Archive for the 'Drug Response' Category

FDA Recommends Genetic Test Before Taking HIV/AIDS Drug, Abacavir

Friday, September 19th, 2008

And speaking of personalized medicine and genetic testing for drug response…

The FDA recently recommended that people have genetic testing for HLA-B*5701 before taking the AIDS drug, abacavir (brand-name Ziagen). This test can identify people who carry a genetic marker that is associated with life-threatening hypersensitivity reactions.

Right now, abacavir hypersensitivity reaction occurs in around 8% of patients, and shows up within the first six weeks of therapy.

“The guideline change represents one of the first situations in which a genetic test has been recommended for use in clinical practice to guide drug selection that will affect treatment decisions for thousands of patients each year,” says Dr. Bruce R. Schackman, associate professor of public health and chief of the Division of Health Policy in the Department of Public Health at Weill Cornell Medical College. Dr. Shackman is the lead author of a new study that evaluated the cost-effectiveness of genetic testing for abacavir hypersensitivity.

Abacavir is often used in “cocktails” with other antiretrovirals, including Epzicom and Trizivir.

From FDA’s materials for healthcare professionals:

Information for Patients to Consider if they are taking Abacavir:

  • Some people are at greater risk for serious allergic reactions when first starting treatment with abacavir or with medications containing abacavir in a combination medicine. We can test for a risk factor for such reactions, which is called HLA-B*5701, before giving abacavir. Tests for HLA-B*5701 are readily available.
  • If you test positive for HLA-B*5701, then your doctor will take that into account for your medical care.
  • If you test negative for HLA-B*5701, you are at lower risk of a serious allergic reaction when taking abacavir, but it could still occur, and you still should be watchful.
  • Even if you have previously taken abacavir without a reaction before but have never been tested for HLA-B*5701, you should still be tested before taking abacavir again.
  • If you and your doctor decide that the benefits of starting abacavir outweigh possible risks, then you should watch for any sign described on the warning card. Abacavir HSR may include a combination of the following symptoms: fever, rash, generally ill feeling, extreme tiredness or achiness, gastrointestinal symptoms (nausea, vomiting, diarrhea or stomach pain), and respiratory symptoms (shortness of breath, cough or sore throat). If you develop a combination of any of the symptoms or signs of a reaction that are listed above, then you should contact your doctor immediately.

According to statistics from the Centers for Disease Control and Research, there are 233,079 HIV-infected people in the U.S., and 448,871 people were living with AIDS at the end of 2006. Between 5% and 8% of HIV-infected patients are positive for HLA-B*5701.

  • To see the full FDA Label for Abacavir and other info from FDA for medical professionals: go to this page and click on the second link, “Prescribing (Label) Information from Drugs@FDA”
  • If you are looking for HLA-B*5701 testing, DNA Direct can coordinate testing for you and your doctor: call our Clinical Services Department at 1-877-646-0222 or email expert@dnadirect.com.

Warfarin Sensitivity, Iverson Genetics, and Personalized Medicine on NPR

Wednesday, September 17th, 2008

Last week, NPR’s “Morning Edition” did a story on the way companies and entrepreneurs are beginning to develop and market products tailored to the genetic makeup of individual patients.

Notably, the story featured Iverson Genetic Diagnostics and their test for warfarin sensitivity. Warfarin (brand-name Coumadin®) is a commonly used blood-thinner, but doctors often have a hard time finding the right dose for patients. Too little and it’s not effective. Too much and it can cause dangerous bleeds. As Trish wrote in the previous post, last year FDA updated the label on warfarin to recommend genetic testing to determine the appropriate dosage.

Iverson Genetic Diagnostics, is one of DNA Direct’s partners. Iverson offers physicians DNA Direct’s customized, Web-enabled tool for physicians. This tool gives doctors who are testing their patients for warfarin sensitivity, DNA Direct’s Personalized Reports for their patients. These reports explains patients’ test results in a clear, plain, interactive format. They are personalized to each patient’s actual test results, and explain what the results mean in terms of warfarin dosing, They also describe how genes affect drug response, and outline the most appropriate next steps.

In addition, doctors can download a copy of their patient’s lab report and a clinical summary letter. In turn, patients may return to their online report at a later date to determine how their “metabolism status” may impact drug response for other medications.

”Morning Edition” note that that genetic testing is on the rise for response to drugs that treat diseases like cancer and AIDS. Experts say that genetic testing holds tremendous promise to improve healthcare—and accordingly, the space is filling with entrepreneurs such that the $2 billion DNA testing industry poised to grow from to $15 billion in the next ten years.

At DNA Direct, we believe this growth reflects continued progress toward a truly personalized approach to medicine, and we were pleased to see warfarin testing—an important tool to properly determine treatment—and Iverson highlighted as a bellwether in the field.

Warfarin Response Testing: Medicare Calls for Feedback on Reimbursement

Friday, September 5th, 2008

Guest post from Trisha Brown, MS, CGC, DNA Direct’s VP of Clinical Affairs:

FDA announced last year that the agency would update the label for the blood thinner warfarin to note that patients’ genetic makeup could strongly influence their response to the drug. Too high a dose of warfarin, and patients may experience uncontrolled bleeding—which can be fatal; too low, and patients risk developing life-threatening blood clots. Correct dosing is imperative for administering warfarin, which is the second most common drug, after insulin, implicated in emergency room visits for adverse drug events (1).

Now, the question is whether Medicare should cover the cost of genetic testing to identify the two genes that can affect patients’ reactions to warfarin. The outcome will be momentous and far-reaching: whatever the verdict from the Centers for Medicare & Medicaid Services (CMS), major private insurance companies are likely to follow suit. This week, CMS called for public comment on their decision.

Since FDA’s labeling change, there has been some debate among experts on using genotyping to prevent a significant number of adverse reactions to warfarin, or simply following the patient’s progress using a lab test that checks on how well the blood is clotting, called an INR (international normalized ratio) and adjusting accordingly. The latter view comes largely from thought leaders who work in major medical centers with distinct advantages: physicians can develop best practices; can use a single lab to assess the INR; and effectively communicate dosing changes and recommendations across a single healthcare team. (more…)

FDA Warns Breastfeeding Moms: Genes and Codeine Risk

Friday, August 24th, 2007

With the recent FDA’s activity in personalized medicine, I asked DNA Direct’s director of pharmacogenetics, Dr. Huijun Z. Ring, if she’d give us a guest post.

Huijun writes:

FDA warns breast-feeding moms of genetic risk for using codeine products
Gene test can help to prevent life-threatening side effects in nursing babies

When I was home with my first baby, my training in science and medicine went out the window, and I found myself to be as much of a novice as every other new mother. I wanted to make sure that everything was perfect. Mostly, however, our family went forward by trial and error, learning as we went along how to care for our new member. Gratifyingly, a recent advance in my field of pharmocogenetics will help remove one uncertainty for mothers.

Codeine is a frequently used medication for mothers after child birth and for infants in their first year life. On Aug 17, the FDA issued a Public Health Advisory warning that a rare, but sometimes life-threatening, side effect of codeine in nursing babies could be attributed to a mother’s genetic makeup. (more…)

More News Coverage: Warfarin Gene Test

Tuesday, August 21st, 2007

MSNBC provides compelling statistics about how genetic testing for warfarin (Coumadin) dosage can make a difference:

FDA economists estimate the genetic testing could prevent 85,000 “serious bleeding events” and 17,000 strokes a year, according to a November 2006 study posted to the Web site of the American Enterprise Institute. The savings to the health care system could be $1.1 billion a year, though some people question that. The genetic tests can cost $125 to $500. About 2 million people start taking the drug each year.

Warfarin sends more than 43,000 people to the emergency room each year, the FDA economists said. That total is more than for any other drug except insulin, which diabetics use.

The Washington Post has a suprisingly brief article, pointing out that

Studies have shown that the risk of a serious bleeding episode — into the brain or intestine, for instance — is highest soon after treatment has begun.

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FDA Gives Nod to Gene Test for Warfarin

Friday, August 17th, 2007

Yesterday the FDA announced a new label for the blood thinner, Coumadin (generic: warfarin). The new label explains that people’s genetic makeup may influence how they respond to the drug, and that a $300-500 genetic test can help physicians tailor the drug dose to increase effectiveness and reduce the serious risk of bleeding.

The FDA says:

Warfarin is a difficult drug to use because the optimal dose varies and depends on many risk factors including a patient’s diet, age, and the use of other medications.

Patients who take a dose larger than they can tolerate are at risk of life-threatening bleeding. Those who receive too low a dose are at risk of equally dangerous blood clots. Dosing is particularly important at the beginning of therapy, when problems in adjusting the dose can lead to complications such as bleeding. …

A person’s genes “encode” enzymes and differences in the sequence of a gene can cause differences in enzyme activity or sensitivity. That is why different people process the same drug differently.

Good news, right? Another example of personalized medicine and how it can revolutionize patient care. Unfortunately the wheels of the machine grind slowly, and defensively. So it will be interesting to see how quickly this testing becomes routine: Will it become routine in top medical centers first, as new technology often is? Or, will Medicare bite at the potential for significant emergency room savings by making the gene test mandatory before prescribing warfarin, a drug so common in their population. (more…)

Pharmacogenetics and the Great Melting Pot

Friday, January 26th, 2007

When I was in grade school in the 1970s we celebrated the bicentennial of the United States. In my memory, it was the biggest, longest birthday party ever. A big theme in our studies before and during 1976 was the US as the “Great Melting Pot” — of people, of languages, of cultures. Schoolhouse Rock even provided the illustrations.

Now it’s the 2000s and, guess what, I’m still talking about the melting pot phenomenon with colleagues. But this time, it’s the melting pot analogy* applies in terms our genes:

“Pharmacogenetics/genomics has the potential to benefit people worldwide and to reduce the health disparities between developing and developed nations. This goal is unlikely to be achieved by relinquishing the notion of personalized drug therapy tailored to individual genetic characteristics–the original promise of pharmacogenetics–in favor of a model (pharmacogenomic?) of population-based drug development and prescription, with all its potential pitfalls, especially when extended to admixed populations in developing or developed nations.”

(more…)

Warfarin DNA Test in the News

Friday, January 12th, 2007

The Washington Post has an unusually lengthly article on DNA testing to determine warfarin dosing. Recently, I blogged about the launch of this testing: “Warfarin Sensitivity Test Launches.”

Warfarin (brand name Coumadin) is a popular blood-thinning medication used by about 2 million Americans. It’s prescribed after surgeries, strokes, blood clots, and to prevent blood clots. Medco Health Solutions and the Mayo Clinic are collaborating on a project using this testing to determine initial dosing for patients.

Epstein and other experts say the warfarin projects comprise the first broad use of personalized medicine, or targeted therapy, in which a person’s genetic makeup is used to pick the best medicine or dose. This approach essentially adjusts for differences in body chemistry that explain why one pain reliever or allergy pill works great for you but not for your mom. … (more…)

Media Buzz: Access to Genetic Testing

Wednesday, January 10th, 2007

Happy new year, everyone! I just returned from an unusually exciting break (more on that in later posts) to find that genetic testing is the cover story of this week’s US News & World Reports:

Unraveling Your DNA’s Secrets: Do-it-yourself genetic tests promise to reveal your risk of coming down with a disease. But do they really deliver?

Also, you can now listen to public radio’s December 21 Health Dialogues’ program online:

Genes, Disease and Difference

The program begins with the story of a woman who pursued genetic testing for tamoxifen efficacy, but the panel discussion is wide-ranging, with perspectives from all over the industry.

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The Top 6 Genetic Stories of 2006

Thursday, December 21st, 2006

I’d say that this year’s stories ran the spectrum from “what’s in our genome?” to “what does it say about us?” to “what should we do with that information?” Yes, here’s science to policy in six easy pieces!

Diabetes Risk Genes Are Confirmed. The body of research behind this discovery is impressive, covering populations around the world and all hitting publication in a very short window of time. (I think Denise Grady, a health journalist at the New York Times captured this best with the context of a personal perspective.) With news about Americans’ skyrocketing diabetes rates, our overweight children, and our heaviest nation status, you’d think this genetic news would have made a bigger splash. Stay tuned in 2007 and let’s see what happens once testing becomes available.

The FDA Recommends Relabeling Tamoxifen - In October, the FDA met to review a compelling body of research that shows 7-10% of people may not receive medical benefit of tamoxifen, because of their 2D6 genes. This is an historic first for pharmacogenetics: it’s the first time FDA has recommended relabelling for the effectiveness of a drug, not just toxicity warnings (e.g. atomoxetine/Strattera for ADHD). It’s also notable that certain SSRIs, particularly Paxil, interfere with the metabolism of tamoxifen just like these genes do - so taking both Paxil and tamoxifen effectively cancels out the benefit of the tamoxifen. Please indulge me as I proudly say that my company is on the ball - we began providing this genetic test to consumers and doctors in October, right after the FDA’s recommendation came out.

(more…)

Tamoxifen, 2D6 and How Doctors Get Their News

Friday, December 1st, 2006

Since DNA Direct first began offering CYP2D6 testing for tamoxifen efficacy last month, we’ve had calls from women asking, “how come my doctor didn’t recommend this?” and “why doesn’t my doctor know about this?”

Dr. Kevin Knopf, a respected medical oncologist who specializes in breast cancer, has an explanation in his post this week “Something to Worry About? Tamoxifen Effectiveness.” He wrote this post upon first learning about tamoxifen and 2D6 — from his newspaper. He says:

It is also interesting how oncologists and other doctors find out about news this big – were it not for my newspaper I don’t know when it would first come to my attention (I’ll let you know next month!) When I asked my partner if he had heard about it, it was news to him. There are often no “mass broadcasts” of “breaking news” –e.g. nothing on my email yet. So this can create anxiety for patients who might see something before their oncologist does. I think the best approach would be to let the information get absorbed prior to making any decisions about tamoxifen and to seek guidance from your personal oncologist.

(more…)

What We’re Talking About This Week

Wednesday, November 29th, 2006

Copy Number Variation in Our Genome. Over at Evolgen, RPM explains “recent work indicates that there’s also quite a bit of variation amongst individuals in the actual content of their genomes. Such variation is known as copy number variation (CNV) or copy number polymorphism (CNP). What it means is that some people may have one copy of a genomic region, other may have two, and even others may have none.” What does this actually mean? Read RPM’s commentary and Hsien’s explanation. Or, read Reuters’ boiled-down news. Or, check out Nature’s accessible but detailed article.

Proof is Scant on Psychiatric Drug Mix for Young. Many psychiatrists and parents believe that drug combinations or “cocktails” help for conditions such as ADHD. There’s a lot to be debated about this, and when it comes to children, all our concerns about drug risks are amplified. Studies in children are fewer, children’s bodies and minds are evolving, and children don’t usually get to choose for themselves. What do you think? (more…)

FDA Update: Tamoxifen & 2D6 Testing

Thursday, November 16th, 2006

The only recent coverage I’ve seen so far about the FDA’s relabeling of tamoxifen on is from the PGx Reporter, which is subscription-only. Here’s their public excerpt:

FDA Panel Leans Toward Including CYP2D6
Dx in Tamoxifen Label, But is Split on Language

The Pharmaceutical Science Clinical Pharmacology Subcommittee was split over whether the label should “recommend” the genetic test or make it an “option” for health care providers and patients to discuss.

As it considers just how strong the wording on the label should be, the FDA is looking at the role of endoxifen (the active metabolite), 2D6, and drug interactions.

We’re getting many inquiries ourselves into the Tamoxifen 2D6 Test. Here are recently asked questions and answers, and previous posts on Tamoxifen and 2D6 Testing.

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Warfarin Sensitivity DNA Test Launches

Thursday, November 16th, 2006

Have you had a blood clot or DVT? If so, chances are you’ve been on warfarin (brand name: Coumadin). Warfarin, a blood-thinner, is the most commonly prescribed drug for preventing and treating blood clots.

Warfarin is also known to be a difficult drug to manage, for two reasons. First, the blood levels in which warfarin is effective are very narrow, which means doctors need to carefully calibrate the dose. Secondly, people have a wide range of responses to it, which means calibrating the dose is more challenging.

Kimball Genetics (a laboratory) has just launched a genetic test for warfarin sensitivity, which better predicts an individual’s response to warfarin. This test can help your doctor determine the warfarin dosage that’s best for you — lowered risks, maximum effectiveness. (more…)

National Geographic on “Personalized Medicine”

Monday, November 6th, 2006

I just returned from vacation to find a great article in National Geographic about how genomics is - and will increasingly - affect the practice of medicine: Personalized Medicine Promises Tailor-Made Diagnoses, Treatments

Here’s a clip to encourage you to go check it out:

The genetic variations can be used to identify susceptibility to a particular disease and to pinpoint targets for drug treatments.

Currently drug courses are often ineffective. Physicians may have to prescribe several different treatments before identifying one that works.

“Personalized medicine is about changing the medical paradigm,” said Edward Abrahams, executive director of the Personalized Medicine Coalition in Washington, D.C. “It promises to replace trial-and-error medicine with a more targeted get-it-right-the-first-time approach.”

(more…)

What We’re Talking About This Week

Wednesday, October 25th, 2006

Widespread Study - Adverse Drug Reactions. A study developed by the CDC, FDA and Consumer Product Safety commission shows that harmful reactions to medicines send more than 700,000 Americans to emergency rooms each year. Over 700,000. to the emergency room. The study’s authors and other experts agree that this number is probably low because bad drug reactions are also likely to be misdiagnosed. This is yet another reason why PGx testing can revolutionize medicine.

New Gene May Help Predict and Treat Chronic Pain. People who have a certain gene variant are at lower risk of developing severe chronic pain and are less sensitive to painful stimuli, researchers report. Besides the potential for diagnosing the risk of chronic pain, the discovery offers a starting point for identifying new painkillers.

Portraits of an Artist with Alzheimer’s. A talented artist throughout his life, William Utermohlen provided a window into the experience of Alzheimer’s from the individual’s perspective. While there are some genetic markers associated with Alzheimer’s, their relationship isn’t fully mapped out yet and so testing for risk isn’t ready for prime time. While DNA Direct often receives calls from people wanting “a genetic test for Alzheimer’s”, we don’t offer testing for multiple reasons (see the comments below this post).

In Case of Emergency: ICE Your Cellphone. To aid emergency workers, doctors are encouraging people to add an “ICE” contact into their cellphones. ICE stands for “in case of emergency” and provides emergency workers with a way to find your nearest and dearest, as quickly as possible, should you be unable to communicate with them. Everyone, go program your phones now!

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Genetic Test for Response to Tamoxifen

Thursday, October 19th, 2006

Ryan (the CEO and founder of DNA Direct) and I just returned from an FDA meeting where members of the Clinical Pharmacology Subcommittee, a group composed of doctors and researchers, made an important decision about the breast cancer drug tamoxifen. As Lisa Lee described last week, the purpose of this meeting was to decide whether to recommend changing the tamoxifen package insert, also known as the drug label, to include information about how the 2D6 gene is a predictor of response to tamoxifen.

Clearly the decision of the Subcommittee is a historic moment, both for the emerging field of pharmacogenetics (or how genes influence a patient’s response to drugs) and, most importantly, for the breast cancer community. After all, hundreds of thousands of women are on the drug tamoxifen, and more women are put on the drug every day. The fact that some of them may not be receiving full benefit from tamoxifen because of their genes — therefore increasing their risk of cancer recurrence — could not be more important for breast cancer patients to know about.

So, what did the Subcommittee recommend? (more…)

Tamoxifen & 2D6 Genes

Saturday, October 14th, 2006

Speaking of breast cancer - we’re on a roll this month! - there are very important happenings at the FDA next week. On October 18, the FDA will to evaluate recent research regarding 2D6 gene variants and response to the breast cancer drug, tamoxifen, and whether this research warrants any warnings or changes to the tamoxifen package insert.

Here’s a link to the FDA’s Executive Summary on Tamoxifen and 2D6. (Clicking this link will download a .PDF.)

In concert with the hearing, DNA Direct is launching our first drug metabolism test: 2D6 testing with personalized test results interpretation for tamoxifen. (Testing can be ordered online at the Genes&Drugs website.) Below is DNA Direct’s backgrounder, which explains the test, the research and why we’re offering 2D6 Tamoxifen testing to certain patient populations.

TAMOXIFEN & 2D6 BACKGROUNDER

Recent research on tamoxifen has shown that potentially up to 7-10% of women with breast cancer may not receive the full medical benefit from taking tamoxifen, because of their unique genetic make-up. These women have a special version of a gene (CYP2D6, commonly referred to as 2D6), which may reduce the effectiveness of tamoxifen and increase their chance of breast cancer recurrence. With over 500,000 women currently taking tamoxifen, this research has wide-reaching implications. (more…)

Breast Cancer In The News

Saturday, October 14th, 2006

I’ve been looking for something other than breast cancer to talk about since I just posted on hereditary breast and ovarian cancer, because September was Ovarian Cancer Awareness Month…but I can’t avoid it. Everyone’s wearing pink ribbons and news about breast cancer abounds:

Stay tuned for more info on the FDA hearing next week….

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Tailor-Made Medication

Tuesday, August 29th, 2006

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.

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Don’t Sweat Your Cup of Coffee

Tuesday, August 15th, 2006

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?)

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New Blog: Genes & Drugs

Monday, July 24th, 2006

In the midst of all this talk about genes, drugs and genetic testing comes a brand new blog called — you guessed it! — Genes & Drugs. I’m pleased to announce the launch of this new blog by Dr. Alan Eshleman. While we muse over what the latest news on pharmacogenetics might mean for patients, Dr. E will be talking about the ins and outs of PGx for physicians and other healthcare professionals.

Dr. E has a long history of contributing to online and offline communities. For many years he moderated health & medical communities at The Well. More recently, he wrote “Doctor E’s Diary” for the San Francisco Chronicle’s online site.

If you are as excited about the promise of pharmacogenetics as I am, you’ll want to check in regularly with Dr. E.

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Tamoxifen, Genes and Efficacy Rates

Tuesday, July 11th, 2006

I am thrilled to see discussion in today’s NY Times about the promise of genetic testing for drug metabolism. In particular, I’m excited to see mainstream media discussion of tamoxifen efficacy and genotype.

Much has been made of research published in the past few months regarding aromatase inhibitors — to what degree they prevent breast cancer recurrence, long-term survival, overall survival, and to what degree they’re better than tamoxifen (current studies indicate ~2-3%). That’s very exciting.

What you’re not hearing about, and which could take treatment decision-making to a higher level, is research into gene variants that may indicate who is likely to respond to tamoxifen and who isn’t. This could alter what we’ve previously thought of as tamoxifen efficacy rates. Gina Kolata explains and quotes Dr. David Flockhart, a leading researcher in this area:

(more…)

Codeine, Breastfeeding and Your Genes

Tuesday, June 6th, 2006

Some women carry multiple copies of a gene that metabolizes codeine into morphine. These women process codeine at much higher rates than the average person, which means that when they take an average dose of codeine, it is rapidly converted to unusually high levels of morphine.

For new mothers prescribed codeine after childbirth, this can be a tragic cocktail for their babies. A recent study in Canada reports the death of a newborn from morphine overdose via breast milk.

Babylune notes, “This is not a reason to stop nursing. This is a reason to stop taking codeine.” I say it’s also a reason to consider genetic testing for drug metabolism.

The gene involved in codeine metabolism is called CYP2D6. It metabolizes around 25% of all commonly prescribed medications. It’s also involved in the metabolism of some over-the-counter meds, herbal supplements, and even some foods. Knowing your genetic status is useful information if you’re prescribed or considering taking any drugs metabolized by CYP2D6.

Our company will soon be offering drug metabolism testing — and you can be sure I’ll be the first in line for it. Stay tuned!

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Not All Genetic Tests Are on TV

Monday, May 22nd, 2006

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 :-))