Skip to main content

2007 National DNA Day Online Chatroom Transcript

The 2007 National DNA Day Moderated Chat was held on Wednesday, April 25th, 2007 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.

  View experts' research areas/focus

TIP: To search ALL years, use the Google search at the very top of our site then select the "Chats" filter on the left.

Do you have to take any special classes to have the job that you have? How long did you have to go to school for this particular job?
     Sarah Harding, M.P.H.: That's a great question. I work in the education branch here at NHGRI and went on after college to get a master's degree in Public Health Genetics. Many of my colleagues have their Ph.D.s in various topics, others have their law degrees or medical degrees, depending on what their interests are.
AudryeRose Gilbert HPMS
My mom's side of the family has heart problems, what is the chance that in the future my family could find out who will have these problems?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: There are many different causes of heart disease, so it depends on the cause of your mother's heart problem. Although genetics plays a major role in much of heart disease, it is not the only factor at play. A person's environment - eating and exercise habits -also play a role. I suggest that you consider genetic counseling to help answer your question. A genetic counselor can help you to gather the necessary family health history information to help you find out whether other family members will develop heart disease.
Could you explain Genetic Discrimination and how it occurs in scientific life?
     Barbara Fuller: Usually we think of genetic discrimination as an action based solely on the results of someone's genetic test, and not on an actual manifestation of disease or condition. I am not sure what you mean by asking how it occurs in scientific life, but it could happen, for instance, in health insurance or employment if decisions are made on what could possibly happen because of a person's genetic test results rather than whether or not they have an illness or condition. Your question is very timely because at this moment the U. S. Congress is considering a bill that would prohibit genetic discrimination.
Bartek Patel, Berlin, Germany
What is the most common nitrogen base in DNA?
     Carla Easter, Ph.D.: It depends on the species and on the region of the genome you are referring to. Even within the human genome, there are regions that are AT-rich and other regions that GC-rich.
Amanda Newton MA
If no one in your family has previously had a heart-attack, are you less likely to have one?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Heart disease can be caused by genetic factors. But, you can still develop heart disease even if it does not run in your family. Lifestyle factors such as diet and exercise also play a major role in your risk for heart disease.
Marshall Mathers - Detroit, MI Holy Family Catholic
Are you able to get a DNA profile from urine?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Theoretically it is possible because there are often cells in a person's urine. However, in clinical settings we usually get DNA from a blood sample or from cells on the inside of the mouth (buccal cells).
Heather,Erie One Boces
Dr. Laric: What types of scientific backgrounds do the people you work with have?
     Pnina Laric, M.S.: Some of the people I work with have studied various scientific disciplines like genetics and biochemistry, while others have studied bioinformatics (the emerging field where biology, statistics and computers intersect to manage and analyze all of the biological data we're generating these days). Still others have studied science education, science policy (this can inform and influence our lawmakers of current advancements in science) or law (for example intellectual property law, which aims to identify who 'owns' the rights to a particular scientific discovery).
Amie, Denver CO
Is Guillain Barre syndrome genetic?
     Gary Temple, M.D.: Guillian Barre syndrome is not inherited as a disease, but some individuals may acquire GBS in part due to a genetic predisposition, meaning that they have inherited genes that make them more susceptible to developing this autoimmune disorder, after some kind of triggering event. Although the triggering event is often not known, in some cases GBS is preceded by a viral or bacterial infection.
Giovanna Zanetti, Oratory Schools, Pharr, TX
There is only 1 percent difference between humans and apes on genomic level then why is there is so much difference at the phenotypic level?
     Vivian Ota Wang, Ph.D.: Isn't it amazing how much phenotypic differences is produced by 0.1% of the genome? What researchers are discovering is how DNA and its products are so complicated in what it does. Combining this with environmental and behavioral factors results in a variety of phenotype differences you see (and don't see).
Rohan Thaware,SMV Centre for Biotechnology,Nagpur India
Is animal DNA more difficut to analyze then human DNA?
     Pnina Laric, M.S.: Sometimes. For example, I know that platypus DNA and dog DNA are really hard to analyze. Who knew?
Will genetic screening affect the way insurance works? And will there be any laws made to prevent discrimination?
     Barbara Fuller: This is a very timely question because at this very moment the U.S. Congress is considering approval of a bill that would prohibit genetic discrimination by insurers. This bill addresses the concern that insurers may discriminate on the basis of an individual's genetic test - not whether they actually have a disease or condition.
CruzMaria Velazquez
Is there a gene in our DNA that shows where we come from? Is there a gene that says I am Puerto Rican or African American?
     Mary Schueler, Ph.D.: Your genes tell the history of your geographical origin in a very broad sense. Your genes are also those of your ancestors. Your chromosomes share regions with your parent's chromosomes and each of your parent's chromosomes share regions with their parent's chromosomes. Regions common among groups of people tell the story of human migration over time.
Leilani Morales, Paterson, Nj
what is a tetrad?
     Carla Easter, Ph.D.: A tetrad is a four-part structure that forms during meiosis and consists of two homologous chromosomes, each is composed of two sister chromatids. Tetrads are commonly found in yeast and used in their genetic analysis.
Big Al, Idaho
What is the easiest way to take a DNA sample from a living human?
     Gary Temple, M.D.: Any cells of the body are a source of the same DNA in that individual, but the easiest sources are those easily sampled from the outside, most commonly inner cheek epithelial cells. These are obtained simply by scraping the cheek walls gently, inside the mouth.
Terry, Palo Alto
What exactly causes Klinefelter's syndrome?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Klinefelter syndrome is a chromosomal condition that happens in men. It is caused by an extra X chromosome. Usually a man has one X chromosome and one Y chromosome. A man who has Klinefelter syndrome has two X chromosomes.
Marifer (Texas)
Do all living things have a genome?
     Carla Easter, Ph.D.: Yes. A genome is all the DNA contained in an organism or a cell, which includes both the chromosomes within the nucleus and the DNA in mitochondria.
dana MA
Approximately, how many questions do you get a day?
     Sarah Harding, M.P.H.: We get about 2500-3000 questions throughout the day. We try to answer as many as we can, but need to pick out a representative group to answer. We're definitely working away to answer your questions!
Bonaly Phrasavath, Los Angeles California
How long did you go to school for your job?
     Barbara Fuller: There are many different levels of education within the National Human Genome Research Institute - with some positions requiring a college degree, and others requiring more advanced degrees such as Medical Doctors and/or Ph.D.'s. I am a lawyer, and went to school for 7 years after high school.
How long does it take for DNA to replicate?
     Pnina Laric, M.S.: Could be as short as 20 minutes or as long as an hour. (It depends on what kind of cells your talking about and what organism they come from.)
Greg Hanson, Bristol TN
Is genetic counseling really ethical? Can't there be unnecessary psychological pressure on the human subject?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Genetic counseling is non-directional. This means that a genetic counselor provides all available information to the person being counseled about their particular genetic question. Genetic counselors do not tell patients whether or not to have genetic testing or treatment. That is the patient's personal decision. You can find more information about the definition of genetic counseling from the National Society of Genetic Counselors.
B.B.S.P.Nag, SMV, Nagpur
What other branches of science are related to genetics.
     Mary Schueler, Ph.D.: Molecular Biology and Bioinformatics are closely related to genetics in that they are both necessary for understanding genetics. There are clinical branches of science that are also related to genetics like Genetic Counseling, Cytogenetics and medicine in general.
Greg Hanson, Bristol TN
I heard that you mapped the DNA of dogs. Has anyone mapped the DNA of other animals?
     Carla Easter, Ph.D.: The genomes of many other organsims have been sequenced including, the chicken, the fruit fly, horse, cow, chimp, cat, plants, rhesus macaque and zebra fish just to name a few.
Vinnie- Eden Prarie, MN
How much of genetics is unkown to scientists?
     Pnina Laric, M.S.: While we know a tremendous amount about genetics, there is still a lot we don't know. We come up with more questions to answer every day!
Are occupations in the field of genetics increasing? Which do you prefer?
     Sarah Harding, M.P.H.: Yes, there are many occupations within the field of genetics, and they are very diverse. Individuals with backgrounds related to law, ethics, policy, sociology, computer science, and many other fields are required within the broad field of genetics. Personally, my background is in public health, which I find very interesting.
Kristen, Crooms, Sanford, Florida
What affects us more, the environment or genetics?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: We don't really know at this point in time. We do know that they both play a role in health and disease. For some diseases genetics likely plays a larger role, while in other diseases environmental factors including lifestyle (e.g. diet and exercise)play a more important role.
Arya from san diego westview
Is there a gene that makes you a good distance runner?
     Barbara Fuller: The most important element in making you a good distance runner is the hard work and exercise a good distance runner endures in training. There may be a gene that could help in muscle formation, etc., but this gene alone could not account for someone who is considered a good distance runner.
Mike New Jersey
whats is a genetic disorder?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: A genetic disorder is a disease that is caused by an alteration in an individual's DNA. Alterations can range from a small mutation in a single gene to the addition or subtraction of an entire chromosome or set of chromosomes.
James west from LOS ANGELES
Can a person rearrange their DNA to look like some one else?
     Carla Easter, Ph.D.: It is very difficult to rearrange DNA on purpose. Also, rearrangements can result in bad things happening. At this point in time, we do not have the ability to accurately rearrange DNA or to retroactively impact are physical attributes.
Ryan, HFCHS Mpls
What made you want to become a scientist?
     Mary Schueler, Ph.D.: I enjoyed science classes in middle school and high school. I went to college as a pre-med student but decided that I was just interested in the biology of people and not really treating them. I enjoy being a scientist because there are so many unknowns and many opportunities to learn things that no one knows.
How common are genetic mutations?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: As Dr. Francis Collins often points out in his public talks, no-one has a perfect genome. The average person has 20 - 30 misspellings in their genetic code. In many cases these misspellings may not amount to anything significant. In other cases, they may predispose a person to serious disease or health problems.
How long did it take you to get as far as you are in your career?
     Carla Easter, Ph.D.: I have been in the field of science for more than 20 years and doing science education 7 of those years.
What experiences did you have in college?
     Pnina Laric, M.S.: I had some wonderful professors who taught me a lot about science. I also played ultimate frisbee and was in a West African drumming ensemble. If possible, study abroad for a semester. Don't be afraid to learn new things!
Brandi,Crooms Academy,FL
How does evolution affect a species gene pool?
     Mary Schueler, Ph.D.: Evolution acts over very long periods of time to remove genes that effect an organism badly and to keep genes in the gene pool that favor an organism's survival.
Greg Hanson bristol Tn
What is your opinion on the idea that people or companies can own our fragments of DNA under a patent?
     Barbara Fuller: DNA patenting is not necessarily a bad thing because the patent system is designed to encourage companies to be able to profit from their research. However, there are times when companies have used their patent to make it difficult for individuals to get tested or to receive treatment.
Thomas Muntaner, St. Ignacious Prep
Are there any special clothing that you have to wear when you work with the DNA- like masks, gloves, etc.?
     Mary Schueler, Ph.D.: There are special safety things we wear depending on what experiment we are doing. Lab coats are often worn and latex gloves are worn for almost everything. The hazards of certain chemicals require us to wear masks and eye protection.
Estrella Luna, Crawfordsville, Indiana
What is the different between your phenotype and genotype?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: A person's phenotype is their physical appearance. A person's genotype is their genetic make-up.
alli and Abby from Florida
How much does the most expensive machine you work with cost?
     Pnina Laric, M.S.: The DNA sequencers I've worked with cost about $350,000 each. We have 14 in our lab!
Caleb Rasmussen, Crawfordsville, Indiana
how much do you guys get paid?????
     Barbara Fuller: The pay for guys (and girls) working at NHGRI has a very wide range - depending on the level of education and the level of responsibility. For instance, some individuals at NHGRI have both an M.D. and a Ph.D. and direct some of the scientific programs - or the entire institute. There are other individuals who perform more technical work, so their salary would be a little lower than those who are in charge of a scientific research project.
Tyler Burdett HPMS
What is it like to conduct genetic experiments?
     Pnina Laric, M.S.: Fun!
Brenna Lewis, Fox Lake, IL.......Hyde Park MS
How was the discovery made that bases are read in threes?
     Carla Easter, Ph.D.: From the National Library of Medicine website Profiles in Science ( Nirenberg and Matthaei created a synthetic RNA molecule outside the bacterium and introduced this RNA to E. coli. They found that their synthetic RNA specified that phenylalanine, an amino acid, be added to the end of a growing strand of linked amino acids, the precursor to proteins. Nirenberg and Matthaei concluded that traces of uracil had directed the synthesis of phenylalanine. On the RNA strand, synthetic RNA made of multiple batches of three units of uracil directed an amino acid chain composed entirely of phenylalanine. One three-unit batch of uracil could be read as UUU (poly-U), which was a three-letter shorthand method or "code word" for identifying phenylalanine. Nirenberg and Matthaei quickly realized that this was the messenger that they had been looking for. Their experiments proved that "messenger RNA," which transcribes genetic information from DNA, directs protein synthesis. That is, messenger RNA transmits the DNA messages that prescribe the assembly of amino acids into the complex proteins that drive living processes.
When the DNA nucleotides are copied onto a messenger RNA and the polypeptide chain does not have a stop codon is this a possible mutation of the DNA itself or does it not become copied?
     Mary Schueler, Ph.D.: It is possible to have a mutation in the DNA sequence that changes a stop codon to an amino acid codon. This will alter the sequence of the polypeptide chain that is read from the RNA. The resulting protein could be harmful by doing the wrong job in the cell or it could be a neutral change. Sometimes these defective proteins are degraded by the cell before they can have an effect.
Anthony, LaRocca Crooms Academy, Sanford, Florida
Is behavior coded in DNA?
     Sarah Harding, M.P.H.: That's a difficult question to answer. Behavior is incredibly complex when it comes to finding the genetic contribution, if any, because the environment plays such a strong role. Many research studies are going on to determine if there are genetic contributions to behaviors, and what those might be.
IF you were interested in Genetics... is becoming a scientist a good idea? if so... why?
     Carla Easter, Ph.D.: Becoming a scientists is one of the ways to study genetics but there are many careers that also relate to genetics like genetic counseling, medical genetics, forensics, patent law, bioethics and others. There are a number of diverse and interesting careers.
Rachell Douglas
Does saliva contain DNA? Why is it that police swab people's mouths?
     Pnina Laric, M.S.: Yes, saliva contains DNA. Police swab the inside of people's mouths (their cheeks), to get a sample of their cheek cells. Forensic scientists, who work in conjunction with the police, can then purify the cheek cells to get to the DNA.
sarah cisek, St. Paul's School for Girls
Does DNA determine how smart you are?
     Barbara Fuller: DNA alone cannot determine how smart you are. Being smart is a direct result of hard work - studying, reading, etc. If there were a gene that could assist in being smart, that gene alone would not be sufficient - and needless to say that there would be individuals considered to be smart that do not have the smart gene.
Ann,palo alto
how much more time do you think it will take to finish the human genome project?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: The Human Genome Project was completed on April 25th, 2003, fifty years to the day that Watson and Crick described the structure of DNA. That is why we celebrate National DNA Day on April 25th!
evan, MA
How do cells make accurate copies of DNA?
     Carla Easter, Ph.D.: The molecule responsible for replicating the DNA is known as DNA polymerase. This molecule is very accurate and has many mechanisms to ensure that few errors are made during DNA repliaction. The error rate for DNA Polymerase is less than 1 error per a billion nucleotides replicated.
Morgan Crooms Acadamy Sanfor Fl
How long did it take to decode the friut fly genome?
     Mary Schueler, Ph.D.: The fruitfly genome was sequenced in about 2 or 3 years. This genome was decoded using a shotgun sequencing method. This is the faster of the two methods used at the time and relies on computer assembly of short sequences without an underlying physical map. A physical map is created with much experimental work analysing the actual physical organization of the chromosomes. This type of effort was done before the human genome was sequenced to ensure that the assembled sequence was accurate.
Britany Wright, Crawfordsville, Indiana
How many people worked on the human genome project?
     Sarah Harding, M.P.H.: That's a great question. There were thousands of people who contributed to the Human Genome Project, from all over the world. It took 13 years to finish, so you can imagine all of the people who played some role in the work.
Blair Cohen & Veronique Adam, Spanish River High
If 99.9% of everyone is the same doesn't that make it easier to find what makes us look different?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: No, actually it makes it harder. A good example is the rhesus monkey sequence which was just published which is 90 - 93% the same as the human genome. And that difference is enough to help us identify some of the differences that might make us human. Another good example is the chimp DNA which was too similar to human DNA (about 98%) to determine which genes might be making a difference.
geoff, newton
What has been the greatest accomplishment and disappointment in the mapping of the human genome?
     Barbara Fuller: Certainly one of the greatest accomplishments as a result of the mapping of the human genome is all the many breakthroughs in human health. We continue to experience many breakthroughs in diagnosing and treating many different diseases and conditions. New breakthroughs are announced on almost a daily basis. The greatest disappointment is that there are still many illnesses that have not had medical breakthroughs in spite of intense and concentrated research.
britt and montie bristol
Yes or No. Do you like working with DNA? Just type YES OR NO. Thanks
     Barbara Fuller: YES!
sylvie and Kyle, Spanish river high
Could the common cold be cured with the knowledge of DNA that we have today? What about in the future?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: The DNA information that we have today provides a basis for eventually understanding and hopefully curing common conditions such as the common cold.
Julia R, Dry Ridge, KY

Information - Moderator Della White, Ph.D, an NHGRI researcher from our Social Behavioral Research Branch is available for your questions!!

How do proteins recognize specific sequences of DNA?
     Carla Easter, Ph.D.: Proteins that bind to DNA recognize specifc sequences and bind to them.
Giovanni Crooms academy, Sanford
If one of your parents have any disease or cancer will you get it to?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Some diseases can be inherited in families - passed on from one generation to the next generation. Other diseases occur sporadically in a family. For instance, a parent or family member might develop the disease later in life. If you have a concern about a particular disease in your family and your chance to get it, I suggest that you seek genetic counseling. A genetic counselor can take and review your family history and talk with you about your chances to get the diseases your parents may have. Information on where you can get genetic counseling can be found on the GeneClinics web site.
Deborah im from baltimore
Are recessive genes passed down every other generation?
     Mary Schueler, Ph.D.: Recessive genes are just like dominant genes in the way the are passed down. They can be passed down in every generation. Recessive genes can only have an effect on the organism (cause disease for example) if it gets two copies, one from each parent.
Maya Troeger Los Angeles CA
What is DNA profiling?
     Barbara Fuller: DNA profiling essentially means making an assumption about someone based on their DNA, and without any other characteristics. For example, making a determination on someone's appearance based on their DNA - when their actual appearance may be very different from what you suspected.
sophie and marielle, spanish river high school
Have you recieved questions from anyone outside the United States?
     Barbara Fuller: Yes. If you look at the transcript of today's chat room, you will see many questions from people from other countries. Look at the questions coming in early this morning, and you will see questions coming from Europe and India.
Blair Cohen & Veronique Adam, Spanish River High
What four bases are in DNA?
     Sarah Harding, M.P.H.: The four bases of DNA are adenine, thymine, guanine, and cytosine.
Blair Cohen & Veronique Adam, Spanish River High
Will we ever be able to clone a dinosaur?
     Carla Easter, Ph.D.: That is an interesting questions. Although we have isolated DNA from dinasour species, cloning a dinasour with current cloning techniques would require that we had viable cells from a dinosaur species that we could manipulate and a surrogate host for the resulting embryo. Unless we can find an easier mechanism for cloning, it may be a long while before we can clone a dinosaur.
Amanda Crooms Acad. Sanford Florida
Can someone change their DNA structure through some new technology?
     Mary Schueler, Ph.D.: Not yet. There are efforts to develop methods to alter certain genes in a person's genome to cure disease but these have not been very successful.
What are some of the most common genetic disorders?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Currently around 4,000 genetic disorders are known with more being discovered. Most disorders are quite rare and affect one person in every several thousands or millions. Cystic fibrosis is one of the most common genetic disorders: around 5% of the U.S. population carry on copy of the defective CF gene.
Andrew, San Diego
Do you think we will ever be able to construct DNA to where we can make the perfect person?
     Barbara Fuller: OK - so define "perfect person." Defining the perfect person is very subjective, so I doubt we could ever reach consensus on what constitutes the perfect person. However, even if we could define the perfect person, I don't believe we would ever want to construct the perfect person.
What is your specific job working on the genome project?
     Mary Schueler, Ph.D.: As a graduate student, I created the physical map for a region of the X chromosome. This physical map was used to verify that the DNA sequence of that region was correctly organized. Now, I create physical maps and generate DNA sequence of the same region in multiple primate genomes. Comparison between genomes helps us understand how chromosomes have changed through evolution and develop testable hypotheses about why these changes have occurred.
Hudson Miller, Crawfordsville, Indiana

Information - Moderator Wendy Introne, M.D., has joined the chat room from the Office of the Clinical Director where she conducts research in rare metabolic disorders. She's here to answer your clinical questions.

Does what what you eat and drink have anything to do with your DNA?
     Gary Temple, M.D.: There are two ways to answer your question. Your genes (DNA) can influence what you eat and how you eat. In fact, a large number of genes have been associated with obesity, and some of these genes can influence (but not absolutely determine) whether a person has certain food cravings, uses binge eating to relieve stress, or overeats, in general, resulting in obesity. The other way to interpret your question is whether what you eat can affect your DNA. What you and most people ordinarily would eat or drink, even if it's not a healthy diet, like too much sugar and fat, or too few healthy foods, probably has no effect on your genes, although there is controversial and weak evidence that certain kinds of foods, like broccoli, may contain anti-oxidants or other chemicals that can help the body protect against cancer, which involves mutations in the DNA of cells. However there are important examples of chemicals you can ingest that CAN affect your DNA and genes, such as when what you eat, drink, or breath contains chemicals that are proven mutagens. One of the best known examples of such mutagens are those in cigarette smoke, that can strongly increase a person's chances of developing lung cancer.
Veronica, California

Information - Moderator Arjun Prasad, B.S., from the Genome Technology Branch is here to answer basic questions about the science of genomics.

My little brother couldn't speak until he was around four. Is speech delay something genetic?
     Wendy Introne, M.D.: Speech delay can be genetic, especially when associated with other findings, such as part of a syndrome. But speech is a complex trait that is influenced by many factors, including environmental exposures. Speech therapy can be very helpful, especially when started early.
Jane, Coral Springs FL
If hair doesn't have DNA in it then why to people take a strand of hair to identify people in the movies and stuff?
     Arjun Prasad, B.S.: While hair is made of protein and probably doesn't contain much DNA the roots contain dead cells that all have DNA in them. Strands of dead hair that fall out often have a bit of root attached that is the source of the DNA.
Henry, MA
How does one go about patenting a gene? When new information is constantly altering our understanding of genes/control, is it practical to patent a gene?
     Barbara Fuller: Patenting a gene means you have not only identified the scientific values for the gene, but you have also identified the functions of the gene. You are correct that new information is constantly altering our understanding of genes, but there are scientifically proven and substantiated qualities that should not change with further research.
St. Ignatius College Prep High School
Why do twins run in families? What causes a woman to be more inclined to have twins if someone else in her family had twins? Are twins genetic?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Identical twins do not run in families, and a history of fraternal twins has influence only if it comes on the mother's side. Identical twins come from the same fertilized egg and are sometimes called monozygotic, which means they share the same genes and DNA. The frequency of identical twins is the same everywhere, about 4 in every 1000 births. Fraternals come from two different eggs. They are really like any two siblings who happen to be born at the same time. Around 12 pairs of fraternal twins are born in every 1000 births.
How are human DNA different from animal DNA, such as dog or cat DNA?
     Mary Schueler, Ph.D.: All DNA has a double helix structure and is comprised of the same four bases and a phosphate backbone. The sequence of the bases is sometimes different and the types of genes are sometimes different. Many genes are the same between organisms - they have the same sequence, the proteins they code for do the same thing and they are expressed in the same cell types. We are now trying to determine which genes or parts of our DNA make us uniquely human by comparison with the chimpanzee genome sequence.
Stephanie Narine, palm beach lakes
Why did you decide to be a scientist?
     Arjun Prasad, B.S.: I ended up in science after trying out several other careers. I worked in computers and in photography among other things. I was always interested in science, and the idea of being an explorer and learning new things that no one has ever learned before drove me towards science. It's great to be able to go to work and play with expensive tools and discover new things.
Big Johnson-TN
Does DNA determine how long cells will live (or the number of times they will divide)?
     Carla Easter, Ph.D.: The DNA is responsible for dictating when the cells replicate. The life span of a cell depends on the type of cell. Some cells will replicate many times and very quickly and other cells may only replicate a few times during their life spans.
JD Furr, Crawforsville, Indiana
Why do scientists even care about DNA?
     Arjun Prasad, B.S.: DNA is pretty neat stuff! :-) There are many reasons we're interested in DNA. It is a major component of all life and its simple structure contains the instructions to make all of the proteins and all of the materials that make up us and all of the living things around us.
joe ward

Information - Moderator Hi everyone! We would like to announce the winners of the American Society of Human Genetics DNA Day essay contest, sponsored by Applied Biosystems. Congratulations to the winners!

Question #1 Winners- If you were a genetics researcher, what would you like to study (and why?):

First place: Lindsay Michalski (11th) Athens High School?? Troy, MI
Second place: Margaret Dietrich (12th) East Kentwood High School Kentwood, MI
Third place: Jason Choi (11th) Montgomery Blair High School Silver Spring, MD

Question #2 Winners: In what ways will knowledge of genetics and genomics make changes to health and health care in the US Possible?
First Place: Elena Perry (9th) Richard Montgomery High School Rockville, MD
Second Place: Sumit Malik (10th) Thomas Jefferson High School Alexandria, VA
Third Place: Nathan Whitmore (9th) Ralph Waldo Emerson Junior High, Davis, CA

Carla, I think it's worth pointing out that Crick and Watson essentially stole their x-ray diffraction data from Rosalind Franklin -- who probably (possibly?) would have arrived at the structure of DNA on her own. Many folks think that she would have received the Nobel prize as well if she had not dead of cancer.
     Carla Easter, Ph.D.: You raise some very valid points.
Geoff Ruth, SF, CA
What is your opinion on the ethics of cloning humans and other creatures?
     Della Brown White, Ph.D.: In my personal opinion, I think there could potentially be negative societal consequences to cloning humans. Human behavior is very complex. I think much care would have to be taken to understand what impact cloning humans would have on how we interact with each other. In terms of cloning animals, that is already being done for research purposes and those procedures are overseen by animal review boards.
How much of your genes takes a part of your physical state? (fitness, speed, height, etc....)
     Wendy Introne, M.D.: Your genes definitely influence your physical appearance, such as hair color, eye color, and height--this is why siblings often look so similar. In terms of fitness and speed, these features are more likely influenced by how much a person trains and takes care of their body.
Christina, Crooms, Sanford FL
Can DNA be destroyed?
     Mary Schueler, Ph.D.: DNA is easily destroyed if it is not in the right environment. DNA is a negatively charged molecule and will degrade fairly readily. It usually exists coated with proteins that protect it, package it and read it. DNA degradation is one of the primary reasons that it is hard to get DNA from fossils. Recent advances in technology have allowed for sequencing of DNA from a Neanderthal fossil.
Landon Hargrove Palm Beach Lakes
How can just one chromosome that is defective effect a child so severely?
     Gary Temple, M.D.: The human genome contains about 20,000 genes, and normal versions of many of these genes are essential to normal development and a healthy body. Each of the 46 chromosomes we inherit from our parents (23 pairs from each) can contain hundreds to thousands of genes. So the loss or disturbance of even a small portion of one chromosome can cause severe disease, or possibly no disease at all.
Nikki K
How expensive is some of the equipment that you use? Our Biotech teacher always goes on about how expensive his micropipets are.
     Arjun Prasad, B.S.: We use quite a bit of very expensive equipment in our work. Because we work at the cutting edge of technology we have to pay a lot for our equipment. I use a lot of fairly large computers that run in the 100's of thousands of dollars. The smaller sequencer in our lab I think was about 80 thousand. (I try not to think about it). The biggest expenses in the lab are actually what we call consumables; the chemicals, enzymes, and other materials that we use.
Blair Cohen & Veronique Adam, Spanish River High
What is RNA restriction and what does it do to the organism it occurs in?
     Carla Easter, Ph.D.: RNA restriction is the cutting or digestion of RNA. The restriction of RNA can cause the shortening of RNA.
Rebecca, Chicago
How do karyotypes work?
     Mary Schueler, Ph.D.: A karyotype is the total chromosome complement of an organism. Karyotypes are often determined to detect abnormalities in the chromosomes that may cause disease. A cytogeneticist takes a picture of the chromosomes through a microscope and then analyzes them against a known control.
Kylie H.
If a childs mother is artifically inseminated is it possible for the child to have DNA extracted to find its father?
     Della Brown White, Ph.D.: DNA testing could be used to help establish the identity of the father. But it would require DNA samples from both the child and the father. There would first have to be some other means of identifying who the parent is and the DNA test would be merely a way to confirm.
brittany, bradford high school
If other primates keep evolving, will they become like us and invent complex machines, like cars?
     Arjun Prasad, B.S.: Other primates are evolving and continue to evolve. A misconception many people have is that evolution tends to push towards more complexity or intelligence, but that isn't always the case. Evolution isn't necessarily directional so that even though primates continue to evolve there's nothing about evolution that says they have to become more (or less) intelligent. We were recently surprised to see even more advanced and extensive tool use among chimpanzees, but I think it is not too likely they'll be inventing cars in the near future.
joe m newton mass
Approximately how many questions do you get asked in one hour??
     Sarah Harding, M.P.H.: Between 1 and 2pm today, we received 790 questions! This is definitely a record for this chatroom. Keep the questions coming!
Cate, Superior WI
Could you please describe the process of transcription and translation?
     Mary Schueler, Ph.D.: During transcription in the nucleus, the DNA ladder is separated into two strands. One strand is read by a protein molecule called RNA polymerase that assembles a complementary RNA molecule as it moves along the DNA. When a stop codon is reached, the polymerase releases the RNA which is then transported to the cytoplasm where the RNA sequence is decoded by a ribosome to create a protein.
Chichinomaco Vaerikalianlioe from Venezuela
What can middle schoolers do to get more people to be involved in National DNA Day?
     Sarah Harding, M.P.H.: A great idea is what you are already doing...logging into the chatroom! We also have great webcast presentations that can be seen at Or, you can do a simple experiment to extract DNA from strawberries. There are many demonstrations of this on the web. Have fun!
Was any part of the genome project figured out before Watson and Crick started their investigation?
     Mary Schueler, Ph.D.: Watson and Crick published the structure of DNA in 1953. At that time, it wasn't even known what the unit or mechanism of heredity was. It wasn't until 1956 that we knew that humans have 46 chromosomes in each of their cells. These could be considered the earliest stages of the human genome project, but the official project as it is now known was not begun until 1990.
emma, newton
Do you think that great medical advances are on the horizon with developing research of DNA?
     Gary Temple, M.D.: The sequencing of the human genome and other animal genomes is definitely speeding advances in understanding and treating human disease. But most common diseases, especially ones believed to be caused by several genes working together, such as diabetes, heart disease, and cancer, are still so complicated to understand that even though great progress will likely be made on such diseases in the future -- at least in part as a result of the new genetic knowledge -- progress will still be gradual and take time.
Gabby G
I've heard that fish odor syndrome is a disease, I wonder if you could die of that disease?
     Wendy Introne, M.D.: Trimethylaminuria, also known as fish odor syndrome, occurs in some individuals who have difficulty breaking down certain foods. The fishy body odor is the primary feature of the disease, although there have been reports of high blood pressure after eating certain foods. It is not a disease that leads to premature death, but affected individuals can become isolated or feel stigmatized because of their body odor.
Pricila, Castaneda, Los Angeles, CA
Have scientists determined what environmental factors affect which traits in children?
     Della Brown White, Ph.D.: There is ongoing research to examine the role that our environment plays in the disease process. As people we are a product of our genes and our environment. Our genes can also interact with our environment and influence our health or risks for disease, but the magnitude of this interaction is still being investigated.
Tlin, Urban
Is a genome just a cluster of chromosomes or is it just something the chromosomes sit on?
     Arjun Prasad, B.S.: A genome is the total DNA content of a cell. We generally don't use the term to describe something outside the DNA in the chromosomes.
Jordan Newton
Does DNA have a color?
     Sarah Harding, M.P.H.: Nope, when DNA is isolated, it is clear.
Jojo From Newton
In which new fields is genetics becoming important (i.e. medicine, farming)?
     Sarah Harding, M.P.H.: Genetics is becoming increasingly important in many different fields including medicine, law, politics, forensics, pharmacology...genetics has certainly played a role in these fields for awhile, but as we learn more and more, the roles are continuing to evolve.
Briana Carroll, St. Ignatius College Prep
What does radiation do to DNA?
     Mary Schueler, Ph.D.: Radiation causes chemical modifications in the DNA that make it unrecognizable to the normal protein machinery that repairs it.
the mazzanator and the stevens
When was DNA day first established and celebrated?
     Sarah Harding, M.P.H.: DNA Day was first celebrated in 2003 with the completion of the Human Genome Project and the 50th anniversary of the description of DNA by Watson and Crick. It continues to be an exciting celebration each year!
Did you guys enjoy science when you were in middle or high school?
     Della Brown White, Ph.D.: Yes, I really enjoyed science and math in both middle and high school. I also had the opportunity to take advanced science and math courses in high school that helped prepare me for college courses.
champanze's and humans have 98% similar DNA, what technology was used to discover that? What traits do we share?
     Carla Easter, Ph.D.: Comparative anlaysis and bioinformatics techniques were used to compare the sequence of the chimpanzee to humans. Because the human and chimp genomes are so similar, there are more genes that we share than are different.
Lappi; Clarkstown North High School, New City, NY
2. How close has gene splicing come to radically altering a specific life form? How close to creating what could be considered a new species have geneticists come?
     Arjun Prasad, B.S.: Genetic recombination has allowed us to insert new genes into animals and plants, but it is a slow and difficult process so only a few genes have been inserted or removed at a time. Bacterial genomes are easier for us to manipulate right now so they've been extensively modified by scientists, but they tend to exchange genetic material naturally between species anyway.
Dan Eggan Ridgewood High School
If identical twins have the same DNA, why do twins' personality differ so much? Does that suggest that personality is not genetic?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Good question Krissy. Identical twins do have the same genetic information and their personalities can be different. Environment, meaning where you grow up, can definitely influence personality but there is a genetic component as well. The genetics of personality is not well studied and more research is needed.
Krissy Cozzi
If the human genome project was to find out the first 3 billion base pairs of the human body system, but everybody has different genes, how would you do that? Or do you just pick a random person?
     Carla Easter, Ph.D.: Everyone has the same genes although there is variation between individual genomes. When the genome was sequenced a number of different peoples' genomes were used in the sequencing of the genome.
Taylor, Las Vegas, NV
Is PCR a possibility in the high school classroom?
     Arjun Prasad, B.S.: It certainly is. The way we do PCR in the lab is to use fairly expensive machines called thermocyclers. They're basically fancy machines to heat up and cool down tubes. The same effect can be had using water baths at different temperatures and manually moving tubes between them. It's not the easiest thing to do, but that is actually how PCR was performed in the lab before thermocyclers were commonplace.
Allen Trang
What is an allele?
     Carla Easter, Ph.D.: An allele is one of the variant forms of a gene at a particular locus, or location, on a chromosome. Different alleles produce variation in inherited characteristics such as hair color or blood type. In an individual, one form of the allele (the dominant one) may be expressed more than another form (the recessive one)
Joe Sanford, nj
is it possible for someone to have yellow eyes?
     Wendy Introne, M.D.: It depends what part of the eye you are asking about. I have not seen yellow irides (the part of the eye that is usually blue, green, brown). It is possible for the sclera to be yellow, also called jaundice. This is a transient finding which is really just a symptom of something else going on in the body.
shinnea wpb,fl
Will there be another opportunity for students to have their genetics questions answered by your staff or will students have access to your answers after today?
     Sarah Harding, M.P.H.: That's a great question. Today is our main opportunity to answer your questions, but we will certainly keep the ones we don't get to today. The transcript from today's chatroom will be available at You'll be able to search the transcript to see if we were able to answer your question, or to search for a specific topic.
maggie ny,ny
What are the most known genes for diseases?
     Carla Easter, Ph.D.: Currently, we know of between 1800 and 1900 genes associated with diseases.
Addie, MD
Is there any special or right way to celebrate DNA day? What do you do besides work in the chat room?
     Sarah Harding, M.P.H.: As part of DNA Day, many of our researchers at the National Human Genome Research Institute have been busy visiting schools in the southeast region of the country. They visit and talk about genetics, their jobs, and what interests them about genetics. We hope that students will take the opportunity to learn something new about genetics, and see why it is such an exciting field.
Alyssa, Madison
Does DNA determine how smart you are?
     Della Brown White, Ph.D.: How well we peform intellectually is based on a number of factors including study habits, school & home environments, and genes. An individual may be born with a great ability to learn and grasp new concepts but if that ability is not nurtured it may never be realized to the fullest potential.
Joseph Egan Fafinski, Peter Isaac Ripple, Holy Family HIGH
Is Down syndrome hereditary, and if so, what is the DNA dysfunction?
     Wendy Introne, M.D.: Down syndrome occurs when an individual has three copies of chromosome 21 (usually an individual has two copies of the chromosome 21). The features of Down syndrome are the result of the extra DNA material.
Ali, Minneapolis
What is the most significant enzyme involved in DNA synthesis?
     Arjun Prasad, B.S.: There are many enzymes essential in DNA synthesis, but I'd say that DNA polymerase is pretty significant. That's the enzyme that chemically adds one base at a time complementary to the template strand.
Louise, madison
How long is the human genome?
     Carla Easter, Ph.D.: The human genome is about 3 billion base pairs in length. If we were to to stretch out all the DNA in one of your cells, it would stretch 6 feet.
Matt, dublin ireland
How effective is gene therapy in combating cancer?
     Gary Temple, M.D.: Gene therapy holds promise for combating certain cancers by replacing or suplementing defective genes involved in the development of cancer. But even the most advanced forms of treatment are still in the experimental phases of clinical testing. One serious barrier to effective gene therapy is finding safe ways to deliver the gene or genetic change to the correct site in the body, without damaging other normal tissues or organs.
Heedeok from Keller, TX.
About how long would all the DNA in all the human chromosomes be if it were strectched out?
     Carla Easter, Ph.D.: It would be 6 feet in length.
Lisle Whitman, Bristol
What is Prenatal Testing? If a mother find that if the fetus inside of her has disorders do you think that doctors would be able to cure the disorders if the fetus is still inside the mother?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Prenatal testing is the term for a group of tests that can be done before the baby is born. This can include chorionic villus sampling (CVS) and amniocentesis which can look at the chromosomes of the fetus. There are some disorders that can be treated while the baby is in utero (inside the mother). For example, in some cases the disorder, spina bifida, which is an opening of the spine can be surgically corrected before birth.
Sejal, L.A. Palm Middle School
Are there any man-made mutants?
     Arjun Prasad, B.S.: There are many man-made mutants, just as there are many natural mutants. Each of us actually has de novo (new) mutations within our own DNA, unfortunately none that we know cause supernatural powers.
Do chickens have DNA?
     Gary Temple, M.D.: Yes, chickens, like all other animals have genes that are made of DNA. Some primitive forms of life, like viruses, however, use RNA instead of DNA to carry their genetic information.
Jasmyne R. California
Does every pregnant mother have to take a prenatal test?
     Julie Sapp, Sc.M.: Pregnant women go to the doctor often to check on how the pregnancy is going and how the health of the mother is. Pregnant women can also be offered a number of tests to try to assess the health of the fetus. These can include blood tests, ultrasound screening, an invasive tests like amniocentesis or chorionic villus sampling (CVS). None of these are mandatory or required and each woman or couple can decide which tests they want (if they want to have any at all).
jasmine b, westchester ca
If we already found out so much about DNA, why is the rest so hard to figure out?
     Arjun Prasad, B.S.: That's the great thing about science, you'll always have something to study. With all we know about DNA there's still far more than that still left to discover. While we know the basic structure of DNA and the sequence of the human (and other) genomes we still know very little about how genes are regulated.
Emma, Brown Middle School
Have you heard about the pain disease Reflex Sympathetic Dystrophy or Complex Regional Pain Syndrome having a genetic Link?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: There is no known genetic cause for reflex sympathetic dystrophy (RSD) which is a neurological condition. There is a lot of research being done to understand this disorder and you can find more information at

Information - Moderator Wow, we are getting some great questions from you. We are trying to answer as many questions as possible. If you don't see yours answered right away, please check back later today. Also, you might want to scan the chatroom to see if a question like yours has been answered already because we try to give priority to questions that haven't been covered. Thanks!

How long does it take to finish a full genetic test?
     Wendy Introne, M.D.: This is actually a difficult question to answer because it depends on the genetic test that is being done. There are cytogenetic tests that look at chromosomes, molecular tests that look at individual genes, and biochemical tests that look at the breakdown of sugar, fat, or protein. The length of time varies--tests looking at chromosomes can take a couple of weeks because cells need to grow in the lab. Some molecular testing can be done faster because techniques like PCR can be done in 1-2 days.
Alondra, Los Angeles
What does radiation do to DNA?
     Arjun Prasad, B.S.: Radiation can chemically alter DNA or cause breakages in the DNA. It can also chemically alter other things in the cell that interact with the DNA and cause damage that way. Each of our cells actually has extensive machinery to repair damage to our DNA caused by radiation, but it can't always repair all of the damage.
Viktoriya B
Will the genome ever evolve in drastic ways that could effect the human race in a negative way?
     Christopher H. Wade, Ph.D.: This is a really interesting question, actually. The answer is yes, it could. If you think about it, evolution is largely influenced by the environment. So, let's imagine that global warming in fact occurs. It is possible that humans will genetically adapt to the new conditions. However, imagine that a comet then hits the earth, cutting off sunlight so that the earth cools dramatically. Then the same evolutionary adaptations which made humans better suited to a warmer environment (say, being super-sweaters) might be negative in a new environment (where the sweat will get rather icy). Part of the reason this question is interesting is that it relates to the question of whether or not humans should control evolution. What if we decide that everyone should have a certain trait (which seems like a good idea at the time), but which is actually maladaptive if the environment changes?
Ashleigh Kringel
How do external factors change a gene?
     Carla Easter, Ph.D.: Mutagens cause mutations within an organism's genome. Radiation is an example of a mutagen. In addition, the manifestation of a genetic disorder can be affected by an individual's environment, including aspects of their lifestyle, like diet. Although these environmental factors may not be physically changing the genes they can still affect the expression of the gene.
Lorissa, FL
Are all syndromes and disorders predetermined by our genes?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Genes certainly play an role in both rare and common diseases. However, the environment (including lifestyle factors like diet and exercise) also have a role. So a person can have a genetic predisposition to a disorder such as cancer or diabetes, but this does not mean that they have a 100% chance to develop the disease.
Charlie, CSHS

Information - Moderator Joining us now are three new experts: Jen Sloan and Julie Sapp, genetic counselors at the NIH Clinical Center, and Dale Lea, R.N. from NHGRI.

How do autoimmune diseases occur in the body?
     Julie Sapp, Sc.M.: The main job of your immune system is to protect your body from foreign substances and infectious agents. This is actually a very complicated thing to do since the immune system needs to recognize what is foreign and what is from you ("self") and then mount a very specific attack against the foreign substance. This is a big part of the problem in autoimmune disorders - the body inappropriately attacks parts of the body because it thinks that those parts are foreign.
Steffi from St. Paul's School for Girls
Can depression be passed down from your mother or father?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Depression does have a genetic component and we do see families where a mother/father and child both have depression. But genetics is not all that is involved with depression, environmental factors such as life experiences definitely play a role.
Hill Top Preparatory
Are there contagious diseases, like Turner syndrome, that have to do with chromosomes?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Turner syndrome is a chromosomal disorder, not a contagious disease. Turner syndrome occurs when a female inherits only one X chromosome from either her mother or father (instead of having the usual two X chromosomes). Turner syndrome usually occurs sporadically.
Amanda D, Westview
Hello, Could you direct me to the link that announces the winners of the National DNA Day Essay Contests. The website said it would be located here, but I can't seem to find it anywhere. Thanks!
     Sarah Harding, M.P.H.: Sure, the winners should be posted on ASHG's website at But if you make your chat window show 100 postings, you can find the announcement by looking at the timestamps. We announced the winners right around 2pm today.
Stephanie Young, San Mateo, CA

Information - Moderator Some of you are sending in questions asking who won the essay context. The winners were announced around 2 pm. Scroll down to that time in the transcript to see who won.

Do you think genetics will have a larger role in our society in later generations?
     Della Brown White, Ph.D.: Yes. Genetics will definitely play a larger role in our society. There is research being done to understand if medications can be developed to treat people based on their individual genetic makeup (personalized medicine). Also it is possible that more genetic tests for disease risk will become more available for use by the public. It will be important for us to understand the ethical, legal and social implications as this research unfolds.
How common is a mutation in the DNA?
     Arjun Prasad, B.S.: DNA mutations are very rare when you consider how much DNA is there. Some scientists have estimated that 10 or so new mutations happen within each generation of people. But when you consider we have more than 3,000,000,000 bases in our genome that's a pretty small amount.
Kj from Newton, MA
I struggle with a couple of different emotional disorders, one of them is Seasonal Affective Disorder. Is this caused by genes and, if so, how?
     Wendy Introne, M.D.: Seasonal Affective Disorder is pretty common (around 1/2 million people in the United States), but at this time is not known to be inherited. Light therapy can be very helpful, but you should speak with your doctor first.
Hilltop Preperatory School
can radiation mess with your genes?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: yes, for example UV rays from the sun (a type of radiation) can cause skin cancer.
Alec Mallinger Colby Barton, Spanish River Community High School, FL
How is it possible to choose the sex of your baby?
     Christopher H. Wade, Ph.D.: There are actually a number of different ways to sort sperm based upon whether it carries an X or Y chromosome. These approaches can filter sperm based upon size (one sex is larger), or by using a dye which can distinguish between X and Y bearing sperm. You would then use the filtered sperm to fertilize the egg. At this point, none of these approaches have a perfect success rate, they just increase the likelihood of getting a baby of one sex or the other.
Miles Davis Plam Beach Lakes
Have all of the genes and the traits they code for been discovered? What are some examples of the genes they have found?
     Carla Easter, Ph.D.: We have probably not discovered all the genes in the human genome. About 1800-1900 genes associated with genetic diseases have been discovered. The gene for hemoglobin, genes related to Alzheimer's disease, the gene related to Cystic Fibosis, and genes associated with pharmaceutical metabolism are examples.
Greg Hanson From Bristol TN
What is the most common genetic disorder? Also, what is the percentage of a person being born with a genetic disorder?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: There are many genetic disorders and one of the most common is Down syndrome, which affects about 1 in 700 babies. It is caused by a person having an extra chromosome 21. All pregnancies have a 3-5% chance of having a birth defect. However some genetic disorders do not show up until later in childhood or even adulthood.
Jore, Palms Middle School,Los Angeles,CA
Is Alcoholism in the genes or is it a choice?
     Della Brown White, Ph.D.: There are scientists who are studying whether there are genetic factors associated with addiction to substances such as alcohol. Human behavior can be influenced by genes, the environment or a combination of the 2. Hence, it is not likely that alcoholism will ever be linked to just genes or just choice.
Casey Olson
Is it possible to be colorblind in more than just green and red? What in your DNA makes someone colorblind?
     Julie Sapp, Sc.M.: The cells in your retina (the back of your eye) that are responsible for perceiving color are called cone cells. Many different genes are important in these cells to allow them to work properly. Although red-green colorblindness is most common, there are many other problems a person can have in their cone cells that cause other types of color blindness. For example, a genetic coundition called achromatopsia can cause a complete inability to see color.
Artie Chearsamran
How old are you?
     Carla Easter, Ph.D.: I am 39 years old
Jim Bob Bristol TN
Michael Crightons new book just came out, and it has a lot to do with DNA, one of the things that I was curious about was that in the novel every trait that a person has could be isolated down to a gene, such as the "Comfort gene" and the "exhilaration gene." Is this possible to do? And if it is, what are some of the other genes that have been isolated?
     Arjun Prasad, B.S.: I haven't read the book, though I'd like to, so I hope I understand the question. Most of our traits are what geneticists call "complex traits" which means that they have a complex genetic origin so there isn't just a single gene or a single allele that controls them. Single genes can have an effect on individual traits, such as propensity to alcoholism, however their effect is moderated by environmental effects and the effects of many other genes. The genetics behind behavioral traits such as exhilaration are ususally quite complex and difficult to study because the effects of environment are so strong.
Charlie Evans Cold spring harbor
If you have the gene for a certain disease, does that mean that, know matter what you will have the disease.
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: It depends on the disease. For example, a person who has a gene for hereditary breast cancer has an increased risk to develop breast cancer. On the other hand, a person who has the gene for Huntington disease has a 100% chance to develop the disease.
Jae C.
What is the DNA mutation that causes an extra thumb?
     Julie Sapp, Sc.M.: There are over four hundred genetic conditions that can cause extra digits, and it is also possible for a person to just have extra digits without any other health problems. Having extra digits on the thumb side of your hand or the big toe side of your foot is called "preaxial polydactyly" and it can be caused by a few different genes, including LMBR1 and GLI3.
Lauren D. Westview
Do you think the movie GATTACA would relate to our world in the future?
     Christopher H. Wade, Ph.D.: I think that any story that tries to think about what the future would be like could be useful in thinking about the future. The key is, the future is yet to be decided, and we have the opportunity to try and direct it. The neat thing about GATTACA is that it does a fairly good job of suggesting possible directions that technologies could take. I would say, however, that the capacity of genetics to predict future disease risk appears to be overstated. Much of disease risk is related to environmental factors.
Emily Pascual
After RNA creates strands of proteins, where do those proteins go and what do they do?
     Carla Easter, Ph.D.: The proteins produced can perform a variety of functions. Some of these functions need to occur in the cell or outside the cell. Consequently, some of the proteins stay within the cell and others are transported outside of the cell. Also, some proteins combine with other proteins and can stay within the cell or travel out of the cell.
What is an amniocentesis?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Good question Jessie. An amniocentesis is a procedure that a pregnant woman undergoes to learn more about the health of her baby, specifically to determine if the baby has one of a few genetic conditions. Some of the fluid surrounding the baby is removed. This fluid called the amniotic fluid contains some of the baby's cells. The cells are grown in the laboratory and examined to determine if the baby has a problem with his/her chromosomes.
jessie hoffer from pals middle scholl in LA CA
What advances have been made in understanding how master genes turn on and off? Have geneticists been successful at turning any master genes on?
     Arjun Prasad, B.S.: Regulatory genes such as transcription factors can turn on and off many genes at once. In model organisms such as fruit flies geneticists have done many experiments modifying developmental regulatory genes and causing all kinds of strange phenotypes like legs growing out of their head.
Ridgewood HS, OH
Della White, what is the Human Genome Project and why was it created?
     Della Brown White, Ph.D.: The Human Genome project was taken on to sequence the 3 billion base pairs found in DNA, identify all of the genes and to make this information available to the public. You can find more details about this project and others like it at
How different is the DNA of fraternal twins?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Fraternal twins share approximately 50% of their DNA. This is the same amount of DNA that full siblings share.
Taylor Phillips-Corliss Palms Middle School
What careers are available to those seeking an M.P.H.?
     Sarah Harding, M.P.H.: There are a variety of careers for those wiht an MPH depending on your interests. For example, if your interests are in epidemiology or biostatistics, you might be involved with public health research. My degree led me to a job in education and community engagement. It's a pretty broad career with many opportunities.
Allen Trang
In a DNA extraction using a common detergent, how is the cell membrane disrupted?
     Arjun Prasad, B.S.: When you do DNA extraction with detergent the cell membrane gets disrupted because it contains an oil-like layer that dissolves in soapy water just like oil and soapy water will mix.
C. Berg Springfield, MO
What is the most important thing about DNA day.
     Sarah Harding, M.P.H.: The most important thing about DNA day is for students to get an idea of how exciting the field of genetics is, and why genetics will continue to play a role in human health in the future.
Sharnelle Berkley
What happens to our DNA after we die?
     Arjun Prasad, B.S.: When we die our DNA is left in our body, over time it will break into smaller pieces and slowly degrade. DNA is actually quite stable and under most conditions will last quite a long time.
Max Hutchens HFCHS
Is epilepsy a genetic disorder?
     Wendy Introne, M.D.: There are some genetic disorders that have epilepsy as a feature of the condition. However, seizures can also occur as the result of a head injury, an infection such as meningitis, or poor blood supply to the brain during birth--to name just a few. Most often, the cause of seizures remains unknown.
Our Biotech class recently transfered a pGLO gene to E. coli. Would scientists be able to do the same with more complex organisms? How about pets?
     Carla Easter, Ph.D.: This has been done in other organisms. To my knowledge, besides bacteria, plants, zebra fish and a bunny have been transformed with a similar gene to the one you used.
Blair Cohen & Veronique Adam, Spanish River High
What are the imitations, or what should the limitations be when using genetics in the courtroom? Can violence be justified by one?s genetics?
     Christopher H. Wade, Ph.D.: The first question is fairly hard to answer, because when you get into legalities and the use of evidence one probably needs to be a lawyer. I would simply state that a minimum requirement would be that the genetic information would need to be accurate and reliable. As for the second part, the general answer is no. Human behavior is highly complex, and is not entirely controlled by genetics (with perhaps some rare exceptions). Therefore, personal responsibility cannot entirely be deferred by claims that the the cause is genetic.
Brett, St. Ignatius College Prep
Is it possible to be born without an immune system? If so, can you create an artificial one?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: People with the genetic condition, Severe Combined Immunodeficiency (SCID), have problems with the function of their immune system. They can receive a bone marrow transplant to improve their immune system function. An artifical immune system is currently not available to treat people with SCID.
BHS Student 3
How can you find out if you are homozygous recessive or homozygous dominate or heterozygous for a certain trait?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Homozygous recessive means that a person carries two copies of a recessive gene such as cystic fibrosis. A person who is homozygous dominant has a gene for a dominantly inherited condition, such as Huntington disease, from each parent who has or will develop the disease. A person who is heterozygous for a certain trait carries one copy of the gene for the trait and one normally functioning disease. Tests can be run in a clinical setting to determine if the trait you are worried about is one of these.
Katie R San Diego, CAlifornia
Are autoimmune diseases genetic? Are there triggers that cause it to start? Does having a strong immune system cause the mistaken response to be worse?
     Julie Sapp, Sc.M.: Autoimmune conditions can have a genetic component and there are genetic conditions where part of the condition is having problems with the immune system. An example of a genetic condition that involves autoimmune problems is called Autoimmune Lymphoproliferative Syndrome. If someone has a strong immune system that helps the person fend off disease.
mhardgrave ny,ny
How often do scientists use DNA in their work?
     Carla Easter, Ph.D.: It all depends on the type of work the scientists does and their field of study. Molecular geneticists would be an example of scientists who use DNA in theior research quite often.
Blair Cohen & Veronique Adam, Spanish River High
Does Biotechnology have a lot of math?
     Arjun Prasad, B.S.: It can. There are many different specific fields within biotechnology research, some of which require quite a bit of math, and some that don't. In research most people will have to have a basic understanding of statistics to interpret research results. Most of my friends who are molecular biologists have to use some basic algebra and statistics, but not very much more than that. Computational biology on the other hand can be very math intensive.
Stephanie Narine, palm beach lakes
Does color blindness genetic?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Yes it can be genetic. Red/Green color blindness is the most common type of genetic color blindness. It can also be caused by environmental damage to the retina
Bobby Magee Hfchs
Can you change the DNA in transplant organs so that they will become compatible?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Not at this time. Since every person's DNA is unique and because DNA is present in every cell of an organ, it would be difficult to change the DNA in a donor organ.
BHS Student 7
Sarah Harding what are different careers for working with genes?
     Sarah Harding, M.P.H.: There are many careers that involve genetics in some way. Some are the more traditional careers, that involve research in a lab or at a computer. Other careers combine different fields with genetics, such as law, ethics, policy, public health, art, writing, the list continues to grow. We need a diverse group of individuals to be involved in the field of genetics and to continue to keep the field as interesting as it is.
Bobby magee HFCHS
How many different types of behavior dieases are there?
     Della Brown White, Ph.D.: Many diseases have a behavioral risk aspect, particularly complex common diseases such as diabetes and heart disease. These specific health conditions can be influenced by exercise and dietary behaviors.
liz Khitrik MA
Is there a gene that decides what subjects in school your good at?
     Christopher H. Wade, Ph.D.: I doubt it, but we honestly don't know yet. Most personality traits will come from a complex combination of the environmental and genetic inclinations. To the extent that they are genetic, they will probably be caused by the interactions of many genes, not one. Therefore, it seems unlikely that knowledge about a gene would predict your abilities in a specific topic (particularly since the environment is a random variable).
Erin and Marissa Florida
Can you get cancer if your parents or relatives have it?
     Wendy Introne, M.D.: It depends on the type of cancer. There are some types of cancer that are known to be inherited. If an individual inherits a gene with a known mutation, then that person's risk for cancer is increased. It is very important to review your family history with your doctor and discuss any concerns you may have.
Bobby Magee HFCHS
What are the chances of getting cancer if your great grandfather had cancer, but no one else in your family?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: That depends on the type of cancer your grandfather had and when he developed it. If you are able to get that information, you could send your inquiry to the Genetics and Rare Diseases (GARD) Information Center, funded jointly by the National Human Genome Research Institute and the Office of Rare Diseases, National Institutes of Health.
Kenzie and Shelby, Minnesota
Is there a way that someone who studies DNA can come to our school and teach us more about DNA??
     Sarah Harding, M.P.H.: The American Society of Human Genetics has organized a great network called the Mentor's Network. It can be seen at You can search for speakers in your region and contact them to invite them to your classroom...they are right in your own backyard!
celeste Levey, Los Angeles
What are the leading causes of DNA damage and can you provide any insight into the new drug, PTC124?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: The new drug PTC124 is being used in clinical trials to treat boys with Duchenne Muscular Dystrophy. For more information visit
Are there and discoveries you have made studying DNA? Also, what are some things scientists are currently trying to figure out about DNA?
     Arjun Prasad, B.S.: We've discovered that regions of the genome that are very similar between species and that don't code for proteins frequently are involved in gene regulation. Right now I'm trying to understand how different mammals are related to each other using DNA sequence information. One of my co-workers is trying to understand the genetics of dyslexia.
Ross Pugatch
is it possible for somemone to have more than 46 chromosones? is it possible to have less?
     Julie Sapp, Sc.M.: Most people have exactly 46 chromosomes and our chromosomes come in pairs. It is possible to have an extra chromosome - we see this in genetic conditions like Down sydndrome, which is caused by having an extra chromosome 21. Having less than 46 chromosomes is less common. Some ways that a person can have less than 46 chromosomes is if they carry a chromosome translocation, which is when two chromosomes break and reattach end to end, or if they have a condition called Turner syndrome, which occurs in girls with just one X chromosome instead of two.
How long does someone need to be in college to get a good job in DNA research?
     Carla Easter, Ph.D.: It depends on what type of job you would like to do. Someone who is working in a DNA research lab would likely have at least a bachelors degree. If someone is thinking of running a lab, they will probably need training in addition to their bachelors degree, and many research labs are run by individuals with graduate training.
Blair Cohen & Veronique Adam, Spanish River High
Why is DNA important in today's society?
     Christopher H. Wade, Ph.D.: Genetic information has been getting a lot of attention lately because it could potentially be used for a lot of medical and non-medical purposes. There is considerable debate about whether these different applications are ethical or not, so it has become a major social and political issue.
What are the possibilities, for the future, to prevent some genetic disorders?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Mapping the human genome has enabled us to find out more and more about genetic disorders. This information is expected to enable scientists and medical researchers not only identify and better treat genetic disorders, but also prevent them in the future.
Ashley Florida, CSHS
Where on this website can you find the experiment to extract DNA from strawberries? It sounds like fun!
     Sarah Harding, M.P.H.: We don't have the protocol on our website, but you can find one version at
Is achondroplasia dominant or recessive?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Achondroplasia is one kind of dwarfism. It is caused by an autosomal dominant gene mutation. A person who has one copy of the dominant gene mutation will have achondroplasia. Having two copies of the dominant gene mutation for achondroplasia is not compatible with human life.
Mike Rotch
What is the most curable genetic disease?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: There are very few if any genetic diseases that are curable. However, many genetic diseases are treatable. The inborn error of metabolism, Phenylketonuria or PKU, is an example of a disorder that is treatable. People with PKU have an enzyme that is unable to convert phenylalanie to tyrosine resulting in a build-up of phenylalanine in the body. Increased phenylalanine can cause damage to the brain. Most children with PKU are on a special diet and/or formula to limit the phenylalanie in their diet.
Ms. Faulconer, Surry County High School
Does DNA entirely determine how smart someone will be? What about how hard they work, or if they do everything ontime?
     Christopher H. Wade, Ph.D.: In most cases, it is fairly unlikely that genetics entirely determine personality traits and mental capacity. A persons environment and education plays a key role as well. That being said, it is possible that genetic information will be able to suggest inclinations towards certain characteristics.
Blair Cohen & Veronique Adam, Spanish River High
If we know how genes work, then why haven't we found a cure for cancer?
     Wendy Introne, M.D.: We are learning more and more about genes and their function, but there is still much more that we need to know. There are many scientists around the world trying to understand what causes the different kinds of cancer, but again there is much work left to do--perhaps by an inspired young scientist like you.
Shianne R
Is there such a thing as a stop anti codon?
     Arjun Prasad, B.S.: The anticodons that match each of the amino acid coding acids are matched on the tRNA. To my knowledge there isn't a tRNA-like RNA molecule that matches stop codons. Some people have suggested that there are short polypeptides that act as anticodons to assist with termination of translation.
Ryan Shakopee
How can the green fluorescent protein function in jellyfish when they do not have a functioning immune system?
     Carla Easter, Ph.D.: The green flourescent protein that is utilized was originally isolated from the jellyfish, Aequorea victoria.
Andrea Mansourian, Anna Worch
Why do certain disorders and diseases show up in certain generations?
     Julie Sapp, Sc.M.: Genetic conditions can be inherited in families in lots of different ways. For example, some conditions are inherited in a way that is called "autosomal recessive." This means that a person with the condition has inherited a gene change from both parents. Even though both parents carry a gene change, neither parent has the condition. For families with autosomal recessive conditions, we usually don't see affected individuals in multiple generations. The gene change is present in many people in the family even though they do not show signs of the condition. Other conditions are caused by "autosomal dominant" gene changes. In these families, affected individuals can be seen in multiple generations.
Chris R. Westview
What is the most common misconception about DNA testing?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: This is difficult to answer. One common misconception is that the technology is currently available to perform a genetic test on all of our genes. We have about 25,000 genes and genetic tests are only available for a few of them that cause genetic conditions.
Serena Yee
Is Chrons Disease a genetic disorder?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: A recent study found a strong genetic link to Chron's disese. Scientists have identified a handful of genes that boost the risk of developing Chron's disease, confirming that the this inflammatory bowle disease has a strong genetic component.
Ryan McLear, CSHHS
Genetically, how different are men and women?
     Arjun Prasad, B.S.: Men and women differ by one chromosome. Men have an X and a very small Y chromosome. Women have two copies of the X chromosome instead. The Y chromosome is very small and has only a very limited number of genes on it, while the X chromosome is very large and very gene rich. Genetic diseases that are more represented in males such as color blindness are frequently caused by genes on the X chromosome because men only have one copy of that gene so if there's a problem with that one copy there isn't another copy to compensate, while women have two copies.
What is the differnece between beta-galactosidase and a beta-galactosidase gene?
     Carla Easter, Ph.D.: The beta-glactosidase is a protein (more specifically an enzyme) that is encoded by the beta-glactosidase gene.
Andrea, Anna
Are safeguards in place to limit access to genetic testing information? Do you think there should be? Is there a forum for public input on the question of how and by whom personal genetic information can be used?
     Christopher H. Wade, Ph.D.: Most genetic testing services have protections in place to protect genetic information, as do holders of medical records. However, there remains the possibility that the information could get out, and it is generally acknowledged that there needs to be stronger legal protections. As for the public input, there are some opportunities for involvement in the legal process. One could also contact your representatives to ask that they support and encourage such legislation.
maggie ny,ny

Information - Moderator Jean Jenkins, RN, Senior Clinical Advisor has just joined us to answer your questions.

What is tour favorite genome to look at?
     Carla Easter, Ph.D.: I would say that one of my favorite genomes would be the duck-billed platypus genome because it is very different from other genomes that have been sequenced. In addition, it has some very unique features.
joe m newton mass
Is it possable to repair mutations in two sex cells and then form the zygote.
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Thanks for your question Austin. Right now the technology is not available to repair a genetic mutation in a sex cell such as a sperm on an egg.
Austin Anderson
Who was the 200th inmate released from prison because they were proven innocent by DNA fingerprinting?
     Sarah Harding, M.P.H.: Jerry Miller was exonerated yesterday by DNA evidence. Visit for more information.
sophie and marielle, spanish river high school
Why did you want to become a scientist?
     Carla Easter, Ph.D.: I have always enjoyed science and I loved the idea of doing experiments that could help solve problems. Science gave me an opportunity to learn something new everyday and also to talk about and teach the things I had discovered.
corey newton
What are some of the factors that contribute to alcoholism being passed down among generations?
     Julie Sapp, Sc.M.: People have observed that alcoholism can cluster in families for a long time. For most families, both environmental and genetic factors contribute to alcoholism. Even though many people are researching this problem, we might never understand what all of these factors are and how they contribute to alchohol dependence.
Kiara, California
Do you envision a day when a family physician would need to have our genetic profiles just like our blood profiles and family history?
     Christopher H. Wade, Ph.D.: It is possible. A lot of people optimistically assume that genetic information will prove to be very helpful in a general clinical context. However, that really remains to be seen. It may be that the expense and complications of dealing with genetic information will inhibit its use in practice. The promise of personalized medicine is intriguing, but certainly should not be taken as a given.
Dan Eggan Ridgewood High School
What are the possibilities, for the future, to help prevent genetic disorders?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Gene therapy is one possiblity for the future that may help to treat or cure genetic disorders. There are currently clinical trials using gene therapy for a few conditions.
juanito, Teapa
What was one of your greatest accomplishments in your career? Why?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Wow, what a great question! Of all of the things I have accomplished (becoming a Board Certified Genetic Counselor; publishing articles in the nursing and genetics literature;authoring two genetics books for nurses) the greatest accomplishment has been the 20 years that I worked in a public health genetics clinic in Maine helping and supporting families who were seeking answers to their genetic questions. The reason that I went into the field of genetics in the first place was that my mother and her brother died at an early age from a genetic condition and there was no one in the health care or our community who could answer our questions and support us. I am most pleased that I was able to help as many families as I could over this time.
Mazza and Freeland
If DNA doesn't tell how smart you are, but how are some people born with a higher reasoning ability?
     Della Brown White, Ph.D.: There are probably some genes that play a role in our ability to reason; however, those genes have not been identified in that capacity. Environmental factors such as study habits and quality of education are important to consider when thinking about an individual's intellectual capabilities.
geoff, Newton
Is it possible to die from fungi?
     Julie Sapp, Sc.M.: The answer to this depends a little bit about what you mean by "fungi." Sometimes a fungal infection can be quite serious, for example, for a person who has a problem with their immune system.
jason anguiano
how is the human gemone project helpful to the future?
     Christopher H. Wade, Ph.D.: The human genome project has opened up the opportunity to conduct research that would have been difficult or impossible previously. The resulting information could have important social and health conseqences.
guillermo from trinity pawling
Do frogs have DNA?
     Faith Pangilinan, Ph.D.: Yes, like all living things, frogs have DNA.
Emma Collins
What is mtDNA?
     Arjun Prasad, B.S.: mtDNA is mitochondrial DNA. We actually have a seperate very small genome in each of our mitochondria (small organelles that generate energy for our cells). Because it is in the mitochondria outside the nucleus unlike nuclear DNA all of our mitochondrial DNA comes from our mother and isn't 1/2 from our father and 1/2 from our mother.
michael, palms middle school
Can DNA be determined before a child is born and how?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: A child's DNA can be tested before birth through a procedure called amniocentesis. However, this is not done routinely and only indicated when a fetus is at risk for a genetic condition, for example when there is a family history.
Stephanie Narine, palm beach lakes high

Information - Moderator Faith Pangilinan, Ph.D., has just joined us. Dr. Pangilinan is a postdoctoral fellow in NHGRI's Genome Technology Branch working to uncover the genetic risks of birth defects (mainly spina bifida).

Do people know what makes some people really small, like 3 feet tall when they grow up?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: There are a many causes of short stature (like being3 feet tall). Having a genetic condition called achondroplasia, a form of dwarfism, causes a person to be small in height. Smallness can also be caused by environmental factors such as poor nutrition or lack of medical care.
Tiffany, Brown Middle school
Do vegetables have Dna because I dont like them
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Yes vegetables have DNA. You can even extract DNA from an onion as an experiment.
How many years of school have you been in to be at the position you are at right now. Did you always want to be what you are right now? How do you like your job?
     Christopher H. Wade, Ph.D.: Wow... this question makes me feel old. I have spent 4 years in college, 5 years as a doctoral student, and I have recently decided to return to get a masters in public health (another 2 years). Ok... I'll admit it: I actually like school. There is something really cool about being in a job where you want to keep on learning. That being said, you don't necessarily have to be in school this long to do scientific research. As for my interests, I have actually been wanting to do this sort of work since I was in high school... where I first started thinking about how science influences society. So, I feel very lucky to be doing what I am right now.
Do food preservatives have an effect on DNA?
     Jean Jenkins, R.N., Ph.D.: Not sure that's ever been shown-good or bad. It's known that diet influences our risk for certain illnesses and food preservatives are a component of that. Hopefully future genomic population studies will be able to define these environmental influences more specifically.
Anna, Scranton Preparatory School
What is Jean Jenkin's favorite song?
     Jean Jenkins, R.N., Ph.D.: Sara Smile by Hall & Oates
I am curious to know why genetic counseling is done for parents following the birth of a child with Down syndrome, since Down syndrome is not an inherited condition.
     Julie Sapp, Sc.M.: Parents who have a child with Down syndrome are offered genetic counseling partly because even though most cases of Down syndrome are caused by having an extra chromosome 21, a small percentage of cases are caused by inherited chromosome rearrangments. Parents of children with Down syndrome could also be considered to be at increased risk for having another child with a chromosome problem because of the mother's age. Another reason parents might want to talk with a genetic counselor could be to give them the opportunity to talk about some of the psychological issues surrounding the birth of child with special needs.
JP from New Jersey
From you're point of view do you think genetic disease are being more understood and we are closer to curing them?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: The mapping and sequencing of the human genome was completed in 2003 and this is leading scientists and researchers to better understanding of many rare and common genetic diseases. These advances area also leading to more targeted, gene-based treatments, especially in cancer.
Is Acid Refulx (GERD) genetic? My mom, myself, and my grandparents have this condition.
     Jennifer Sloan, M.S., Ph.D., C.G.C.: The genetics of GERD has been recently studied in twins in Sweden. It was found that identical twins who share 100% of their DNA were more likely than fraternal twins who share 50% of their DNA to both have GERD. This suggests that there is probably a genetic component to GERD. Researchers are interested in studying the genes involved in the development of GERD.
How does it feel to be on the cutting edge of science?
     Faith Pangilinan, Ph.D.: Exciting! All scientists are really on the cutting edge. It's one of the really exciting things about doing research. You're asking questions in the lab that no one else knows the answer to.
Joe, Minnesota
was is so exiting about being a scientist
     Jennifer Sloan, M.S., Ph.D., C.G.C.: I am involved with research on a few genetic conditions. The most exciting thing is to make progress on understanding the condition and share that information with the patients who have the genetic disease. This gives us all hope for future treatments.
corey newton
How is diabetes passed down genetically?
     Julie Sapp, Sc.M.: Most cases of diabetes are probably caused by both genes and factors in a person's environment such as thier diet and activity level. One goal of the Human Genome Project and other genetic research is to better understand the interactions between our genes and our enviroment and how these interactions contribute to health and disease.
Lauren Arnold
Is Autism more common in boys or girls?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Experts estimate that three to six children out of every 1,000 will have autism. Males are four times more likely to have autism than females.
Jaclyn, New York
Is hair loss genetic?
     Jennifer Sloan, M.S., Ph.D., C.G.C.: Hair loss can be genetic and in some cases can follow X-linked inheritance. Male hormones and environmental factors can also play a role.
bobby, palo alto, california
Did Abe Lincoln really have Marfan's Syndrome?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Some geneticists believe that Abe Lincoln had Marfan syndrome. The reasons they believe this is that Abe Lincoln was very tall and had very long limbs and features. However, we can only speculate based on photographs and paitings of him.
Lauren, Cape Elizabeth ME
Is there actually a gene for obesity and can it be turned off?
     Jean Jenkins, R.N., Ph.D.: Like many diseases, the causes of obesity are complex. Multiple contributing factors (biological, biopsychosocial, behavioral, environmental) intertwine to influence outcomes of genetic predisposition to anything. The search for contributing genes continues with the hope of targeted interventions in the future. Since more than 600 genes, markers, and regions of chromosomes have been linked to obesity it'll be quite a challenge.
Miles Davis, Palm Beach Lakes
Why can't monkeys talk?
     Carla Easter, Ph.D.: It appears that even though we are very similar to chimpanzees (we share 98% of our genomes) there are genes that differ between us. Scientists are exploring the reasons why chimpanzees don't talk. It has been speculated that the inability of chimpanzees to speak may be related to hearing and possibly the differences between chimpanzee and human voice boxes. The foxP2 gene has been implicated in speech development of many organsisms. A number of primates, such as chimpanzees and gorillas, make forms of the FOXP2 protein. The primate form of the protein is different than the form made by humans. It is believed that this difference in the forms of the protein may be a reason why humans can speak and primates cannot.
Siobhan, MA
doesnt the brain control our body? why do we have DNA
     Julie Sapp, Sc.M.: You're right when you think of the brain as being "in charge" of things like moving our muscles, thinking, and talking. However, our DNA is the blueprint our bodies use to grow and develop. Our DNA is organized into genes which are the instructions our bodies need to make proteins. Our brains need special kinds of proteins called "neurotransmitters" to tell our bodies to do things we want to do, like move and talk, and things we don't even have to think about, like breathing, digesting food, and having a heartbeat.
victor, newton ma
Have you figured out the genome for a duck?
     Carla Easter, Ph.D.: The genome of the duck has not been sequenced.
catherine and quackers
What is pharmacgenomics?
     Carla Easter, Ph.D.: Pharmacogenomics is a science that examines the inherited variations in genes that dictate drug response and explores the ways these variations can be used to predict whether a patient will have a good response to a drug, a bad response to a drug, or no response at all.
marjau sauve palms middle school
Is being intelligent caused by your environment or genes?
     Sarah Harding, M.P.H.: Intelligence is neither just your genes nor just your environment. It's a combination of the two. Regardless of whatever potential you may hold, intelligence is mostly dependent on how hard you work and study.
Jarrett Hyde Park Middle School
Could serious diseases like AIDS and Cancer be wiped out in the future by DNA manipulation and gene therapy?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: The mapping and sequencing of the human genome was completed in April 2003. This has created many new avenues of genetic research that are leading scientists to have a better understanding of the genetic component of many rare and common diseases. Researchers are also finding ways to target treatment of conditions such as cancer based on a person's or the specific tumor's genetic make-up. The goal for the future is to develop gene-based therapies to treat serious diseases like AIDS and cancer.
Mike M. from Cape Elizabeth High School
What does a clinical advisor do?
     Jean Jenkins, R.N., Ph.D.: I am a nurse with an idea of the potential implications of genetic research for future health care. That perspective helps me to provide guidance to NHGRI on the educational needs of healthcare providers such as nurses, physicians, and others. Then I help develop resources to prepare those in clinical care settings to learn more about genetics and think about how that can improve patient care.
Dalton Holcomb Las Vegas, Nevada HPMS
I almost had spina bifida when I was little. Faith, how can you get spina bifida? How can you prevent it?
     Faith Pangilinan, Ph.D.: When a human embryo is only 3-4 weeks old, a tube forms that will eventually develop into the spinal cord and brain. If this neural tube doesn't close properly, it can result in improper development of the spinal cord (spina bifida) or brain (anencephaly).

Spina bifida is a complex disease, meaning there are many factors involved, and each case can differ.

The best way to prevent spina bifida is for the pregnant mother to make sure she isn't deficient for folate (a vitamin). Since the evidence for this is so strong, in 1998 the FDA mandated folic acid supplementation of all grain products in the US. So every time you eat cereal, or finish your pizza crust, you're boosting your folate levels. This was done in a huge public policy effort to reduce the occurence of spina bifida, since most mothers don't even know they're pregnant in time to take folic acid supplements.
How is it possible that identical twins can result in different races, for example one is black and the other is white?
     Julie Sapp, Sc.M.: Technically, identical twins have the same exact DNA, so we would not expect them to look different. It is possible for non-identical twins to have different fathers if woman ovulates more than one egg and sperm from more than one man is present at the time of ovulation.
Landon Hargrove palm beach lakes high school
How does the Human Genome Project plan to educate a society that does not have all the information? Do researchers feel a responsibility to educate people on this growing field of study?
     Sarah Harding, M.P.H.: We hope that programs like National DNA Day will help to educate people on the importance of genetics and will inform people on the effect of genetics on health. As genetic technologies improve it is necessary that the public be informed about them so that usefulness can be maximized.
Sam Bailey, St. Ignatius College Prep
Can you change the DNA in a mother's egg to make her baby tall, blonde, or blue eyed?
     Sarah Harding, M.P.H.: At the moment no, such changes are not possible to make to an egg. I would challenge you to think about whether we should use this kind of technology to alter someone's looks if it were possible?
BHS Student 12
What will happen if DNA is mutated?
     Carla Easter, Ph.D.: It all depends on where the mutations occur. If the mutation occurs in the coding region or promoter region of a gene, alterations in the protein or the protein's expression can occur and these alterations can lead to genetic disorders. If the mutations occur in non-coding regions, the effects have unknown implications.
jj plam bach lakes hight
Do you think people in the future might have to copyright their DNA?
     Sarah Harding, M.P.H.: That's a tough question to answer because it brings up whether you think people can 'own' DNA. I do think that individuals' DNA should be protected from potential misuse. At this very moment Congress is voting on a bill that would prohibit genetic discrimination by others such as insurance companies or employers. I do think people should be confident that their DNA won't be misused.

Information - Moderator Kris Wetterstrand, M.S., has joined the chat room. Kris is a Program Analyst working with the Sequences, Maps and Bacterial Artificial Chromosome (BAC) Libraries Program and the ENCODE (ENCyclopedia Of DNA Elements) project.

What is the best way to take DNA from a human?
     Carla Easter, Ph.D.: DNA can be isolated from a variety of places. For example, blood, saliva, hair, and urine can be some of the sources of DNA.
Stephanie Narine, palm beach lakes
Who is your boss?
     Kris Wetterstrand, M.S.: I directly work for Jane Peterson who is an associate director of my division at NHGRI. She is a long time participant in the Human Genome Project.
Benjamin matias
Have you found the genome code for apes?
     Faith Pangilinan, Ph.D.: There are several primates that are in the process of being sequenced for their entire genomes. Gorillas are at the "draft assembly" stage, meaning that the sequencing is pretty much finished but the order of all the sequences on all the chromosomes needs to be finalized.

If you'd like to look up the sequencing status of different species, you can look here:
Reed, Chaska
How come I'm not deaf when both of my parents are?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Genetic factors account for at least half of all cases of congenital deafness (deafness at birth), and can be classified by the mode of inheritance and the presence or absence of characteristic clinical features that may permit the diagnosis of a specific form of syndromic deafness. To answer your question, it would help to know the cause of deafness in each of your parents. It is possible for deaf parents to have a hearing child. You may want to consider going to see a genetic counselor to help answer your question.
Carlos Pabon Jr. from Palm Beach Lakes High School
Is it possible to be XY but appear female externally?
     Julie Sapp, Sc.M.: A condition called "Androgen Insensitivity Syndrome" can cause a person with an XY karyotype to appear female. People with this condition have a change in the androgen receptor gene. This means that during development, their bodies ignore the chemical signals that tell the body to develop male organs. Since the default developmental pathway is female, people with Androgen Insensitivity Syndrome appear female.
Akki, CA
What is gene mapping?
     Kris Wetterstrand, M.S.: Gene mapping refers to finding the location of a gene in the human genome. In other words, determining the chromosome, the chromosome arm and exactly which spot at which the gene resides.
Max Crane Palms Middle School
What implications do you foresee that the discovery of the human genome will have on the medical field, pharmacology and even other health related fields such as physical therapy?
     Jean Jenkins, R.N., Ph.D.: The possibilities are tremendous.As we better understand human genome variation then we can better understand the genetic contribution to health and illness. This will allow the development of better diagnostic tools, consideration of types and frequency of screening tests (i.e., colonoscopy for those at risk for colon cancer at younger ages), improved diagnosis of disease assisting in selection of treatment (i.e., more aggressing disease matched with aggressive treatment), and potential for targeted drug selection based on gene profiles. All of this is considered personalized medicine! This occuring at a rapid pace challenging all care providers to kepp up. But it offers great hope for individuals that will benefit from all these advances. Good question!
Kathrine Bendtsen
What kinds of jobs will this new information create in the future?
     Sarah Harding, M.P.H.: As the field of genetics continues to evolve, the field continues to grow and become more diverse. The career options will continue to grow as well. We need a diverse group of people to get involved in genetics, such as those interested in biology, computer science, chemistry, ethics, law, policy, art, writing, education, sociology... the list will continue to grow and grow.
Maeva from Holy Child
Is cow milk genetically modified?
     Kris Wetterstrand, M.S.: Hello, Spanish River!!!! To be honest, I'm not totally sure. I don't think that milk is genetically modified. Some cows are, though.
Alex mazza, Stenen Freeland
If identical twins was to go for DNA testing for a paternity suit would they be able to tell exactly which twin was the father?
     Carla Easter, Ph.D.: Hello to Mr. Beaver's class i Black Mountain, NC from Mr. Witherlyat NHGRI. A standard paternity test may not be able to distinguish which twin is the father. More sophisticated tests would have to be done in order to establish the paternity.
Kelsey, from Black Mountain, NC
What is Newborn Genetic Screening?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Newborn genetic screening involves obtaining a small amount of blood from a newborn and testing the sample for a set of genetic disorders for which there is early intervention and treatment. The classic example of newborn screening is PKU. When an infant tests positive on their newborn screen for PKU, then they are referred for diagnostic testing. If they are found to have PKU, they can then be given an altered diet to prevent complications such as mental retardation. All states have newborn screening for genetic disorders programs. Some states now screen for 30 diseases.
Valerie D. L.A. Palms Middle School
Can two people who look completly different have similar DNA?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: All people share 99.9% of their DNA. All of uniqueness lies in the one one thousandth of our DNA that is different.
Erin and Marissa Florida
What is the oldest specimen of DNA? What type of organism did it come from?
     Carla Easter, Ph.D.: The oldest, accepted DNA isolated comes from 400,000-year-old plants found in ice in Siberia. (BBC News)
Sam Bailey, St. Ignatius College Prep
If you are born with a disease what percent of your DNA has a mutation?
     Julie Sapp, Sc.M.: Most people with a genetic condition have a gene change that is present in all of their cells. For some conditions, though, only a portion of a person's cells have a gene change. The parts of the body with the change show the condition while the parts of the body without the change do not show the condition.
Sylvie, Newton MA
How do you know if you are a carrier for certain genes?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: All of us are carriers for 7 - 10 recessive conditions. You might never know that you are a carrier unless you have a child with a genetic condition like PKU. Carrier genetic testing for common genetic conditions such as cystic fibrosis is offered to couples who are considering pregnancy so that they can learn whether they are both carriers and have an increased chance of having a child with cystic fibrosis.
kier cape elizabeth maine
Do we now have the ability to change who we are? Can changing our DNA sequence make us more athletic or smarter?
     Sarah Harding, M.P.H.: No, currently we do not have the ability to alter our DNA either for enhancement purposes or to treat diseases. This technology is quite a ways down the road from where we are now. Even if we could change DNA to improve intelligence or athleticism, these characteristics are still heavily influenced by environment, i.e., how hard someone practices or studies.
My name is Micheal Jackson Palm beach Lakes
How many years will it take to become a certified scientist?
     Faith Pangilinan, Ph.D.: There are many kinds of science-related jobs which require different amounts of training. It's pretty similar to working in medicine. Some hospital jobs only require a high school diploma, but to be a nurse or a doctor you need more education. If you would like to run your own lab group at a university or in a company you would need a Ph.D., which is similar to needing an M.D. to be a doctor. A Ph.D. is granted after completing graduate school. So after high school, you'd need a college degree (usually four years to get your bachelor's degree) and then go to graduate school (4-6 years to get your Ph.D.).
Dalton Holcomb Las Vegas, Nevada HPMS
How has DNA Day affected the rest of the world?
     Sarah Harding, M.P.H.: Well, we've had many participants in the chatroom today from places all over the world. One of the first questions we received was from the Netherlands. We hope that the online resources made available today by NHGRI and other organizations participating in the program will be used by people internationally.
How exact is genetic testing? Is 100% correct?
     Jean Jenkins, R.N., Ph.D.: Wow, that's a difficult question to answer. It really varies depending on the type of genetic test. For instance, some illnesses are caused by a single known gene change (mutation)that can be tested (i.e., huntington disease). In that situation the individual either has the gene change or not. For others, the gene test may be able to identify certain gene changes that are known to increase someone's lifetime risk (i.e., breast cancer) but our knowledge of all the genes involved may not yet have been identified. In that case, a range of risk may be provided for someone with a positive gene test (i.e., BRCA1)with actual disease risk influenced by other factors (i.e., environmental, behavioral, etc). Plus accuracy and validity of test results is also influenced by the lab doing the testing.
Alondra, Los Angeles
What makes a stem cell different from a skin cell?
     Kris Wetterstrand, M.S.: A stem cell retains the ability to develop into different types of cells. The skin cell has already experienced changes, such as certain genes being turned on or off causing certain types of proteins to be expressed, to make it a skin cell.
Mitchell H., Palms Middle School, Los Angeles
What causes Hemophilia?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Hemophilia is most commonly caused by a gene mutation on the X chromosome. A woman who is a carrier for hemophilia has the gene mutation on one of her two X chromosomes. Since she has an X chromosome with a normal copy of the gene, she does not have hemophilia. A woman who is a carrier has a 50% chance to pass on the X chromosome that contains the gene mutation for hemophilia. A male who inherits this gene mutation will have hemophilia. A carrier female also has a 50% chance to pass on her X chromosome that is normal to a son who would not have hemophilia.
Michaela, JFK Middle School, NY
How much difference in the genetic code can you find in someone's ancestry?
     Kris Wetterstrand, M.S.: If you compare genetic sequences that you inherited directly from an ancestor, then the sequences will be the same except for mutations that have occured since that ancestor. In general though, all humans are 99.9% the same at the sequence level. So at maximum difference in the genetic code could be only 0.1% different.
Chioma Aso; LA,CA; Palms Middle School
I made a DNA cake, is that an appropriate way to celebrate DNA day? what year was DNA discovered?
     Sarah Harding, M.P.H.: That is fantastic! We have heard about lots of ideas for DNA Day around food, such as creating a DNA model out of twizzlers and gum drops. DNA was first isolated in 1869 by Friedrich Miescher (he isolated the DNA from pus!). You can read more about it in our education kit at (look in the timeline for the 1800's).
Olive Yew, Maine
How come my baby cousin looks more like me than his brothers?
     Carla Easter, Ph.D.: Although we inherit are genes from our parents, your cousin is related to you and probably shares some of your genes. Our appearance is related to a variety of factors and it is not unusual for relatives to look very similar.
Carlos Pabon Jr. from Palm Beach Lakes High School
As scientists, is it hard to choose between the religious view of creation and the scientific view?
     Julie Sapp, Sc.M.: This is a personal issue that many scientists struggle with. As human beings, many of us have questions about our origins and why we are here. Just like other people, scientists vary in how certain they are about their own personal answers and explanations. I think that what scientists and people of faith have in common is a desire to answer these questions, and by doing so, understand more about ourselves and our world.
Julia from Newton, MA
If all our DNA in each cell is the same then how are there different types of cells?
     Kris Wetterstrand, M.S.: Not all genes operate the same in different types of cells. In some cells, only certain genes are turned 'on' and producing proteins. For a muscle cell, only those genes needed to create a muscle cell are working.
John Doe, Westview
Does radiation affect all the genes or just some?
     Kris Wetterstrand, M.S.: Radiation can potentially affect all DNA. The radiation can change the chemistry of the DNA molecule whether it's part of a gene or in a non-genic region.
Andrew, Westview High School
Are the procedures to study the DNA of dogs quite neccesary, or should the money be going towards other DNA investigations?
     Carla Easter, Ph.D.: The understanding of dog genome will provide valuable insight into many human disorders including cancer and narcolepsy. In my opinion, the money spent on the dog genome is money well spent.
Matt Chanhassen, MINNESOTA
How many years did you stay in shool to become a scientist?
     Carla Easter, Ph.D.: I spent 4 years in college and 6 years in graduate school in order to get my PhD in molecular genetics.
shinnea wpb,fl
What is more common beta or alpha thalassemia
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Beta and alpha thalassemia are inherited forms of anemia in which there is a defect in the synthesis of hemoglobin. The estimated prevalence of both forms of thalassemia is 16% in people from Cyprus; 3 - 14% of people from Thailand; and 3 - 8% of populations from India, Pakistan, Bangladesh, and China. There are also prevalences in Latin America, Carribean, and in countries bordering the Mediterranean.
Andrew, Westview High School
How many generations does it take to go from a very dark complexion to a very light complexion?
     Faith Pangilinan, Ph.D.: Skin color is a complex genetic trait that we don't fully understand. Multiple genetic components are expected to contribute to skin color. It really depends on chance and parental contribution.
Suzanne-HFCHS, Victoria MN
How can I get involved in the study of DNA and the genome?
     Sarah Harding, M.P.H.: Right now, enjoy the classes you're taking and use this time to figure out what aspects of genetics and science interest you. You might want to consider looking into summer programs or other opportunities that can help you develop your interests.
Celicia Clarke:mecps in brooklyn NY
Whats the most expensive peice of equipment you use?
     Kris Wetterstrand, M.S.: Probably my computer. That's because I work in an office and help to manage genetic research. I don't conduct research myself anymore. However, I do help to make the decisions about who gets money. The most expensive pieces of equipment in the research that is funded are sequencing machines. They can cost a half a million dollars each.
Cree F westview
Are suicidal feelings genetic?
     Julie Sapp, Sc.M.: First of all, suicidal feelings are serious and if you are thinking about hurting yourself or if someone you know is feeling this way, it's really important for you to tell someone like a parent or school counselor. We do know that there can be a genetic component to psychiatric conditions like depression, which can cause a person to have suicidal feelings. These kind of conditions can cluster in families and in most cases are due to both genetic and enviromental factors.
evan, MA
what can you tell me about prenatal testing?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: I can tell you that there are several types of prenatal testing that are available to couples. There is prenatal screening for spina bifida and Down syndrome, for example. This type of prenatal testing involves analysis of a blood sample from a pregnant woman. If a woman screens positive for one of these conditions, she is offered further diagnostic testing which may involve a high resolution ultrasound or amniocentesis (testing of the fluid from around the developing baby. Prenatal testing is optional as different couples may have different feelings about whether to have or not to have prenatal testing.
camille from palms middle school
Could the advances in genetics ever help cure or treat a disease like MS?
     Julie Sapp, Sc.M.: One of the goals of the Human Genome Project and other genetic research is to better understand how our genes contribute to health. We hope that learning more about our genes can lead to a better understanding of conditions like MS and that this kind of research could contribute to cures for this and other conditions.
Is there a disorder where someone is born with the chromosomes "YY"?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Yes, there is a chromosomal disorder where a male is born with an extra Y chromosome - 47,XYY.
Olivia W. Westview
What is karyotyping?
     Kris Wetterstrand, M.S.: Karyotyping is a way to visualize chromosomes. The chromosomes are arranged and displayed in pairs, ordered by size and position of centromere for chromosomes of the same size and then stained.
Alex T. Palms Middle School
Has there ever been a question that it was so hard that you could not answer it?
     Sarah Harding, M.P.H.: I don't think we've ever avoided answering hard questions, the problem is that we've received so many questions, we have to pick the ones we can answer in the time alotted. We try to choose a representative group of questions to answer throughout the day. Please be sure to check back and read the transcript at the end of the day to see if we were able to answer your question.
Taylor Voges Las Vegas ,NV
How closely are people and purple sea urchins related and how would people find out?
     Carla Easter, Ph.D.: The genome of a male California purple sea urchin was sequenced, and it contained over 814 million letters, spelling out 23,300 genes. The sea urchin had most of the same gene families found in man, the Deuterostome toolkit used to create animals in this superphylum. However, the size of gene families was often larger in humans, reflecting in part two whole genome duplication events during vertebrate evolution, after the separation of the sea urchin and human evolutionary lines. To read more, please visit or website at
Tiffany, Brown Middle School
can dna smell?
     Kris Wetterstrand, M.S.: No. DNA is a chemical molecule. However, there are DNA sequences (genes) that are associated with our ability to smell.
ruby dutton ths
Do dogs see in black and white?
     Sarah Harding, M.P.H.: Yes, that's correct. I believe dogs only have rods in the backs of their eyes (as compared to rods and cones like humans do), and therefore cannot see color.
Taylor Wilson HPMS
Do males have hemophilia more often than females? If so, why?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Yes, males do have hemophilia more often than females. Hemophilia is usually an X-linked inherited condition. For hemophila A, 1 in 10,000 males is born with this condition. For hemophila B, 1 in 34,500 males is born with this condition. Hemophilia A and B are inherited in an X-linked recessive manner. In X-linked inheritance a woman who is a carrier has a gene mutation for hemophilia on one of her two X chromosomes. Since she has a normally functioning X chromosome, she will not have hemophilia. A male who inherits the gene for hemophilia from his mother will have the disorder since he only has one X chromosome.
Jenny Hyde Park Middle School
What is uracil?
     Carla Easter, Ph.D.: Uracil ione of the four nitrogen bases in RNA. The others are adenine, guanine, and cytosine. Uracil replaces thymine, which is the fourth base in DNA. Like thymine, uracil always pairs with adenine
Jahkida Palm Beach Lakes
What was the first genetically modified organism?
     Faith Pangilinan, Ph.D.: Stanley Norman Cohen and Herbert Boyer started simply in 1973 by genetically modifying bacteria.
Alex mazza, Stenen Freeland

Information - Moderator Remarkably for DNA Day, the U.S. House of Representatives, just a little bit ago, cast a historic vote in which it passed the Genetic Information Non-discrimination Act of 2007 by a vote of 420-3. The act prevents discrimination against any individual in terms of health insurance or employment based on their genetic information. The bill now moves to the U.S. Senate, which has unanimously approved a smiliar version of the bill in the last two Congresses. President Bush also has expressed strong support for the legislation.

What organism looks like it will be sequenced next?
     Kris Wetterstrand, M.S.: Just some of the organisms being sequenced and compared to the human genome to illucidate health and disease are the nine-banded armadillo (Dasypus novemcinctus); domestic cat (Felis catus); guinea pig (Cavia porcellus); African savannah elephant (Loxodonta africana); tree shrew (Tupaia species); rabbit (Oryctolagus cuniculus); and a bat species that will be determined based on the availability of a high-quality DNA sample.
the mazzanator and the stevens
what is your job
     Sarah Harding, M.P.H.: I am the Community Outreach Analyst here at the NHGRI. I work on education programs like DNA Day and also work to engage different groups around topics related to genetics. I definitely enjoy my job, it's a lot of fun!
lanay Ny
If two of you're parents have genetic disorders is there a possibility that one of their children may be the carrier?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Yes it is possible. If you have a specific concern you could get in touch with the Genetic and Rare Diseases (GARD) Information Center, funded by the National Human Genome Research Institute and the Office of Rare Diseases, National Institutes of Health.
Jes Maryland
Can you get DNA from Dinosaurs bones?
     Kris Wetterstrand, M.S.: Hello, Palm Beach Lakes!!! I amnot sure if DNA has actually been isolated fromdinosaur bones. Ancient DNA is very hard to extract from old samples, because it can degrade over time and be contaminated by DNA fomr other organisms.
Jahkida Palm Beach Lakes High
What gives DNA it's form?
     Kris Wetterstrand, M.S.: The chemical bonds along the backbones of the double hilex molecule and the bonds between the nucleotides/bases that make up the rungs of the double helix 'ladder'.
Jonathan Medina.San Fransisco,CA
What are the best parts of being a scientist? What are the worst?
     Faith Pangilinan, Ph.D.: My favorite part of being a scientist is the intellectual challenge of figuring out how to ask a question in the lab, and being the first to know the answer. One hard part of being a scientist is that your ideas of how to tackle problems often don't work right away, so you need to be persistent to be successful.
Katherine Newton, MA
How many genes are in a dog?
     Carla Easter, Ph.D.: Dogs have 39 chromosome pairs and about 20,000 genes.
what made the scientist start the human genome process?
     Kris Wetterstrand, M.S.: The Human Genome Project was a started as an effort to undertake a very large and expensive research project in such a way that saved money and took advantage of the expertise of scientists around the world. The main goal was to determine the sequence of all the chemicals (nucleotides) in the human genome thereby creating a resource that all biologists can use to further their research.
jordana kristel cold spring harbor
How many genes does rice have?
     Carla Easter, Ph.D.: The genome is more than 400 megabases in size with an estimated 50,000 genes.
Becky & Kaylagh, MN
Can people with XXY or XXXY chromosomes live healthy lives of normal length?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Life expectancy for men who have XXY is expected to be normal. Men with XXXY (Barr-Shaver-Carr syndrome)resemble men who have XXY.
Kellan Turcy, St Ignacious Prep
To what degree is personality controlled by genetics?
     Faith Pangilinan, Ph.D.: The short answer is that we don't know. Like many traits, it's hard to tell how much personality is determined by environment and how much is determined by genetics. Behavioral genetics is a rapidly expanding field with scientists asking questions like yours.
E.K.....West Chester, PA
What are the differences between a chimp's DNA and a human's DNA?
     Kris Wetterstrand, M.S.: On average the human genome and rat genomes are different at approximately 1% of the bases in their genomes.
Brittany, Bradford Ohio
Who discovered that girls are XX and boys are XY?
     Kris Wetterstrand, M.S.: The XY sex determination system was first described independently by Nettie Stevens and Edmund Beecher Wilson in 1905.
Sadaf A. Westview
How many people in the United States have genetic disorders? How many are carriers of genetic disorders?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Each of us carries 6 - 8 recessive gene mutations that when paired with a similar gene mutation in a partner, can cause a genetic disorder. We do not know the number of people in the U.S. who have genetic disorders as many are undiagnosed.
Can you predict how far away geneticists are from knowing the function of every gene in the human genome?
     Faith Pangilinan, Ph.D.: Honestly, no one can predict how far we are from knowing the function of every gene in the human genome. Although the human genome sequence is known, scientists are still working hard just to identify all the genes, as well as determine what each gene does. Work on related genes in other organisms (like bacteria, yeast, fruit flies, mice, chimps and many more) has accelerated our understanding of what human genes do.
Ridgewood HS, OH
Is it possible to to recieve a gene that absolutely no one in your family has? For example if no your family has ever had red hair and green eyes, is there any way that you could get that combination?
     Kris Wetterstrand, M.S.: No, you can't receive a gene that your family doesn't have. However, you can inherit a trait that isn't apparent in your family. If the gene variant for green eyes are recessive and also carried by both your parents (although they don't have green eyes), you could end up with green eyes.
Isabelle Newton, Ma
On average, What gender lives longer?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Life expectancy for U.S. residents increased to 77.6 years according to the 2003 U.S. census. Females live an average 5.4 years longer than males.
Does a baby have less DNA than a mature adult?
     Kris Wetterstrand, M.S.: Yes, because adults have more cells. Although, the genetic information in babies and adults are the same.
Maddy: HFCHS, Victoria, Minnesota
We are learning about RNA strands. What part of our body do they help with?
     Carla Easter, Ph.D.: There are various types of RNA and they are found inside our cells. Mostly, we associate RNA with protein production. DNA is transcribed into messenger RNA. The messenger RNA is then translated into proteins. Proteins are the "work horses" of the cell. Without the proteins, you would not be able to function. Without RNA, you could not make proteins. Scientists are learning more and more about the different types of RNA that exist and how RNA helps to regulate protein expression.
Liz Komarek Holy Family Catholic High School
Do you guys ever have fun?
     Carla Easter, Ph.D.: We have lots of fun! Who wouldn't have fun working with DNA!
Can DNA tell people how long they will live?
     Kris Wetterstrand, M.S.: Longevity is a very complicated trait. We know about some genes that contribute to living longer and we will undoubtedly figure out more genes that do. However, we don't know enough at this point to really predict things. In addition, environment (what you eat, how much you exercise) plays a big role in longevity.
Brian from HFCHS Minnesota!
How many different amino acid varieties are there?
     Carla Easter, Ph.D.: There a total of 20 amino acids.
Mike Hunt
What types of education must you complete to be certified in your field??
     Sarah Harding, M.P.H.: This depends entirely on what you would like to do. If you want to be in charge of your own lab, it's necessary to have a Ph.D. Other research specialties might require an M.D. or J.D. However for other jobs, master's or bachelor's level degrees might be appropriate. I encourage you to look into the field you're interested in to determine what education level is necessary to get.
Mandy, TN
What if a person has only 45 chromosomes, will they develop any certain dieseases?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: It depends on what chromosome is missing. When a woman is missing one of her two X chromosomes, this is a genetic condition called Turner syndrome. She will have short stature, the possibly of having some learning issues and infertility.
What is your favorite science joke?
     Sarah Harding, M.P.H.: What did one helix say to the other?? "hey, why are you so wound up??"
Erin, Madison
What evolutionary changes do you predict on human genome?
     Kris Wetterstrand, M.S.: Very interesting question. One could imagine that humans will adapt to their current environment which has certainly changed a lot. Think about all the things that we have now that weren't around before: adequate food supply, toxins in the environment, more medicines to treat disease. These things could lead to changes in who reproduces, a necessity for evolution.
Ashish Ingle, SMV Centre for Biotechnolgy, Nagpur India
What did you major in in college and what college did you attend?
     Sarah Harding, M.P.H.: I went to a small liberal arts college called Haverford College and majored in biology. But everyone in this room has a different background. Some of us went to large undergraduate institutions for a microbiology degree, some majored in english, others even majored in medical photography. We've all taken very different paths to end up in this chatroom today!
andrea Mansourian, Anna Worch
Is there an Multiple Sclerosus gene?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: The most comprehensive study to date on multiple sclerosis by researchers at Duke University in 2005 pinpointed a cluster of genes on chromosome number 6 that play a major role in causing multiple sclerosis. An earlier study in 2003 also found a gene that appears to be a risk factor for multiple sclerosis, and may cause the disease to progress more rapidly than normal (gene known as CD24).
Carlos Fernando Castaneda, BIMAC Research Group. Universidad del Cauca. Colombia
Can more then one mutation happen at once?
     Kris Wetterstrand, M.S.: Sure. Multiple mutations could happen at the same time but in different places of the genome. Or multiple mutations could happen in the same place in the genome, but at different times.
Luke, Hyde Park
What is the relationship between junk DNA and evolution?
     Faith Pangilinan, Ph.D.: Traditionally, we've thought of protein-coding genes as being the "important" part of the genome that have been conserved throughout evolution as seen by sequence similarity between species. In contrast, the large intervening sequences were thought to be "junk DNA" because they're not conserved (lack of sequence similarity) between species. However, more recently it's thought that these genomic regions may have elements with previously unrecognized function.
Scott Colorado
What makes the DNA pull apart from the strawberry juice when extracting DNA from strawberries?
     Carla Easter, Ph.D.: There are many steps in isolating DNA. The DNA in a strawberry is located within the strawberry cells. In order to extract the DNA from the cells, we use a detergent to disrupt the cell membranes and release the DNA. We then use salt to stabilize the DNA and alcohol to preciptate it so that we can see it.
Stephanie Narine, palm beach lakes
If two animals "mix," like a liger, does the DNA change a lot?
     Kris Wetterstrand, M.S.: A liger is a hybrid (combination) of a tiger and a lion. Half the DNA of a liger is like a tiger and half is like a lion. So,the DNA is the same as those two animals, but is paired up in a very unusual way.
evan, MA
Do tomatoes have DNA?
     Sarah Harding, M.P.H.: Yes! Everything that is living has DNA.
Dustin HAll, Las Vegas, Nevada, HPMS
Can animals have some of the same genetic disorders that humans do?
     Kris Wetterstrand, M.S.: Yes, absolutely. For example, dogs have some of the same cancers as humans. In addition, scientists have purposefully created models (such as in mice) of human genetic diseases.
Taelor S. Westview
What is the most common disease due to gene mutations?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: One of the most common genetic disorders is Down syndrome, caused by the presence of an extra number 21 chromosome (trisomy 21). Another common genetic disease is cystic fibrosis, an autosomal recessive condition that occurs in 1 in 2500 individuals. Five percent of the U.S. population carries a gene for cystic fibrosis.
Abby and Max, TN
Why do they use mice in experiments -- do they have DNA like humans?
     Sarah Harding, M.P.H.: Yes, mice have many genes that function similarly to genes in humans. So if we study them in mice, and learn about how they function, we can learn similar lessons for humans. There are many other model organisms that are used in research such as the rat, dog, zebrafish, or chicken!
MM from New York
What has been the highlight of your career?
     Kris Wetterstrand, M.S.: As part of my job here at NHGRI, I particpated in the organization and management of the Human Genome Project. Some little highlights are a trip to China and a press conference at the White House.
Jacob Gray; Los Angeles, California, USA
Why wasn't Rosalind Franklin acknowleged for what she did?
     Carla Easter, Ph.D.: There are probably a number of reasons why more people do not know about Dr. Franklin's contributions. Also, Dr. Franklin died before the Nobel Prize for the double helix was rewarded and the Nobel Prize is not awarded to non-living persons.
shinnea wpb,fl
how close is human DNA to that of a chimp?
     Kris Wetterstrand, M.S.: Hey Spanish River! Human and chimps are 99% identical at the DNA sequence level.
kendrick medearis ,delray beach florida
How many genes are there in the human genome?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: There are between 20 - 30,000 genes in the human genome. This finding is one of the big surprises that came out of the mapping of the human genome. For many years, people thought that humans had 100,000 or more.
If you lose an arm, does your DNA change?
     Sarah Harding, M.P.H.: No, if you were to lose a limb, this would not alter your DNA.
Will F Paja, Palms Middle School
Being a professional scientist, your job obviously takes a lot of effort, but does it take a lot of time? is it aggrevating at times?
     Kris Wetterstrand, M.S.: Yes, it does. And it is aggravating at times. As with any job, sometimes things are difficult. Sometimes, I have to do things I don't want to do. But I like my job because it is interesting and challenging, and I feel like I can contribute, at least in a small way, to the betterment of society.
Spencer R
Are there any summer internships or other summer learning programs which you could recommend?
     Sarah Harding, M.P.H.: Yes, the NIH offers summer internships for high school and college students. Information can be found at The application deadline has passed for this year, but check it out next fall if you are interested.
A.K, from Thomas Jefferson High School
Do vegetables have complicated DNA?
     Kris Wetterstrand, M.S.: Chemically they have the same DNA as we do. Obviously, though the genetic sequence is very different. Some vegetables are more complicated because they have more chromosomes or genes. Some vegetables have less, though.
Bianca Hyde Park Middle School
What are some examples of x-linked disorders besides color-blindness?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Some examples of X-linked disorders include: hemophila, Duchenne muscular dystrophy, Fragile X syndrome, X-linked severe combined immunodeficiency (SCID).
justine heritage, St. Paul's School for Girls
What is the latest gene discovery?
     Kris Wetterstrand, M.S.: This may not be the latest, but it is very recent. Scientists have discovered the gene variant in dogs that controls size. In the future, this may help us understand what contributes to size in humans.
If tongue rolling is dominant, why can't neither of my parents roll my tongue? (I'm not adopted).
     Kris Wetterstrand, M.S.: Honestly, I'm not sure. Maybe there are environmental factors that have influenced their (in)ability to role thier tongues.
Who discovered that you could use a Punnet square to predict your traits from your mom and your dad?
     Carla Easter, Ph.D.: The concept of the Punnett square was developed by Reginald Punnett.
Sophie L. Westview
should i be a scientist when im older, will i like it?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: If you already like science and are inquisitive this could easily be the life for you. Everyone in the room at this point loves being a scientist. It is an ever-changing job and seldom ever gets boring. We encourage you to give it some thought!
laura tatro
Are characteristics such as speed, artistic ability, or musical talent inherited? If they are, can they be affected by your environment?
     Sarah Harding, M.P.H.: There might be genetic components to characteristics like the ones you're asking about, but for now research hasn't found anything conclusive that I know of. The environment plays a huge role in what you are asking about, like hard work and dedication to developing a talent.
Michaela - NY
About how many years of schooling do you have to go through to work your way up to where you guys are now in your careers?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Here at the Genome Institute people have a lot of different levels of degrees from bachelors degrees in science and technical fields through PhD's and MD's.
Chris G. New Jersey
Is DNA Polymerase an actual enzyme, or is it made up?
     Carla Easter, Ph.D.: DNA Polymerase is an enzyme involved in the replication of DNA.
Jimmy Boe, Alabama
What reasons are there to take genetic testing?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: There are many reasons for a person to consider having genetic testing. Some of the reasons are carrier testing, prenatal diagnosis, genetic testing to make a diagnosis, genetic testing to see if a person is predisposed to develop a genetic condition. Choosing to have genetic testing, in many instances, is a highly personal one. People often seek genetic counseling to help them make a decision to have a genetic test.
Monica Ide Palms Middle School
Where do babies come from?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Babies come from mommies and daddies.
Madison, Chicago
Do you think that with more research, scientists will find a cure for cancer, alzheimers, and other fatal diseases in teh near future?
     Dale Lea, R.N., M.P.H., C.G.C., F.A.A.N.: Research emerging from human genome discoveries is leading to more targeted, gene-based treatments for cancers such as breast cancer. Such treatments as these are allowing people to live longer and more productive lives.
Jessica B, Cold Spring Harbor
Whats your favorite part of your job
     Carla Easter, Ph.D.: I really enjoy working with students and being able to provide them with information on genomics and the newest innovations in the field. I also enjoy the opportunity to travel around the country and meet different people.
Lilly Astrow, Palms Middle School, Los Angeles

<< View First Half of Transcript

Top of page

Posted: April 25, 2007