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2006 National DNA Day Online Chatroom TranscriptThe 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.
Q: St. Ignatius College Prep High School: What kind of new and exciting applications do you hope for in the field of medical genetics in the near future? A: 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. Q: Koshland DNA Day participant: If you had billions of dollars for your research what (in your research) will you spend it on? A: 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 genome.gov. 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. Q: Koshland DNA Day participant: Can genetics tell us exactly how infants will react in life? A: 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. Q: St. Ignatius College Prep High School: 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? A: 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".
Q: Zac Trupp-Wootton High School: How much of the genome do we have specific function information for? A: 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... Q: : Two related questions came in at about the same time: "Can we eat DNA?" And "What does DNA task like?" A: 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?). Q: St. Ignatius College Prep High School: Should American doctors be under pressure to "encourage" all mothers-to-be to do prenatal screening as part of normal prenatal care? A: 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. Q: : Are you currently accepting internships? A: 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 http://www.training.nih.gov/. Q: Ben Plotsky, Thomas S. Wootton High School: 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? A: 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. Q: Janell Holloway: Banneker AHS: 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? A: 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. Q: Jennifer, Maryland: DNA Day Finally here!!! DNA Day CHEER, CHEER, CHEER!!! DNA Day Really Rocks!!! GOOOO Double Helix!!! A: Sarah Harding, M.P.H.: Thanks Jennifer! We're excited to be here too! Q: Tessa Carducci Wootton High School: 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? A: 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. Q: Kris Ferguson, Greenville, Alabama: What is the rarest type of disease that has a genetic basis? A: 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 www.progeriaresearch.org or www.genome.gov and search for Progeria. Q: Shivani, Uni of Leicester, UK: 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? A: 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? Q: Lina Feng - Wootton High School: 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? A: 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. Q: Shivani, Uni of Leicester, UK: Are gene tests available for complex diseases, diseases which have no cure, or diseases that may have a late onset? A: 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. Q: Josh Lee, TWHS: Could DNA be possibly used in the future to help hire people? A: 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. Q: St. Ignatius College Prep High School: 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? A: 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. Q: Michael Wu - Wootton High School: What has the Human Genome project told us so far, and how does it help is in our daily lives? A: 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. Q: Ben Plotsky, North Potomac, MD: Is there any way to determine whether or not I have a genetic disorder without using karyotyping? A: 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. Q: Koshland DNA Day participant: What advances or cures do you think studying genetics will yield in the next 5-10 years? A: 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. Q: Katie H and Sam S: In the future, will it be possible to change DNA in place of plastic surgery? A: 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! Q: Chris Walka, Marshfield MA: In the future, will parents be able to change the DNA of an embryo so that the child will have certain characteristics? A: 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.
Q: Shivani, Uni of Leicester, UK: What improvements have been made in the ethical, legal and social implications since the start of the human genome project? A: 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. Q: St. Ignatius College Prep High School: 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? A: 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).
Q: St. Ignatius College Prep High School: 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? A: 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. Q: Jenn, Pasadena, Maryland: 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? A: 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 www.genome.gov/16015415 Q: Gerald Holton Licking Heights HS: My students are learning about replication right now is there anything that is new and exciting about DNA replication A: 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. Q: Richard Lui, Newton, MA: Does DNA have a color? A: 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. Q: Zac leuci - hodgson high school: 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? A: 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. Q: St. Ignatius College Prep 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? A: 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. Q: Steve Brown, Marshfield Ma: Can you determine when you will die through DNA? A: 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. Q: Vinay, Thomas Sprigg Wootton High School: 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? A: 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. Q: Sandeep: 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? A: 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. Q: St. Ignatius College Prep High School: 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? A: 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. Q: Nancy Guy: How many bases are there in a Human DNA molecule? A: 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. Q: Amelia E. Wootton HS: 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?" A: 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." Q: Larry Small, Marshfield, MA: What can 10th graders do to get involved in real DNA research? A: 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. Q: Sam T, Wootton HS: What is your favorite DNA base? A: Eric Green, M.D., Ph.D.: G (for Green), although I don't really dislike A, T, or C. Q: St. Ignatius College Prep High School: What is a typical day like for you as a genetics scientist? A: 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. Q: 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? A: 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. Q: St. Ignatius College Prep High School: What institutions, labs, nations should we keep an eye on for further research in gene therapy? A: 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 (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi) 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 www.asgt.org . Q: Koshland DNA Day participant: Do people have different DNA? A: 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. Q: Vu Luong: Banneker AHS: Has anybody ever read the entire human genome project? Who? A: 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. Q: Koshland DNA Day participant: Have scientists finished sequencing the H5n1 virus? A: 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). Q: Koshland DNA Day participant: Where do you feel genetics will go in the next 5-10 years? A: 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.
Q: Shivani, Uni of Leicester, UK: If a child is up for adoption, should his or her genetic information be collected? A: 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.
Q: Read Carney, Newton, MA: What did it feel like to finish mapping out the human genome? A: Eric Green, M.D., Ph.D.: It was way cool! It truly felt like you were part of something of great historic significance. Q: Brian Petty: Banneker AHS: What was the most challenging part of sequencing the Human Genome Project? A: 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. Q: St. Ignatius College Prep High School: 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? A: 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. Q: Haena Cho, Wootton 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? A: 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. Q: Megan Foley, Hazel Park High School: Can the atoms in the DNA molecule actually be seen? A: 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. Q: J Watklevicz New York: Does DNA affect your intelligence? A: 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.
Q: Katie Wilson, T.S. Wootton H.S.: Are there any predictions as to the function of the 95% unknown genome? A: 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 http://www.genome.gov/10005107. Q: Richard, from K-12: Why does Adenine pair with Thymine? A: 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. Q: Tessa Carducci Wootton High School: What are the latest breakthroughs in RNAi technology and what are researchers currently investigating in relation to this topic? A: 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. Q: St. Ignatius College Prep High School: What, in your view, is the most controversial area of genetic research today? A: 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. Q: Shivani, Uni of Leicester, UK: 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? A: 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 http://www.genome.gov/10002077 Q: St. Ignatius College Prep High School: 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? A: 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. Q: 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.? A: 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.
Q: Paul from Pennsylvania: How much has genetic research advanced in the last year? A: 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. Q: andre scarbrough: Why is DNA important? A: 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.
Q: Gabriel Hua - Wootton High School: What is the general procedure for determining disease-causing genes? A: 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. Q: Britney Green,Washington D.C: What is so good about DNA day. A: 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! Q: Alex Newton,MA: Why are the DNA bases named Adenine, Thymine, Cytocine and Guanine? A: 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. Q: Claire, Thomas Wootton High School, Maryland: 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? A: 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. Q: Koshland DNA Day participant: How well are science projects such as the Genome Project a national priority according to the political administration? A: 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. Q: Josh Lee: Is there any correlation between mutations in DNA and being gay? A: 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. Q: Breyona Trent and from upper Marlboro MD: Is your job hard? What makes it that way? A: 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. Q: jamona, Maryland: Why is DNA so important? A: 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. Q: One and Only: Why is DNA required? A: 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. Q: Kristen Afflack: Why do you do this job? A: 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. Q: Grace Hyun, Newton MA: Can you determine through genes how a baby will look and how smart they will be? A: 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. Q: chasity and im from uppermarlboro md: How do you know so much about DNA? A: 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. Q: frederick douglass highschool: what is the purpose of dna day A: 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. Q: Juan Jose, NM: Como Estas? A: 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! Q: Ben Plotsky Wootton High School: Why would you choose a dog to compare the genome? Why not something else, say a three-toed sloth? A: 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. Q: St. Ignatius College Prep 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? A: 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. Q: Dr. Steven Fine, Medical Arts High School, Camden, N.J.: What education is needed to become a genetic counselor? A: 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! Q: Shivani, Uni of Leicester, UK: What in your opinion is the biggest ethical, social and legal implication resulting from the human genome project? A: 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. Q: MICKY: Can drugs alter DNA? A: 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 http://www.nida.nih.gov/ Q: Big Will From Maryland: How did people find out about DNA? A: 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. Q: Matt Vertescher, Newton MA: What is RNA? A: 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. Q: Shivani, Uni of Leicester, UK: Do you think the future could end up as seen on the 1997 film "Gattaca"? A: 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). Q: Steven, Hartford: Is there a cure for Adrenoleukodystrophy? How far are along do you think they are in curing the mutation in the gene? A: 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. Q: Brown Middle School, Newton MA: Why did you decide to start studying DNA, and did you use any helpful equipment? A: 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! Q: Ben Plotsky-Wootton High School: Where is the most research being done into the human genome? A: 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. Q: J Watklevicz New York: Is it possible to identify a certain base sequence that would correspond to a certain trait? A: 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. Q: Steve Brown, Marshfield: Can DNA be used in weapons of mass destruction? A: 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. Q: Maru: Que es hoy el dia de DNA? A: 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! Q: Max Posner Newton MA: How do genes turn on and off? A: 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. Q: Dr. B.B.S.P.Nag, SMV Centre for Biotechnology, NAGPUR, INDIA: How is genetic counseling useful in the case of psoriasis and arthritis? A: 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. Q: D. Percoco, New York: Have any other animals, such as fish, had their genome sequenced? A: 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. Q: St. Ignatius College Prep High School: 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? A: 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. Q: camren: Que es el ADN? A: 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. Q: kasia phillips, co-op city, the bronx: DNA stands for Dinosaur Nose Acrobatics, right? A: 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. Q: Makarai Stone, Upper Marlboro, Maryland: Are human genetics completely understood yet? A: 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! Q: Carmelita: En que paises se celebra este dia? A: 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! Q: Lindsey Couture: What are the current advances in gene therapy for Cystic Fibrosis? A: 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. Q: Delaisa Jackson for Doulass: What makes twins? A: 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. Q: Kayla Morgan: How is DNA related to colorblindness? A: 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. Q: Allison- Everywhere and Nowhere: 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? A: 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. Q: Sarah Holmes Liberty, MO: What is the difference between genetics and genomics? A: 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. Q: Olivia, Italy: How long have you been studying DNA? A: 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? Q: claire godfrey: Will finding out the sequence of human genomes help us to prevent diseases and actually do anything about it relatively soon? A: 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. Q: casey and lisel from Sacred Heart Academy: Where do Attention Deficit Disorder and Attention Deficit Hyperactive Disorder come from? Are these disorders genetic? A: 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. Q: N. Duetsch, New York: Can animals inherit genetic disorders? A: 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. Q: shannon donlo, stanfprd, connecticut, 54 carter drive: Where can you find dna on your body? A: Belen Hurle, Ph.D.: In every single cell, except in red blood cells and eye lens cells. Q: olivia Newton: How do they perform a genetic test? A: 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. Q: sophie and Svetlana from Sicily and the Ukraine: how many chromosomes are in a full DNA? A: 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. Q: Biology B Class, Staples High School: 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. A: 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. Q: Maru, CT: Donde se estudian el DNA? A: 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. Q: Jason newton mass: how do you identify the identity of a person from dna A: 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. Q: otilia, newton: What courses in college do you have to take to have a job like yours? A: 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! Q: mordacai, montana: Who was the first person to finish the human genome and did they win a nobel prize? A: 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. Q: Ryan Guatemala: Is DNA fun??? A: 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. Q: Laura: Hola como estas. Tengo una pergunta para usted. Que es la RNA y es lo mismo que al DNA? A: 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. Q: Kasia Phillips, Co-Op City, Bronx: When was DNA day first started? A: 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. Q: Alex & Mallory, Cape Elizabeth, ME: What is your favorite genetics movie? A: 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! Q: Ben Plotsky Wootton High School: What is the most effective way to determine what a specific part of the genome does? A: 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. Q: Brendon Newton MA: Can people take your DNA and copy it? A: 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. Q: royse upper marlboro md: If parents want their child not to inherit a certain gene, such as one for hair texture or hair color, is that possible? A: 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. Q: Jeffrey Soffer Wootton High School: Can genetics control one's personality? A: 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. Q: pooja tiwari, SMV Centre for biotechnology, Nagpur,India: 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? A: 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. Q: mordacai, montana: Is everything that we see on CSI true? A: 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. Q: Lappi: Can crossing over occur between the X & Y chromosome? A: 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. Q: Josh Jarriel: What is the most common genetic disorder affecting humans today? A: 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%). Q: solomon newton MA: How long will DNA last once you die? A: 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. Q: D. Lawrence, New York: How do homologous chromosomes pair up during meiosis? A: Heidi Parker, Ph.D.: Homologous chromosomes pair based on the similarity of sequence between them. Q: Kayla Morgan: How close is the DNA of a human to the DNA of a peanut? A: 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. Q: Annette: 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? A: 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. Q: James Fortin, Maine: What is your favorite part of your job? When did you decide you want to be a geneticist? A: 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. Q: Matt Nguyen Oakes, South Africa: What does DNA really look like? A: 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! Q: Alexj, Germany: What is a genome? A: 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. Q: Sean, south fork highschool: What is the most important thing I should learn today from this experience. A: 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. Q: Jamie, Crawfordsville, Indiana: Do you think that the human genome project will assist us with environmental pollution concerns? A: 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. Q: Johnny, Crawfordsville, Indiana: What does DNA tell us about the fact that animals have hair all over their bodies and humans do not? A: 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. Q: Maia Stamieszkin from Cape Elizabeth, Maine: What is the relationship between genetic variation and cancer progression? A: 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! Q: Adrienne Liberty, MO: Does having a brother with autistic tendencies and other mental-health related issues put me at a greater risk of having an autistic child? A: 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. Q: Stanis Moody-Roberts, Cape Elizabeth Maine: What other species are most similar to humans in DNA? A: Phyllis Frosst, Ph.D.: We're the most similar to Chimpanzees, at 96% identity. We're the closest to other primates, as well. Q: John Smith From Alaska: Have scientist found a cure or treatment for Klinefelters? A: 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. Q: otilia, newton: What was the most difficult case of DNA dissorders that you ever discovered? A: 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! Q: Emma of Cape Elizabeth, ME: Are there any concerns now about how the gene research will affect our society in the future? A: 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 http://www.genome.gov/10002329. Q: Carrie Liberty, MO: 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? A: 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. Q: Joshua Johnson, Washington DC: Can monkeys get genetic disorders? A: 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. Q: Ort Gay: How big is the average genome? A: 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! Q: Jack Mayof: Who would you say is the most influential genetecist in the history of discoveries? A: Francis S. Collins, M.D., Ph.D.: James Watson and Francis Crick, though Mendel is a close second (or is that a third?) Q: Ryan: How is DNA made? A: 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. Q: Tori, South Fork: If your son or daughter died, couldn't you make a clone of them from their DNA? A: 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. Q: Christine, Newton, MA: If the slight differences in DNA account for the differences in our traits, how do we have a "human genomic standard" for comparison? A: 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. Q: Claire Liberty, MO: Has anyone found DNA on Mars? A: 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. Q: christopher: Do all animals have the same kind of DNA? A: 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. Q: M. Ward - South Fork 14, Kincaid, IL: Why is there still so much debate about whether schizophrenia is a genetic illness? A: 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. Q: Shannon Hudson, Crawfordsville, Indiana: Are their any advances in the study of Fuch's Dystrophy? A: 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. Q: Chris, Crawfordsville, Indiana: What all do we know about the gene that causes diabetes? A: 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. Q: Courtney, Illinois: What does the term Genome mean? A: 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: http://genome.gov/18016863 Q: Kirstie, Illinois: If our genes evolved from monkeys, then why are there still monkeys? A: 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. Q: lewis newton mass: Does grass have DNA? A: 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. Q: Daniela Ponce, Chile: El oxigeno el capaz de danhar DNA? A: 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. Q: pooja tiwari, INDIA: I want to contribute to the genomic biology how can I get an opprtunity to work with people like you? A: Francis S. Collins, M.D., Ph.D.: We need LOTS of smart people to work in the field of genomics. Have a look at genome.gov/CAREERS! Q: mordacai, montana: How long does it take to analyze DNA? A: 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. Q: Dick Bufu, France: What is the most inportant part of a geneticist's job? A: 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. Q: Lappi: Are cysts hereditary? A: 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. Q: Alaina Hahn-Tualatin OR: Can anyone explain what Progeria is??? A: 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. Q: Mark (Sleepy Eye, MN): Was the human genome completed in 2000 or 2003? A: Phyllis Frosst, Ph.D.: A "working draft" of human genome was completed in 2000 and the high quality genome sequence was released in 2003. Q: catie, IL: What is gene imprinting? A: 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. Q: Sade Wilson: What do you like about your job in genetics? A: 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. Q: Zeetie, Arkansas: 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? A: 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.
Q: CeCe, europe: How close is our DNA to a dog's DNA? A: 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. Q: flannery Newton, MA: Whose idea was it to start the Human Genome Project? A: 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. Q: Cicily, South Fork, IL, USA: Is DNA hard to study? A: 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. Q: James pumpernickel-Fortin Puerto Rico: Is there anyway to stop the telomeres from aging in cloning experiments? A: 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. Q: Laura, Newton MA: If a child has cancer, is it because of their parents' genes? A: 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. Q: Adam Friberg, Washington D.C: What effect does alcohol consumption have on your DNA? A: 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. Q: A. Collins, New York: Is it possible to "cut out" a disease/ genetic disorder in a carrier? A: 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...... Q: Madre Interesante: Are the DNA tests on TV acurate? A: 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. Q: Caitlin Masterman -- Wootton High School: 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? A: 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. Q: : What is the genetic disorder that causes Asperger's syndrome? A: 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. Q: Chelsey, Sleepy Eye: do you eat genetically modified food? do you like it? A: 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. Q: Bwwwennndannn like dinosaurs: 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? A: 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. Q: Joshua Johnson, Washington DC: What living organism has the largest genome? A: Heidi Parker, Ph.D.: According to www.genomesize.com 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. Q: Chris Stokes Maryland: What is your favorite thing about the cell? A: 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. Q: Alaina: What would you want to study if you were not a genetic researcher?? A: 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. Q: alex newton. massachusetts: Can two parents who have a genetic disease have a child who does not? A: 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. Q: Alex and I'm from Connecticut: What is the Human Genome Project? A: Alan Guttmacher, M.D.: Hello Alex (Connecticut is a good place to be from - my wife is from Connecticut) - The Human G |
