US federal agencies don't regulate consumer tests for genetic disorders.

Have a few hundred bucks to spare? You could order a genetics test and check whether your kids are really yours, whether your diet matches your DNA and whether you or your future children are at risk for breast cancer.

But there is no guarantee that you'll actually understand the results. Experts say few genetic tests on the market explain the huge chasm between the genotype they can confirm and the physical manifestation of the genes. The tests are also largely unregulated and can vary wildly in quality.

The latest to join the market is a controversial set of tests manufactured by San Francisco–based DNA Direct to check potential reasons for infertility and multiple pregnancy loss. The company's website directs customers to a local blood collection center. A contracted laboratory then tests for disease genes—such as those associated with cystic fibrosis or fragile X syndrome—based on the customers' self-reported risk factors, and sends the results to DNA Direct. The company then attaches a packet of supporting materials and posts it online for the customers.

The FDA hasn't done much. There are no other evidence-based reviews. We hope to fill that gap. , Muin Khoury, CDC Office of Genomics and Disease Prevention

Genetic counselors are available by phone, but Jennifer Graham, director of product development for DNA Direct and one of two genetic counselors on staff, says the number of people who call is “remarkably low.”

Companies have been expanding their range from paternity tests to genetic diseases in the past three years but, apart from requirements for lab standards, the tests are unregulated. The US Food and Drug Administration (FDA) may have jurisdiction over the tests in some circumstances—if the tests are sold as kits or use certain reagents, for instance. But most DNA testing is done with 'homebrew' tests that the FDA has not attempted to regulate.

The Secretary's Advisory Committee on Genetics, Health, and Society, under the US Department of Health and Human Services, has taken on the matter, albeit at a glacial pace. Established in 2003, the committee began examining the topic a year ago; it is set to meet with FDA officials in June to discuss assigning responsibility for regulating the field.

In the meantime, the US Centers for Disease Control and Prevention has also convened a panel to examine the tests. “The FDA hasn't done much,” says Muin Khoury, director of the agency's Office of Genomics and Disease Prevention, whose panel is set to meet in May. “There are no other evidence-based reviews. We hope to fill that gap.”

The problem with most of these tests, critics say, is that even those that are widely used give results that are hard to interpret.

For instance, many outfits sell tests for the breast cancer susceptibility genes BRCA1 and BRCA2, but the significance of the results is far from simple, notes Kelly Ormond, president of the National Society of Genetic Counselors. Even if a disease-linked gene is present, she says, it would be important to know whether the gene carries mutations that confer risk.

Gail Javitt, a policy analyst at Johns Hopkins University's Genetics and Public Policy Center, says regulators at the various agencies need to put their heads together and make genetic testing a priority. “A clearer direction of oversight needs to be given either by [the Department of Health and Human Services] or Congress,” she says. “Whether it will happen remains to be seen.”