For years now, worried Americans have been able to glimpse their potential health future through genetic testing. And until recently, the nearly 1,000 genetic tests on the market have been available mainly through the mainstream medical establishment.
That means through clinics, hospitals and doctors' offices - and the tests have been cautiously interpreted for lay folks by trained genetic counselors.
But that is changing rapidly with the advent of direct-to-consumer, or DTC, genetic testing, a booming and controversial subset of the $6 billion genetic testing and molecular diagnostics business.
Because of its potential to mislead consumers - or at least waste their money - the DTC genetic testing industry is generating concern among doctors, patient advocates and, most recently, the Senate Special Committee on Aging. The panel held a hearing late last month tellingly titled, "At Home DNA Tests: Marketing Scam or Medical Breakthrough?"
"It's a buyer-beware marketplace now," said Gail Javitt, law and policy director of the Genetics and Public Policy Center at the Johns Hopkins University. "While the public believes genetic testing is subject to government oversight, that is largely not the case."
To those who market such tests, such as Ryan Phelan, chief executive and founder of DNA Direct in San Francisco, there's a huge benefit to being able to mail a DNA sample (a cheek swab or a few drops of blood) and get back a detailed analysis of your potential medical future.
The prospect is particularly attractive for patients so concerned about confidentiality that they don't want to be tested through their own doctors because the results would become part of their medical records - to which many people have access.
Moreover, genetic knowledge has increased so much in recent years, Phelan said, that many doctors don't have the time or expertise to do the tests. In the right hands - such as hers, she said - DTC testing can be done well.
At DNA Direct, there is a prescreening process to help consumers decide whether they really want testing. Clients who go ahead with tests get a consultation with a board-certified genetic counselor after they receive their 30 to 50 page report.
Dr. Fred Ledley, chairman of Natural and Applied Sciences at Bentley College in Waltham, Mass., and founder of several "personalized medicine" companies, also welcomes DTC genetic testing as "the way of the future."
"What people really want to buy is privacy and control over information," he said.
But others are far less sanguine, in part because government regulation of these tests is so loose. Consumers who arrange for tests over the Internet risk being sold "personalized" products - such dietary supplements, cosmetics or even exercise programs - that are not personalized at all, critics say. They risk spending hundreds to thousands of dollars for generic medical advice, such as "stop smoking," that they can easily get elsewhere free.
More importantly, unless test results are interpreted by a trained genetic counselor, consumers risk getting misinformation, said Dr. Jeff Milunsky, director of Clinical Genetics at the Boston University School of Medicine Center for Human Genetics.
For example, there are hundreds of mutations in two well-known breast cancer genes, BRCA1 and BRCA2, for which reliable commercial tests exist. A woman could be told that she doesn't have the common mutations, but might still be a high risk from less-common mutations or a different risk gene altogether, he said.
The Federal Trade Commission watches out for false advertising claims, but it has not been aggressive on DTC genetic testing, said Javitt. Thanks to a law called the Clinical Laboratory Improvement Amendments of 1988, the government regulates the laboratories that conduct the genetic testing, but the law does not address the clinical validity of the tests.
Only about a dozen genetic tests have been reviewed and approved by the Food and Drug Administration, according to a July 27 report to the Senate by the Government Accountability Office.
The FDA considers a genetic test to be a regulated "medical device" only if it is manufactured as a freestanding kit and sold to a lab. Most genetic tests - including those used by mainstream labs - are manufactured by in-house clinical laboratories. In those cases, the lab decides whether the test actually measures what it purports to measure.
To see how DTC tests may impact buyers, GAO investigators purchased four tests over the Internet and supplied the testing companies with 12 DNA samples taken from one 9-month-old girl and an unrelated 48-year-old man, but that were described as coming from multiple people.
The results, in some cases, were laughable. One site claimed that its expensive dietary supplements could repair DNA damage, which no pill has been shown to do. Others offering supposedly "personalized" results that told smokers to quit and nonsmokers to continue to abstain.