Talk

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

At a baby shower this weekend, I had one of my two regular party conversations. Someone says, “Genetic testing? Cool! Do you do all that CSI stuff?”

No, I don’t wield big flashlights and hang around crime scenes. DNA can tell more than one interesting story. In addition to forensics, DNA technology is used for…

Predispositional Tests. These tests can give you permanent, life-long insight. They look at your genetic makeup to see if you carry a gene that puts you at higher risk for a certain disease. This type of testing can also be used to confirm a diagnosis, or determine whether a condition you already have is genetically based.

Screening Tests. Similar to X-rays or other tests that record a moment in time, these tests look at a cell sample for “acquired” DNA mutations (not inherited) that can indicate whether a disease, such as cancer, is present in a part of the body.

Paternity Tests. This type of testing looks at the DNA of a mother, child, and the man thought to be the child’s father, to see if the man is indeed the biological father of the child.

Ancestry Tests. These tests look at your Y chromosome (men only) and mitochrondrial DNA for specific genetic markers that are unique to certain populations. These markers indicate your deep ancestry migration patterns, and thus, genetic ethnicity. (Have I raved about the Genographic Project yet?)

Drug Metabolism Tests. These tests tell you how quickly your body processes certain types off drugs, and whether or not you are likely to experience side effects or toxicity. For some drugs, testing will tell you whether the drug in question will be effective.

So what’s the other party question? “Can you test my dog to see what breeds he’s made of?” (No, not yet :-))

Hot off the press! Scientists just announced the sequencing of the final chromosome in the human genome is complete. This is big news. The sequencing took 150 researchers 10 years to complete.

In 1990, the Human Genome Project launched with a goal of identifying the DNA sequence and genes that provide the “blueprint” for humanity. Chromosome 1 is the largest chromosome, with nearly twice as many genes as the average chromosome. Already, genes on this chromosome have been identified that cause a common form of cleft palate. Research promises that we will soon learn more about common illnesses and diseases like cancer.

Keep in mind that the sequencing is just the first, albeit laborious, step. Now researches get to dig into the data to figure out what the genes on chromosome 1 do, how they interact, and what they mean.

Technorati Tags: human genome project, genes, sequencing, chromosome 1, health, disease

Thank you, Gina Kolata, for continuing to explain both the science and the personal dilemmas of breast cancer treatment research.

Increasingly, oncologists and researchers are focusing on the nature of the tumor itself — “tumor typing” — rather than the location of the tumor when recommending treatments. I expect that very soon, we won’t be diagnosed with “breast cancer.” Rather, we may have “estrogen-receptor positive, HER2/neu amplified, TOP2A amplified cancer located in the breast.”

In addition to HER2 status, estrogen and progesterone receptors, there are other biomarkers currently under study that may help us make treatment decisions.

Genes may also tell us about whether or not we will respond to the treatments indicated by tumor typing. Research is mounting that the effectiveness of tamoxifen depends on which versions of the CYP2D6 gene you inherit.

Stay tuned for more posts on genes and drugs, aka, pharmacogenetics. And a hat tip to Hsien for her latest post on genes and cancer risk.

Update: Read more current posts about tamoxifen here. Also, DNA Direct now offers 2D6 testing for tamoxifen response.

Technorati Tags: breast cancer, treatment, tamoxifen, genes, pharmacogenetics, CYP2D6

As someone with a strong pattern of hereditary breast/ovarian cancer in my family, it’s safe to say that I follow breast cancer news closely. Last month, there was big news from NCI about a study looking at tamoxifen and raloxifene for breast cancer prevention. Many trumpeted the summary findings — “raloxifene is as effective, with fewer side effects!” — but with studies like these, the devil lies in the details.

Denise Grady of the NYTimes dived into these details, and she breaks them down for us in her “second opinion” piece. This is the real news. Women making decisions about treating and preventing breast cancer are faced with a complex challenge of weighing risks, benefits, side effects, and peace of mind. Understanding the real details of your options — and figuring out what they mean to you, personally, can make all the difference in what you decide.

Technorati Tags: breast cancer, tamoxifen, raloxifene, drugs, prevention, treatment, side effects, STAR

Scientists have discovered that a common genetic variant appears to increase the risk of prostate cancer in men who carry it. Specifically, it appears to confer a 60% greater risk of prostate cancer, and may also indicate a more aggressive cancer, when cancer occurs.

This discovery may also explain why African American men have higher rates of prostate cancer than others: This gene variation is about twice as common in blacks than it is in whites.

Kari Stefansson, CEO of deCODE ( www.decode.com) (the Icelandic company conducting the research), sums up why this discovery is so significant:

“This is one of the first genetic variants ever found to confer significant risk of a major cancer among the population in general. Most previously identified cancer genes have their effect on cancer risk only in families with a clear family history of cancer, or are only found mutated in tumors. This discovery is important from a medical standpoint because the only firmly established risk factors for the disease until now have been age, family history and ethnicity. As this variant also appears to be associated with the development of more aggressive prostate tumors, a diagnostic test for the variant may enable doctors to make more informed decisions as to how closely they should monitor those who are at high risk, and how aggressively they should treat the disease once it presents.”

This research is online in Nature Genetics, and will be in print in June

P.S. Interestingly, it’s not clear whether the heightened cancer risk comes from the genetic variant itself or from another that lies nearby on chromosome 8. Sometimes genetic discovery is like that — the gene variant that scientists have discovered may just be a marker that travels along with the gene that’s actually causing the risk. (Prof. John Hawkes offers an evolutionary perspective on this.)

Technorati Tags: prostate cancer, genes, human genome, DNA, risk factors, chromosome 8

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 more I learn about DNA — and as you can imagine, it’s a big part of my job — the more it intrigues and inspires me. I marvel at how this complicated, precise structure provides the rhythm and timing for the intricate biological dances that run through all living creatures. To me, DNA has a musical personality. Like a qawwali, its beauty is collective and improvisational, building on basic themes to create something that is both unique and universal.

So, you can imagine that I was excited to learn that Liz Lerman’s multimedia dance production, “Ferocious Beauty: Genome” makes its West Coast premiere this weekend. Our local paper quotes Lerman, quoting Stanford marine biologist Steve Palumbi: “Scientists in general have this amazing addiction to the joy of discovery… Finding something out is really cool. Addiction to discovery — that’s the mark of a scientist, and the same I think is true of the artist.”

Read coverage of “Ferocious Beauty: Genome”
See DNA art and more DNA art at Genetizen’s blog
DNA-inspired paintings, by Julie Newdall
Commentary on DNA-inspired art, from Nature

Technorati Tags: DNA, art, qawwali, dance, paintings