Until recently, the nearly 1,000 genetic tests on the market have been available mainly through the mainstream medical establishment -- clinics, hospitals, and doctors' offices. The results have been cautiously interpreted for lay folks by trained genetic counselors.
But that is changing rapidly with the advent of direct-to-consumer 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 direct-to-consumer genetic testing industry is generating concern among doctors, patient advocates, and, most recently, the US Senate Special Committee on Aging, which 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 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, like Ryan Phelan , CEO and founder of DNA Direct in San Francisco, there's a huge benefit to being able to mail off a DNA sample (a cheek swab or a few drops of blood) and get back a detailed analysis of your potential medical future. This is particularly true for patients who are so concerned about confidentiality that they don't want to get 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 exploded 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 -- like hers, she said -- direct-to-consumer testing can be done well. At DNA Direct, there is a prescreening process to help consumers decide whether testing is for them and a free consultation by phone with a board-certified genetic counselor after customers receive their 30- to 50-page report.
Dr. Fred Ledley , professor and chairman of natural and applied sciences at Bentley College in Waltham and founder of several ``personalized medicine" companies, welcomes direct-to-consumer genetic testing as ``the way of the future. What people really want to buy is privacy and control over information."
But others are far less sanguine, in part because government regulation of these tests is so loose. Consumers going the Internet route risk being sold ``personalized" products -- like dietary supplements or cosmetics or even exercise programs -- that are not personalized at all. They risk spending hundreds to thousands of dollars for generic medical advice -- ``Stop Smoking ," for example -- that they can easily get elsewhere free.
More important, unless test results are interpreted by a trained genetic counselor, people risk getting misinformation, said Dr. Jeff Milunsky , director of clinical genetics at the Boston University School of Medicine's 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 didn't have the common mutations but might still be at high risk from less common mutations or a different gene altogether, he said.
In general, tests like BRCA1 and BRCA2 are recommended for women with a family history of the disease. And, as with all medical tests, there is a risk for error.
The Federal Trade Commission does watch out for untruthful advertising claims but has not been aggressive on direct-to-consumer 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 themselves. Indeed, only about a dozen genetic tests have been reviewed and approved by the US Food and Drug Administration, according to a report to the Senate committee on July 27 by the Government Accountability Office .
To see how direct-to-consumer tests impact buyers, GAO investigators purchased four tests through the Internet and supplied the testing companies with 12 DNA samples -- actually taken from one 9-month old girl and an unrelated 48-year old man, but described as coming from multiple people.
The results, in some cases, were laughable. The nine samples sent from the baby girl received a variety of different recommendations. If the government pretended the sample was from someone who smoked, the recommendation was to stop smoking. In particular, the GAO cautioned against tests that purport to tell, by a sample of DNA, that the consumer should buy ``personalized" dietary supplements that could cost $1,200 a year when the same ingredients could be purchased at a local store for $35 a year.
Despite such concerns, the market for all types of genetic testing is likely to soar. A Harris poll in 2002 showed that 80 percent of adults think genetic testing is a good thing and half said they would want a test for a serious medical condition even if there were no way to prevent or treat it. The poll also indicated that people are willing to spend hundreds of dollars out of pocket to get genetic tests.
Given that demand, the big issue, said Kelly Ormond , immediate past president of the National Society of Genetic Counselors, will be making sure that consumers get the right tests, that the tests are valid, and that results are interpreted by trained genetic counselors.
That's a tall order because there are only 2,000 to 3,000 trained genetic counselors in the United States -- who typically have a master's degree -- plus 1,500 or so physicians and some nurses who specialize in genetics.
And that, said Ormond, means that consumers who opt for the direct-to-consumer genetic testing must be extra savvy. Before handing over your credit card number, ask the company what its test means -- will it show whether you have a clear susceptibility to a certain disease or just a pattern of clues that may or may not be meaningful? Are there data to show that you will get sick later in life if you have a ``bad" gene or is that gene just one of many risk factors?
Think carefully about the privacy issue. If you are truly at risk for a serious disease, chances are you'll see a doctor, and that information will wind up in your medical record anyway. And if you are asked by an insurance company if you've had such a test and you answer ``no," that would be fraud.
Judy Foreman is a freelance columnist who can be contacted at email@example.com.