are many scientists working on ways to measure every one of the 3 billion DNA letters that make up a person's DNA, at a cost of about $1,000. Such methods, when they're developed, will provide valuable research tools to help us understand what genes do and how they relate to health and disease. But it will take many more years of research and development before we will be able to use such extensive information in an emergency or in a doctor's office. And it will probably still be too expensive for the average patient to have their entire DNA sequence measured for a very long time. The techniques being developed by the gentleman you refer to, and by others, will also be very important in helping us measure a few critical DNA changes quickly and inexpensively. This could soon be done as quickly and easily as we take an x-ray or a blood test in a hospital. We expect that those tests will be very beneficial in everyone's health care.
Jenn, Pasadena, Maryland
Could you please tell the students a little bit about what makes you passionate about genetics?
     Alan Guttmacher, M.D.: Most of all, the ability to improve health. Also, the simple delight of learning new things all the time (I hate to be bored) and even the occasional opportunity to be the first person in the history of the world to discover something and then have the opportunity (responsibility) to share that knowledge with others and see them expand upon your own discovery.
McGrid, M.D.
How did genes that have similar functions end up being grouped together in closely related DNA sequences known as operons? Why aren't genes, regardless of function, located randomly throughout the DNA sequence?
     Phyllis Frosst, Ph.D.: Operons are not only genes with related functions that are close together on chromosomes, but they also share common regulatory and control regions. It is thought that it might be an evolutionary advantage to have this kind of transcriptional efficiency.
Bert - Washington
From learning genetic engineering, is it possible to increase a person's life span? If so, how?
     Carla Easter, Ph.D.: With human genome project data, researchers are trying to discover the genes involved in aging. Some day, we may be able to extend a person's life using gene therapy or genetic engineering. Right now, we are not at that point.
Andy Brooklyn
Can drugs mess up your DNA?
     Kris Wetterstrand, M.S.: Yes. It is possible for drugs to directly damage DNA.
David Price
What is the double helix?
     Alan Guttmacher, M.D.: The double helix is the structure of DNA, first discovered by Watson and Crick (building upon the work of others, as is almost always the case in science) and published 53 years ago today!
cheray richardson
Are there any genetic disorders that are not harmful and will not cause a decrease in life expectancy?
     Phyllis Frosst, Ph.D.: It all depends on how you define a genetic disorder. Things like colorblindness are kind of disorders, but they're not particularly harmful. Also, some disorders have advantages too. For example Sickle Cell Disease is thought to offer the host resistance to malaria.
Kim, DE
What is the explanation for the long repetitive sequences in the genome?
     Belen Hurle, Ph.D.: I am not sure if you are talking about microsatellites or about repetitive elements. I will comment on microsatellites. When the DNA polymerase encounters a repetitive sequence, let's say a stretch of CACACACA bases, it is relatively easy to make a mistake and introduce several CACA more than there were in the original sequence. With time, different individuals will end up with stretches of CACA that have different lengths at the same position. We call them microsatellities and they are very useful in forensic science to create a genetic profile of a person.
A. Williams
Are there ways of changing an organisms DNA makeup?
     Phyllis Frosst, Ph.D.: Definitely. It's relatively easy with bacteria and yeast, and a little harder with us. In humans, the technique is called gene therapy.
Veronica Vasquez, DC
Why is DNA Day on April 25?
     Kim Kaphingst, Sc.D.: There are two reasons DNA Day is April 25. First, the double-helix structure of DNA was described April 25, 1953 by James Watson and Francis Crick. In addition, in April 2003, the International Human Genome Sequencing Consortium placed the essentially completed sequence of the human genome in public databases.
Julija,Garfield, NJ
Why is DNA twisted?
     Kris Wetterstrand, M.S.: It has to do with the way that the individual chemicals(nucleotides) bond to each other.
Steve Kaminski, Stow Munroe Fallss H.S.
When will doctors use DNA testing to determine common risk factors like heart disease or stroke?
     Alan Guttmacher, M.D.: A great question. Doctors are already using DNA testing occasionally to determine a specific individual's risk for heart disease, stroke or other common diseases. However, for most patients, this is stil not a practical approach. It will become gradually more and more practical - my guess is that it will be part of the standard care for most people in another decade or two.
charles fittz, Groton Dunstable High School
When is the right time to use the results from DNA testing?
     Teri Manolio, M.D., Ph.D.: It depends on the test and why it's being done. For a test done to determine if someone has a gene causing a particular disease or symptom, for example, the right time would be as soon as the result is received and the doctor and patient have agreed on the right course of treatment.
Olivia M.-BRMS Bradenton, FL
How do proteins created by the gennes in your nerve/brain cells translate into thoughts and emotions? Also, why doesn't a patient's immune system destroy a vector that sends genes in gene therapy?
     Phyllis Frosst, Ph.D.: Your genes encode all the proteins and instructions to create your brain and your nervous system. These underly our ability to think and feel. To answer your second question, frequently the immune system does attack the viruses used for gene threapy. Scientists work hard to change gene therapy virus vectors so that they're no longer recognized by the immune system, causing an immune reaction and destroying the vector.
Ben Tolkin, Newton MA
What kind of technology was developed during and for research on the human genome project?
     Kris Wetterstrand, M.S.: The Human Genome Project was the first large-scale, high-throughput biology project. It motivated the development of machines and methods to sequence DNA faster, cheaper and more accurately. Faster DNA sequecing machines we developed. New enzymes for manipulating DNA were developed. Computer software was developed to deal with the deluge of sequence data.
LaMonica Carver Houston, texas
How would sequencing the Human Genome be of use to us, and how would it affect our daily lives?
     Alan Guttmacher, M.D.: Sequencing the human genome (achieved three years ago) has already proven extremely important to biomedical research and is beginning to be of importance in understanding much of human health and disease. It will affect our lives by improving our health and making us in more control of our health.
Michael Wu Thomas S. Wootton HS
What is genetic engineering?
     Carla Easter, Ph.D.: Genetic engineering involves the manipulation of an organism's genes. Some of the fields that utilize the techniques of genetic engineering, include agriculture, biology, and biomedicine.
Just like how people dye their hair certain colors, would we be able to change out DNA around to change our hair color?
     Phyllis Frosst, Ph.D.: My sense is that this is way ahead in the future. We're not able to change our DNA to cure disease, I think hair color a little further down the list. But look for a new DNA-clairol product in 20 years or so...
Jessica- Delaware
How often do you see the "weird" DNA?
     Phyllis Frosst, Ph.D.: If you're talking about things like Z DNA, they're pretty rare, and disbursed throughout the genome.
Savannah P'Poole Lyon Co. Middle School, Kentucky
how many animals have been cloned successfully?
     Kris Wetterstrand, M.S.: Tadpoles, sheep, goats, cows, mice, pigs, cats, rabbits, and a gaur. See
Greg, Madrid
Why do viruses evolve faster than humans, even though humans reproduce sexually (promoting evolution) and viruses don't?
     Belen Hurle, Ph.D.: Viruses make thousands of copies of themselves at a very fast speed. Hundreds of random mutations are popping up constantly in the virus population. Those mutations that, by random chance, give the virus an edge, get selected and spread out very fast. Soon the entire population has shifted toward the advantageous version of the virus. It is natural selection at its best!
Ben Tolkin, Newton MA
If genetic mutation is a disorder in the DNA, and genetic engineering is taking a piece of DNA and putting it into a new body; is it possible to take off the piece of DNA where there is a disorder, thus making the DNA fine
     Phyllis Frosst, Ph.D.: Not yet. We can start to do this in mice, where scientists are able to generate models of human disease, be removing chunks of DNA and replacing them with other chunks.
Andy from Brooklyn
What does the word pedigree mean when it comes to pedigree charts?
     Carla Easter, Ph.D.: A pedigree is simplified diagram of a family's genealogy that shows family members' relationships to each other and how a particular trait or disease has been inherited.
Hakeem- Newark DE
It is said when dna replicates there may be a problem, that if a nucleotide ends up with a wrong pair, it forms a denature and may cause cancer. Does that mean you have no chance of ever preventing cancer, if it's all that random?
     Teri Manolio, M.D., Ph.D.: It's true that cancer often comes from random mistakes in copying DNA, but the body has many defense mechanisms to correct those mistakes. Some of those defense mechanisms can be damaged by poisons such as asbestos or cigarette smoking, or even by some viruses. And some of these defenses can be boosted by certain drugs or even by a balanced diet and by certain drugs. We've made great progress in preventing cancers so far, and we're very hopeful that genetic research will enable us to prevent even more in the future.
connor rhodes,california
If you looked at someone's DNA, would it actually look like a staircase?
     Belen Hurle, Ph.D.: yes, it looks like a staircase!
Do you think it is possible to make a virus that will not harm or make a human sick but will transfer good genes to replace bad or mutated genes for gene therapy?
     Phyllis Frosst, Ph.D.: I completely believe this is possible, and very good clinical trials are ongoing right now. For example, gene therapy viruses that target only tumors, and destroy them.
Brittany, Sharon Pa
Is it dangerous for first cousins to marry and have children?
     Alan Guttmacher, M.D.: First cousins do have an increased risk of having a child with an autosmal recssive condition, but since autosomal conditions are rfelatively uncommon, the children of first cousins are not all that much more likely to have health problems than other childre. While there is scientific debate about the precise numbers, it is sometimes said that any child has a 3-5% chance of being born with a birth defect or inherited condition, and the risk for the child of first cousins is eleavted to something like 4-7% - a slight increase, only.
Daniela Ponce, Chile
Is it possible for you to get a genetic disorder (like down syndrome or hemophilia) over time?
     Les Biesecker, M.D.: Most genetic disorders are present at birth but some may be "silent" in children and young adults and may only be detected later in life. But severe diseases such as Down's syndrome, hemophilia, or sickle cell anemia are almost always detected at birth or shortly after, and do not develop over time.
Sarah from LA
Is it true that hair loss is hereditary?
     Ashley Weedn, M.D.: Yes, hair loss can be hereditary. In fact, androgenetic alopecia (alopecia is the medical term for hair loss) is the most common cause of hair loss (due to a genetic sensitivity to androgens). But, there are other causes of hair loss, too, including certain medications and medical conditions - hair loss can even result from severe stress!
Ahmad McCown- Newark,DE
If proteins have specific functions in every facet of DNA and RNA, which came first, DNA or Proteins?
     Phyllis Frosst, Ph.D.: A great question that scientists are still thinking about, see an intersting article here:
John Fitz, Wootton High School, Rockville, MD
How do you think the practice of medicine would be different today without the discovery of DNA?
     Alan Guttmacher, M.D.: The practice of medicine today would not be so different, but if you ask me that question in ten or twenty years, my answer would be very, very different. That is because we are at the dawn of the "genome era" in which we can use new genomics tools to understand much more fully how DNA functions and how it translates into human health and disease - and, even more importantly, use that knowlege to improve health.
Michelle, Westview High
What was the cost of the entire Human Genome project?
     Kris Wetterstrand, M.S.: Sequencing of the human genome cost $300 Million. Often, though, a number of $3 billion is quoted, but that includes years of technology development, sequencing of smaller genomes and mapping (fingerprinting) work on the human genome.
Carlos Ivan Reyna Alberto Houston TX
We learned in class about how human genes can be used in bacteria to make insulin for diabetics. How much more effective is this than the previous methods of obtaining insulin?
     Ashley Weedn, M.D.: It is actually much more effective because it doesn't produce antibodies to beef or pork pancreas tissues that often inactivated insulin derived from these tissues.
I?m a student of biology at University of Cauca, and I study the regularities in the human promoters. What do they know around them?
     Belen Hurle, Ph.D.: Promotors are subject to intense study these days. Promoters determine when and where the gene is expressed. The problem is that it is hard to write and train a computer program to identify those tiny switches. But we are making progress thanks to our ability to compare genomes. The current estimates are that 1.5% of the human genome encodes genes, and 3.5% of the genome encode switches.
I read an article that the Y chromosome is starting to disappear in males, is this true and why?
     Carla Easter, Ph.D.: Yes, throughout evolution the Y chromsome has lost many of its genes. We really do not know why the genes are being lost. For more information see David Page's website at
Rachael Murray, Weview High
To me, 53 years ago doesnt seem that lonng ago. I thought DNA was discovered hundreds of years ago. Why did it take so long for DNA to be discovered?
     Phyllis Frosst, Ph.D.: The idea of inheritance came a long time ago, think Mendel and his peas, and the idea that it was DNA and not proteins responsable, came in the 20s. In 1953, Watson and Crick determined the chemical structure of DNA, an incredible important milestone, but they built on a sturdy foundation.
K. Hurley, New York

Information - Moderator It is 6 pm on the East Coast and the DNA Day Chat Room for 2006 is now closed. The transcript of the entire day's conversation will be available immediately after the Chat Room is closed, including the announcement of the winners of the essay contest. Thank you for participating in this conversation and for all of us at the National Human Genome Research Institute, good night and good luck. See you next year.

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Posted: April 25, 2006