May We Scan Your Genome?

DNA is hip. At least that's what the new breed of genetic marketers would like you to believe. Last week, Navigenics, a California Web-based company, launched its $2,500 personalized DNA test—spit into a test tube and we'll tell you your risk for heart attack and other conditions—at a storefront in New York's trendy SoHo neighborhood. Computers, set against an orange and pink double helix, showed off Navigenics's Web site. Waiters circulated with pink cocktails—past a woman in a fur shrug over here, past Al Gore, a friend of the company (and partner in a firm that's invested in Navigenics), over there. Tony Bonidy, 60, from Pittsburgh, attended the much-publicized kickoff and wants to get himself and his family tested. "This is incredible," he said.

It's been 55 years since Watson and Crick defined the structure of DNA. Today, DNA is defining us. Most of the 1,100 genetic tests on the market are for rare single-gene diseases, like cystic fibrosis. But now, DNA-testing companies say they can scan our genomes and tell us our potential risk for diabetes, Alzheimer's and other common chronic conditions. Our DNA, once a mystery, is suddenly a commodity, and some two dozen businesses are competing for it in cyberspace. In January, another new company, 23andMe, handed out 1,000 free tests at the World Economic Forum in Davos, then boasted on its blog, The Spittoon, that "scholars, celebs and politicos swarmed" its booth. Featured photos: Naomi Campbell showing off her test kit, New York Times columnist Thomas Friedman spitting into his.

But what's the science behind all the hype? Direct-to-consumer (DTC) genetic-testing companies differ in their wares and the stringency of the research they rely on. DNA Direct, launched in 2005, offers diagnostic tests for individual disorders like hemochromatosis, or iron overload ($199). Most customers have family histories and want to know if they're at risk too, says CEO Ryan Phelan. Other companies sweep the genome more broadly. Navigenics scans nearly 1 million DNA snippets, then homes in on markers associated with 18 conditions, including multiple sclerosis and lupus—all of them influenced by multiple genes, many still unidentified. And then there's the entertaining stuff—23andMe ($999) and competitor deCODE Genetics ($985) provide gene tests not just for health conditions (alcohol flush reaction and lactose intolerance included), but for genetic ancestry as well.

With each new marketing push comes new criticism. Michael Watson, of the American College of Medical Genetics, says DNA testing doesn't belong in virtual clinics: "We're very concerned about the trivialization of genetics." One key issue is regulation. While the government mandates that genetic tests be performed in certified labs, not all are, and there's little to no oversight of a given test's accuracy or clinical usefulness. The individual gene variants linked to complex conditions may have only a modest effect on risk. And most DTC companies don't take lifestyle issues, like smoking, or family history into account, even though both can bump the odds up or down. There's plenty of debate, too, over the usefulness of information that can't be translated into action. Yes, you can cut out the fat and start jogging if your diabetes risk appears to be higher, but why pay hundreds of dollars to get that message?

Dr. Thomas Morgan, of the Washington University School of Medicine in St. Louis, worries that the business is getting ahead of the science. While researchers have clearly identified a chromosomal region linked to heart attack, for example, no single gene—including some being analyzed by DTC companies—stands out as the smoking gun. And undiscovered genes may turn out to be major risk factors. The result, says Morgan: "I might scare myself or reassure myself falsely based on the very limited knowledge that we have."

Market share, however, will not come to those who wait. "It's a matter of getting the field jump-started," says Dietrich Stephan, one of two scientists who founded Navigenics. The company, which offers genetic counseling, says its goal is improving health. Knowing your personal risk can lead to action, says CEO Mari Baker. Her genome scan found markers for celiac disease, a gluten allergy. A subsequent blood test came back positive. Now she avoids wheat, rye and barley. Most results won't lead to such clear-cut outcomes, though, and a recent report found that physicians are unprepared to deal with this wave of genetic information. Navigenics is offering a course for docs on Medscape to help fill the gap—a great way to market its product, too.

Andrew Meyer, 23, has caught the genome bug. Last December, he asked for donations on his blog, Buzzyeah.com, because he didn't have the cash. The $10s, $20s and $50s poured in. Meyer is still analyzing his 23andMe report, which he is sharing with the public. His motivation? "I'm really curious," he says. One day, no doubt, there'll be genetic tests for that, too.