June 1, 2010

Debate Ensues on Over-the-Counter Genetic Testing

Earlier this month, a company announced its plan to offer over-the-counter genetic testing kits. The news generated considerable debate, as this would be the first time an over-the-counter genetic test has been available directly to the public.

The FDA, though, responded to this plan with a letter to the company indicating that their product met the definition of a medical device and would therefore require FDA approval. The agency indicated that they could find no such approval on file, and asked the company to respond within 15 days with either an FDA approval number or an argument for why one shouldn’t be needed.

The House Committee on Energy and Commerce has also jumped into the fray. In a letter [PDF] to the company planning to offer OTC kits, the committee asked for, among other things “All documents relating to the ability of your genetic testing products to accurately identify consumer risk,” and “All documents regarding your policies for processing and use of individual DNA samples collected from consumers.”

This is not the first time, however, that genetic testing has been available to consumers – other companies have been offering what is essentially mail order genetic testing, including testing for BRCA mutations. The Committee also sent letters to two other companies which have been offering these services, such as 23andme.

Aside from issues of FDA approval, the presence or absence of mutations does not tell the whole story of an individual’s health risk. For example, in the case of BRCA1 and BRCA2 mutations, a positive or negative test cannot specifically predict whether or when an individual woman might develop cancer (or determine that she will not develop cancer). As Merrill Goozner of Gooznews on Health explains:

…Mary Claire King discovered that women in families with a history of breast cancer had common mutations of the BRCA1 and BRCA2 genes. But it’s important to remember that you can have the relevant mutations and not develop the disease.

Similarly, the National Cancer Institute explains the limitations of what can be known from a positive or negative test:

A positive test result generally indicates that a person has inherited a known harmful mutation in BRCA1 or BRCA2 and, therefore, has an increased risk of developing certain cancers… However, a positive test result provides information only about a person’s risk of developing cancer. It cannot tell whether an individual will actually develop cancer or when. Not all women who inherit a harmful BRCA1 or BRCA2 mutation will develop breast or ovarian cancer… Having a true negative test result does not mean that a person will not develop cancer; it means that the person’s risk of cancer is probably the same as that of people in the general population.

The Institute also recommends genetic counseling prior to testing in order to discuss the risks and benefits of such testing and the implications of a positive or negative result. The debate over whether over-the-counter genetic testing is appropriate without such counseling is likely, I think, to follow along similar lines as the debate over the elimination of required counseling for HIV testing since the availability of over-the-counter testing. Although the specifics and rationale are a little different, both discussions include a component of whether consumers can fully utilize or react to results without further counseling or intervention.

The bloggers at Genetic Future and Genomics Law Report have more.


3 Responses to “Debate Ensues on Over-the-Counter Genetic Testing”

  1. Eve Harris Says:

    HIV analogy is very limited: the virus is communicable; one’s DNA is not. Mathematically, genetics is more difficult to comprehend than infection. And the public health consequences are entirely different.

    However, neither viral infection nor genetic mutation = destiny.

    I’ve tried to blog about some of these rapidly changing-issues. For additional thoughts I recommend the Center for Genetics and Society, who write

    Genetic, reproductive and biomedical technologies have the power to promote or undermine individual well-being and public health, create private fortunes or advance the public interest, and foster or threaten a just and fair society.

    Used appropriately, many human biotechnologies hold great potential for treating disease and alleviating suffering. But these same tools can also be abused, either deliberately, inadvertently, or because of our inattention and inaction.

  2. Rachel Says:

    Eve, I completely agree that it’s a narrow/limited analogy, and do think the rationale/specifics are different, as stated – I’m comparing on only on the aspect of counseling in general, where for both types of testing there has been debate about whether it’s appropriate to take the test/get results absent some form of counseling. Thanks for your comment.

  3. Elaine Schattner, M.D. Says:

    I suspect many educated people overestimate the value of genetic information. In the 1990s, many scientists and doctors thought we’d solve diseases by uncoding our genetic sequences. It turns out that the genes we inherit determine just a small fraction of our health, due to epigenetic changes that affect how DNA is transcribed, environmental factors and other effects.

    For a healthy person, knowing if you have a particular gene variant – like BRCA1 or a mutation that disposes to hemochromatosis (an iron overload syndrome) – can be useful. But those tests are very few and are available, now through doctors’ offices and as individual tests. Learning that you have a variant gene that affects metabolism of a drug, like tamoxifen, seems useful only if you need to take that drug. Most of what’s sold, at several hundred dollars a pop, are very sketchy information about possible dispositions to disease.

    I think people should have the right to their DNA profiles if they want them. But the marketing’s a scam.

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