Genetic Testing Goes Mainstream

People clearly approve of DNA testing. In a recent Prevention.com poll, 87% of respondents said they'd want to know which genetic diseases they're at high risk of developing. Moreover, 54% said they'd be likely to have a genetic test even if there was no known treatment or way to prevent the disease.

Plenty of companies are eager to meet this demand, selling at-home tests that range in cost from hundreds to thousands of dollars. Some offer tests that have long been available through doctors and genetic counselors--for instance, those that check for BRCA 1 or 2, the genes linked to a small percentage of inherited cases of breast cancer. Newer versions look at your SNPs (pronounced snips, short for "single nucleotide polymorphisms"), the slight variations within DNA that can account for differences in appearance and how we develop genetic diseases. The companies don't predict that you're going to get, say, cancer or macular degeneration. Rather, you get back a report showing the risk you run, compared with the average person. One of the newest entrants into the at-home arena, Navigenics, recently launched its $2,500 HealthCompass test, which looks for markers associated with 23 common conditions--including diabetes, prostate cancer, and Alzheimer's disease--that are "actionable," or able to be prevented or detected early. For an additional $250 per year, subscribers receive personalized updates when relevant genetic research--for instance, the discovery of new SNPs--changes their health outlook.

Health-conscious consumers are clearly enamored with these high-tech tests--they're expected to spend an estimated $6 billion to have their DNA decoded over the next 5 years. But while the business of do-it-yourself DNA testing is booming, experts say this new frontier of medicine isn't ready for prime time. They worry that the field is insufficiently regulated, not all of the tests are reliable, and the information garnered is incomplete and possibly misleading. "Some tests lack adequate scientific evidence to support their use, and the lack of regulation means there's no way for consumers to separate the good from the bad," says Gail Javitt, law and public policy director for the Genetics and Public Policy Center at Johns Hopkins University.