Ever wonder why your hair is the color it is, where your remote ancestors resided, or whether you carry genes for diseases that could affect you or your children?
As of today, it’s not possible to know all of that with certainty — not even close. But you can get a few answers by sending a saliva sample to a private company and paying it to analyze your DNA. Even better, as new research becomes available, you can check it against your personal data; some companies even provide subscription services that do the legwork for you. It is a true scientific revolution — the collected data inform people about their history, help doctors and patients make medical decisions, and enable researchers (with permission from their subjects) to make headway in the nature–nurture debate. As prices fall — already, Google-backed 23andMe, one of the leading companies, provides its service for a mere $200 plus $5 a month — progress will only accelerate.
And so, naturally, the Food and Drug Administration is preparing to step in with heavy regulations. The “test kits” — spit receptacles, more or less — that these companies send to their customers apparently qualify as “medical devices,” and thus place the process in the FDA’s jurisdiction. The FDA already regulates the labs that do the actual testing, but now it is considering — with input from a recent advisory panel and urging from the American Medical Association — additional limits on any information containing “medical claims.” Most troubling, it may require prescriptions for many DNA tests, or mandate that consumers pay physicians or “genetic counselors” to explain their results to them.
It is easy to oversell DNA testing, especially when it comes to medical benefits, and some companies fail to resist the temptation. In the interest of preventing fraud, the FDA might reasonably place limits on the claims that these companies make. But there is no reason to insist that a government-approved doctor stand between Americans and their DNA.
WHAT DNA CAN’T TELL YOU
Anyone considering direct-to-consumer (DTC) testing for medical reasons should know the technology’s limits. “For maybe 10 percent of people, the medical information is very actionable, very predictive,” says Razib Khan, who writes about genetics for the Discover magazine blog Gene Expression, and who has been genotyped by 23andMe. Jon Entine, a fellow at the American Enterprise Institute, for example, discovered he had a mutation that raises the risk of breast cancer — information that is quite important, given that his daughter might have inherited the gene. But for most people — except those who don’t have access to their family’s medical history (adoptees, for instance) — a genetic test is unlikely to contain much unexpected medical information.
After all, the results won’t tell you whether you’ll get leukemia; they’ll tell you whether you’re at an elevated risk for leukemia, which you already know if leukemia runs in your family. And the numbers can be misleading. Khan notes that if you’re 50 percent more likely than the average person to get a certain disease, that may not be cause for concern: You could have gone from a 1 in 500 chance to a 1 in 333 chance. “You need a fine-grained understanding of probability to get the most juice from it,” he says, “and there’s not much juice there to begin with.”
DTC companies usually provide some kind of disclaimer to this effect, but some ad copy can leave the opposite impression. Iceland’s deCODEme, for example, says that “your genes are a road-map to better health” and that you can “discover your genetic risk for 47 diseases and traits ranging from Heart Attack and Diabetes to Alcohol Flush Reaction and Testicular Cancer.” These kinds of borderline-untrue statements — genes can bepart of a roadmap to better health; you can see data on the genetic risk factors that happen to have been discovered already — are par for the course in advertising, but they could easily be misinterpreted by uninformed shoppers.