Talk

In “The Graduate,” Dustin Hoffman’s character is told that the promise of the future can be summed up in one word: plastics. Well, we’re now clear on the word for 2007: pharmacogenetics.

Today’s must-read article is a short interview with Dr. Mary V. Relling, head of the department of pharmaceutical sciences at St. Jude Children’s Research Hospital, by Claudia Dreifus. Here’s a taste:

Q. How is this tailoring of drugs different from the way they’re currently ordered?

A. Till now, there’s been a one-size-fits-all approach. In most cases, an average dose of a medication is ordered, and then, if the patient suffers side effects, the dosage is adjusted. With gene testing, we can customize the prescription….

Dr. Relling explains why she travels the country advocating its use — “We’ve seen it save lives here. That’s made me a believer.” — and discusses the growth of the field, how it can change medicine, and what this may mean for pharmaceutical companies.

Technorati Tags: pharmacogenetics, PGx, medication, drugs, genetic testing

For those of you interested in breast, ovarian and other women’s cancers, check out Breast Cancer Chronicles if you have not already. Lillie Shockney, R.N., M.A.S. is a nurse specializing in breast cancer and a survivor herself. Her blog provides ongoing information, support and an expert perspective. Recently, she’s posted important info for people concerned about inherited cancers:

• What’s Hereditary About Hereditary Breast Cancer? If you’re asking that question, please read this post.
• Gather Your Family History has helpful advice on doing just that. If you are considering getting a genetics evaluation, the more detailed information you have, the better.

Technorati Tags: breast cancer, ovarian cancer, women’s cancers, family history, genetics

The next big biobank just got the go-ahead yesterday and is set to become the worlds’ largest resource. After a successful pilot this spring, the UK Biobank will collect DNA samples from half a million Britons to study genes, environment and health. Their goal is to identify the genetic components of common diseases, including cancer, heart disease, diabetes and dementia. Over the next four years, the UK Biobank will collect blood samples, lifestyle information and follow-up health information and outcomes from volunteers aged 40 to 69.

The Biobank explains how this significant endeavor is possible (props to socialized medicine):

The UK National Health Service treats the single largest group of people anywhere in the world, and keeps detailed records on all of them from birth to death. Consequently, follow-up of UK Biobank participants through routine medical and other records will allow identification of those who develop a wide range of disabling and life-threatening conditions. This will make UK Biobank a uniquely valuable resource.

We may all benefit from this research, though. Researchers from around the world can apply to the UK Biobank for access to the resource. Privacy hounds are assured that strict systems will be in place to protect participants’ privacy.

The Biobank is funded by the British government, the Wellcome Trust medical research charity and other sources, at a cost of ~$115.6 million.

There are now a handful of large DNA banks underway. With each launch or milestone, comes a flurry of discussion about the promises, perils, and privacy concerns of DNA bank research. What do you think this research will or won’t tell us? Personally, I think DNA-based research will soon be ubiquitous, just as tissue-based research is today. Today’s concerns about privacy and ethics will be passé tomorrow as we establish standards and procedures and get used to the idea that DNA is just part of the personal info out there that we have to protect.

Read more:

UK Biobank’s Ethics & Governance Framework
BBC coverage of the pilot launch of the Biobank
DNA bank initiatives in the States

Technorati Tags: DNA banks, genes, health, diseases, environment, UK Biobank, privacy

Recently there’s been a flurry of discussion about direct-to-consumer genetic testing as a result of the GAO investigation into nutrigenetic testing and presentation to the Senate Committee on Aging a few weeks ago. Many articles have been positive about DNA Direct’s services while being critical of direct-to-consumer sales of genetic tests. Why is this?

I propose it’s because what we offer is really a virtual genetics clinic. We don’t simply sell tests directly to consumers. We strive to provide virtually the education, counseling, screening, and professional oversight that people receive in a physical setting. We use the same medical guidelines and so forth that genetics clinics use. And, we are actively engaged with the medical community and legislators to ensure that our standards raise the bar — and help establish it.

Over at Genes & Drugs, Dr. E offers his thoughts on our services in light of these issues, specifically as they are presented in last week’s New England Journal of Medicine.

Technorati Tags: genetic testing, direct to consumer, genetic counseling, GAO report

Today brings good news for my colleague Jason, the man with the high-octane coffeepot. Earlier this year, research into the pharmacogenetics of caffeine metabolism had him a bit wound-up. But today Jason can pour himself another cup as he ponders the latest news: Researchers have found strong evidence that coffee reduces the risk of several serious ailments, including diabetes, heart disease and cirrhosis of the liver. Yes, coffee even has antioxidents!

Rob van Dam, a scientist at Harvard and author of a review of studies into coffee and risk for diabetes, acknowledges that caffeine could possibly raise the risk for heart disease (by increasing blood pressure and slightly increasing homocysteine levels). But as he tells the New York Times,

I wouldn’t advise people to increase their consumption of coffee in order to lower their risk of disease … but the evidence is that for most people without specific conditions, coffee is not detrimental to health. If people enjoy drinking it, it’s comforting to know that they don’t have to be afraid of negative health effects.

Cheers, java lovers!

(For the non-coffee crowd: have you heard the tasty news about hot chocolate?)

Technorati Tags: pharmacogenetics, caffeine, metabolism, coffee, heart disease, liver disease, diabetes, risk, health benefits, hot chocolate

Tumor typing - or testing the genetic signature of a cancer - is currently helping doctors distinguish between more aggressive and less agressive cancers. As a result, they can recommend treatment that will be most effective for individual patients. Now, researchers have developed a similar test for lung cancer.

The Lung Metagene Predictor (described in this week’s New England Journal of Medicine) scans non-small cell lung cancer cells’ genetic material for patterns that occur in cancers that are likely to reappear. It is 90 percent accurate, its developers said.

If a patient’s tumor shows such patterns, doctors can prescribe more aggressive treatments that are more likely to prevent a recurrence of cancer.

See Scientific American online for details

Lung cancer is the most common form of cancer, and it’s the number one cancer killer in the States. It also has one of the most easily preventable risk factors: smoking. (More statistics)

I had a fascinating discussion yesterday with geneticist Huijun Ring of UCSF about her current research into the pharmacogenetics and -kinetics of smoking. In the not-so-distant future, there may be a “smoking cessation” genetic panel that will tell us about the way in a person metabolizes nicotine and the medications (such as Zyban) that will be most effective in helping her quit.

Technorati Tags: lung cancer, treatment, genes, genetic test, recurrence, smoking, nicotine, pharmacogenetics, pharmacokinetics, buproprion

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

There’s a theme to our water cooler/coffee pot discussions this week: genes and women’s health.

Uterine Cancer May Be Clue to Inherited Cancer Syndrome: A new study showed that 1.8 percent (or about one in 50) of newly diagnosed endometrial cancer patients have inherited mutations for Lynch syndrome, a condition also known as hereditary nonpolyposis colon cancer, or HNPCC. Screening, of course, can reduce risk of further cancers.

Estrogen Therapy, Blood Clots & Genes: So we know that blood clots are usually caused by the confluence of a number of factors — things like being overweight, smoking, taking oral contraceptives, having certain genes. Any of these factors individually increase your risk, and multiple factors compound your risk. So if you’re considering estrogen therapy, you should weigh your cumulative risk for blood clots. The one thing most people don’t know about are their genes, but cheek-swab genetic testing is available for inherited blood clotting disorders.

Multivitamins, Pregnancy & Preeclampsia: If you’re planning a pregnancy, start taking that multivitamin pill now (if you don’t already). It’s a simple, easy thing to do and can significantly reduce your risk for preeclampsia, the leading cause of premature birth and maternal/fetal death. Research from the University of Pittsburgh. Hat tip to Gloria Gamat.

(One of these stories is not like the other, one of these stories is not about genes. But the doula in me says it’s something every woman should know.)

Technorati Tags: genes, women’s health, uterine cancer, estrogen therapy, HRT, blood clots, blood clotting disorders, pregnancy risk, preeclampsia, prevention

Last week, the Senate Committee on Aging had a very public hearing on nutrigenomic testing, four Internet-based companies that offer it, and regulations for at-home genetic tests. The hearing was prompted by a probe conducted by the US Government Accountability Office (GAO).

Interestingly, my colleague Jason was pointing out these issues three years ago, when some of these companies began offering their services. He said, “…nutritional profiling remains a concept under study and is not ready for mainstream consumption.”

In November 2003, Nature ran Erika Check’s article “Consumers warned that time is not yet ripe for nutrition profiling”:

But many scientists argue that it’s far too early for most of these tests to be useful. “The idea of marketing any individual genetic test at this point assumes there is information to justify the use of that test, and we really don’t have evidence that any single genetic marker carries enough information to guide dietary treatments,” says Ronald Krauss, director of atherosclerosis research at CHORI.

Today in Nature, Gene Russo’s article “Home health tests are ‘genetic horoscopes’” provides a tidy bookend:

Advocates of testing point out that the dubious nutrigenetic tests are very different to legitimate, reliable at-home tests for diseases such as cystic fibrosis.

What’s the difference? A key issue that consumers need to look for when considering genetic tests: clinical accuracy, clinical validity, and clinical utility. They mean different things, and for someone considering genetic testing - at-home or otherwise – all three are very important.

Clinical accuracy, also called analytic validity, is the measure of a test’s performance. If a test is looking to see if you carry a particular DNA sequence, clinical accuracy is the degree to which the test will reliably identify that DNA sequence (or the lack thereof). For example, cystic fibrosis testing is over 99% accurate as conducted in certified laboratories. More than 99 out of 100 times, the test won’t incorrectly identify a DNA sequence.

Clinical validity has to do with what a test means. Knowing the DNA sequence isn’t enough; we need to know the degree to which the DNA identifies or predicts a particular condition in order for the test to be meaningful. With cystic fibrosis, we know that if someone inherits two known mutations in the CFTR gene (one from each parent), they will have cystic fibrosis.

Clinical utility. This is the degree to which we can do something in response to knowing about our DNA sequence. If we’ve got a clinically valid test result, we can do things like take preventive steps, make lifestyle decision, choose effective treatment options. If you and your partner are both carriers of CF mutations, you can understand your odds of having a child with CF and make family planning decisions accordingly.

A few other points in this GAO discussion that deserve clarification:

• Not all at-home genetic tests are nutrigenomic tests. There are at-home tests available for clinically valid tests, such as cystic fibrosis, that are recommended under certain circumstances by medical guidelines from physician organizations.

• Not all nutrigenomic tests are direct-to-consumer or at-home. Some tests are being offered at wellness clinics and through alternative medicine practitioners, nutritionists, and other healthcare providers.

I think the bottom line is, as with any decision regarding healthcare choices and medical treatments, be smart. Do your research. Consult with your doctor or doctors (second opinions are never a bad thing). If you’re looking for a miracle pill or a crystal ball, you’re probably not going to find it.

Read more:

• Time magazine’s coverage
• Companies targeted in the GAO probe: Sciona, Suracell, Genelex, Market America
• DNA Direct’s philosophy about all this

Technorati Tags: nutrigenomics, nutrigenetics, nutrition, genetics, genetic testing, direct-to-consumer