Dec 2 2007
Direct-to-consumer advertising for commercial genetic testing is on the rise and may be problematic, according to a Massachusetts General Hospital (MGH) physician. In the December issue of Obstetrics & Gynecology, Erin Tracy, MD, MPH, warns that such testing is poorly regulated and may present potential pitfalls for patients and physicians.
“Some of the tests that are being offered have no proven clinical validity whatsoever and are quite costly,” says Tracy. “So patients spend money trying to identify a particular gene to figure out if their child is prone to addictive behavior, for example. If the test comes back positive, parents are often not adequately counseled as to what those results might mean, whether these tests have any proven value, or what resources are available for follow up."
The majority of DNA tests are “home brews” that are unregulated by the FDA, Tracy explains. While the FDA needs more funding to regulate genetic testing, it also is limited in its ability to regulate services based in other countries. According to a 2002 study in Genetics in Medicine, 24 of 105 web sites offering genetic testing directed potential clients to international mailing addresses. Many sites listed professional societies or accrediting organizations on their pages, implying sponsorship or approval of their activities that may not be accurate.
Like other direct-to-consumer ads, these materials do not need to be reviewed by the FDA before they are published. Many involve emotional appeals – such as placing an ad for a cancer-associated gene test in the program of a play about a woman dying from ovarian cancer – instead of clear discussion of the rationale for screening. Results of genetic tests have the potential to cause excessive alarm or to falsely assure consumers that they will not develop cancer or disease. Direct-to-consumer advertising for genetic tests may also give the erroneous impression that a certain test is mandatory.
“Some patients with no risk factors for breast cancer come in and request the test for BRCA-1 and BRCA-2 mutations,” says Tracy, referring to a recent advertising campaign. “The ads are compelling and they're emotionally driven. I end up spending time discussing why a particular test being advertised is not appropriate when I should be addressing important issues such as eating a healthy diet or smoking cessation.” At the same time, she notes, without proper counseling a patient who does not have the BRCA-1 or BRCA-2 mutations might assume she has no risk for breast cancer and forgo recommended mammograms and clinical breast examinations.
In order to make an informed decision about genetic tests, patients should consult with their physicians about their particular risk for cancer or other diseases, Tracy says. “Before any test is ordered, there should be a thought process about whether that particular test is appropriate and what we'll do with it. And physicians need to stay current about what's out there so we can best advise our patients.”