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April 3, 2008 -- Firms use misleading claims to sell genetic tests to patients, and federal authorities should crack down, Johns Hopkins researchers say.
Several companies market genetic tests directly to consumers over the Internet. For a price, they'll send you a kit, you swab your cheek or spit in a sample jar and send it back, and they'll test your DNA. Test makers offer all kinds of information about what your genes say about things like your ancestry, paternity, and nutrition.
They also offer to tell how well a large number of prescription drugs will work -- or not work -- for you. That's a misleading claim, suggests a Science editorial from Johns Hopkins' Genetic and Public Policy Center.
"We think consumers ought to be able to have confidence in the tests that are out there -- that they are performed accurately and provide information that promotes health," editorial co-author Gail Javitt, JD, MPH, law and policy director the center, tells WebMD. "Right now we have genetic tests that impede that goal."
If that's true, why don't the FDA and the Federal Trade Commission (FTC) take action against the companies?
"Consumers should be aware of the lack of oversight of these tests," Javitt says. "From our public-opinion research, consumers expect and believe these tests are regulated by government agencies. But these expectations and beliefs are not supported by the facts."
Javitt and colleagues call for FDA regulation -- and for FTC enforcement action if marketers are deemed to have made false claims.
One of the firms the editorial singles out for criticism is the Seattle firm Genelex, which offers directly to consumers a wide variety of genetic tests on its web site.
"I don't believe we have any unsupported claims on the web site," Genelex CEO Howard Coleman tells WebMD. "There is all this talk about personalized medicine, but some of this genetic testing is very underutilized. We have been doing this since 2000, clearly ahead of the marketplace."
Javitt and colleagues point to a specific example of why they feel genetic testing must be regulated. Genelex, they note, offers to test patients for specific genetic mutations that affect liver enzymes. These CYP enzymes determine how quickly the body processes a number of drugs -- including the SSRI class of antidepressants.
Genelex offers not only to test for enzymes that affect SSRI processing, but also to interpret the test results. Although the web site clearly states that these interpretations are intended as an aid to patients' doctors, the results are provided directly to the patient who pays for them.
The Genelex site makes specific claims about the types of information genetic testing CYP will provide -- such as proper dosage and drug interactions.
Yet a January 2007 review of CYP tests for SSRI sensitivity -- by the CDC's EGAPP (Evaluation of Genomic Applications in Practice and Prevention) working group -- found the test wasn't ready for prime time. Alfred O. Berg, MD, MPH, professor and chairman of the family medicine at the University of Washington, chairs the EGAPP working group.