Talk

Amy Harmon looks at the issue of privacy, fear of discrimination, and the very real repercussions some people are facing as a result of the tension between important medical information and lack of comprehensive legislation to protect patients’ genetic privacy.

She quotes Francis Collins, director of the National Human Genome Research Institute at the NIH, “It’s pretty clear that the public is afraid of taking advantage of genetic testing. If that continues, the future of medicine that we would all like to see happen stands the chance of being dead on arrival.”

I don’t think it’s as dire as that, but all of us — patients, physicians, industry and thought leaders — need to push for systemic solutions. Genetic testing is redefining the practice of medicine, and our convoluted infrastructure of delivering healthcare needs to adjust to accommodate it.

Harmon’s profiles of people who have chosen to test, not to test, and to test anonymously by paying for testing themselves illustrate how this tension has a fundamental impact on peoples’ health and families’ lives: (more…)

Right on the tails of my last post comes ground-breaking news about identical twins: they don’t actually have identical genetics! (Darn close, but not 100% identical.)

A study by University of Alabama, Birmingham researchers challenges the long-held belief that identical twins have identical genetics. They compared the DNA of sets of twins and discovered significant copy number variation (or CNV).

…[S]ubstantial chunks of DNA sequences were missing, doubled or reversed in one of the two twins. Having chunks of DNA sequences shifted around or missing is a common genetic mutation. When first discovered, scientists thought it was inconsequential. Often it is, but researchers are beginning to learn that sometimes CNV can be a major factor in developing a disease. (more…)

I’ve got twins on my mother’s side and twins on my father’s side, too. On my mother’s side, they seem to appear every other generation, so the joke among my cousins is “which one of us will have the twins?”

Whether twins really do run in families or whether this is an old wives’ tale is a question many people ask. Senior genetic counselor Lisa Kessler, just answered that over at MedHelp’s genetic forum, where she is the moderator.

She explains that having identical twins is not typically something that runs in families, butBirth control and family planning
Choosing a primary care provider
Ewing�s sarcoma
Family troubles - resources having fraternal twins does — and it happens more frequently after the second pregnancy. Interestingly, this only applies to a history of twins on the woman’s side of the family. A history of twins on the father’s side doesn’t increase the chance of having twins.

So now we know. And now it’s up to my cousins to pass on the family tradition of twins!

Last fall I posted on Ashkenazi Jewish genetic diseases, a number of inherited diseases that occur primarily in people of AJ descent (as a result of the “founder effect“). AJ diseases are commonly known about within the AJ community, but many non-Jewish people are completely unaware of them.

As a result of carrier screening (the ability to test parents-to-be to see if they carry a mutation for the conditions), the actual rates of individuals affected with these disease is dropping. That’s the good news. That people who are appropriate for testing don’t know about testing is the bad news. (My rant on that will have to wait until next week, when the Week of Science challenge has ended)

So here’s the skinny on how these disease are inherited, why people are “silent” carriers, and why carrier testing works:

(more…)

Almost every ethnic or demographic group has higher rates of certain genetic diseases than the general population. There are a number of genetic conditions that are relatively unknown, but terribly debilitating – and all occur most frequently in people with Ashkenazi Jewish ancestry:

• Bloom’s Syndrome
• Canavan Disease
• Familial Dysautonomia
• Fanconia Anemia
• Gaucher Disease
• Mucolipidosis IV
• Niemann-Pick Disease
• Torsion Dystonia
• Tay-Sachs Disease

How is it possible that certain diseases are more common within the Ashkenazi Jewish population? (more…)

There an increasing number of conditions for which certain a gene variant (or multiple variants) increase your risk for developing disease. These variants doesn’t guarantee that you will get the disease, and not having it doesn’t guarantee that you won’t. But they tell you about your risk.

Denise Grady of the NY Times discusses the findings of a gene variant involved in Type 2 diabetes, and the test that might be available as early as 2007 or 2008.

Dr. Kari Stefansson, Decode’s chief executive, said genetic tests that measure the probability of developing a disease “are a new sort of information that our society is growing rapidly more accustomed to, but it is still not absolutely clear how we are going to use it.”

The first use of a Type 2 diabetes test, he said, would probably be in people with impaired glucose tolerance. Those who came out positive could be treated aggressively, perhaps with drugs. Those who tested negative could be offered a more conservative approach.

For people with a family history and normal glucose tolerance, Dr. Stefansson said, the best use of the test would be to test both the relative with diabetes and the concerned family member. If both tested positive, then the family member was at high risk and could try to do something about it.

What would Grady herself do?

Right now, I’m leaning toward having the test if it becomes available. I’m not sure what I’d do with the results or whether they would mean anything for my future. But I’d like the information, and the right to decide for myself whether to act on it.

(DeCode Genetics is the Icelandic company that discovered these gene variants.)

Technorati Tags: diabetes, genes, risk, treatment, family history, type 2 diabetes, denise grady, decode genetics

Would you bank your family’s DNA? Why or why not? Post a comment and let us know!

Here’s why we’re talking about DNA banking: Last week, the Wall Street Journal ran an in-depth article on the recent push to study families with inherited cancers. Says the WSJ:

“One reason families with inherited cancers are so valuable to research is that they make it much easier to home in on the problematic genes. To find culprit genes in a vast population of patients with varying genetic makeups can be almost impossible. When the people getting the disease are all related, it is often easier for researchers to detect relevant genetic patterns.”

Or, as the head of a familial-colon-cancer study puts it, “In families, there are more needles and less haystack to search for the cause of the cancer.”

There’s a fascinating piece of research and discussion in today’s Nature, about a potentially new function that RNA may play in heredity and the expression of hereditary traits. Up until now, RNA has previously been considered a messenger that translates our genetic code (DNA) into proteins, which are the building blocks of our body.

Now, it seems that (at least in terms of certain experimental mice) RNA may actually influence the expression of hereditary traits.

Says Paul Soloway of Cornell University in the discussion piece: “A particularly intriguing possibility is that such RNAs regulate other non-genetic modes of inheritance, such as metabolic or behavioral imprinting.”

What does this mean to the rest of us? Genes are just as important as they ever were, but we already knew they aren’t the full story. They’re just the first chapter. Of a book that is still being written. (Stay tuned for the next installment)

Read a good summary of the research from Scientific American

Read a more detailed account from HealthDay

Technorati Tags: genes, RNA, heredity, inheritance patterns, research

Why be aware of cystic fibrosis? As many as 1 in 25 people in the US is a CF carrier. And that’s a pretty high carrier rate for a condition that most people don’t know about.

Cystic fibrosis, or CF, is an inherited disease that affects the lungs, digestive system, sweat glands, and male fertility. If you are pregnant - or thinging about getting pregnant - you should know about CF.

You might be suprised to know:

• A simple genetic test can help you find out if you are a carrier. If you are, you can figure out your chances of passing on that CF mutation to a child. If your partner is also a carrier, you have a 1 in 4 chance of having a child with CF.
• CF occurs in all ethnic groups, but people with European or Ashkenazi Jewish ancestry are more likely to be carriers than others.
• CF mutations can be passed down “silently” for many generations, without anyone in the family ever having CF.
• This is why medical guidelines say that everyone who is pregnant or planning a pregnancy — and everyone with Caucasian ancestry — should be offered CF carrier screening.
• In rare instances, people with frequent lung infections or chronic sinusitis are diagnosed late in adulthood as having CF. (Most people don’t hear about “mild” CF.)
• There are over a 1000 known CF mutations, and scientists are learning more about what they mean every day. Treatments are continually in development, and people with CF are living longer and healthier lives than before.

Want to learn more or spread the word about CF? The Cystic Fibrosis Foundation is a great resource that has been providing information, support and advocacy for 51 years. (Here are more resources.) Looking for support? The Lawrences are a family blogging about their experiences of raising their children, including a daughter with CF.

Technorati Tags: cystic fibrosis, CF, carrier screening, genetic testing, pregnancy, disease

The NIH is looking for sisters of women who’ve had breast cancer. Why? For one of the first long-term studies to look at how genes and environmental factors — homes, workplaces, and communities — affect women’s risk of breast cancer.

The Sister Study is exciting for a number of reasons:

• They’re enrolling 50,000 women. Such a large study will give more powerful results.

• They’re studying women from various racial and ethnic groups. Women of color have historically been underrepresented in research and have different risk issues. For example, African American women have higher rates of death from breast cancer.

• They’re studying women from different generations. By gathering information about jobs, geography and medical history, they can uncover about environmental factors and breast cancer risk over time.

If, like me, you Race for the Cure in honor of the women in your family – consider giving a bit more: give yourself. Participating by donating and advocacy is important, but partipating in scientific research is another. The progress of science depends on people participating in scientific research. So often, the people being asked to participate are patients or survivors. This is a great opportunity for us, the supporters, to give something truly valuable that can improve the lives of the generations to come. Thanks to Dr. Hsien Hsien Lei for drawing attention to the Sister Study and the importance of participation.

Read Sister Stories from study participants
See if you are eligible to enroll in the study

Technorati Tags: breast cancer, BRCA testing, DNA testing, genes, genetics, sisters, clinical trials

Your genes are like family heirlooms: They get passed on from generation to generation. Everyone’s heard the phrase “it runs in the family,” but not everyone has considered what this actually means.

Learning about your family health history is a lot like putting together your family tree, only you do it through the lens of health and medical stories. Knowing about things that “run in your family” can be valuable knowledge for both you and the generations that come after you.

The CDC has a great, web-based program that helps you build your family health tree, or as genetic counselors call it, your “pedigree.” Check out: My Family Health Portrait

If pen and paper are more your style, the Genetic Alliance and colleagues have a wonderful guide called “Does It Run in the Family” (PDF) with advice and stories for how to gather family health stories, and examples of how to draw your own family tree.

Technorati Tags: family, health, genes, genetics