DNA tests that consumers buy online to find out whether they carry genes for certain diseases are misleading, lack predictive value and can exploit the public by recommending pricey dietary supplements based on the test results, an official for the Government Accountability Office (GAO) told lawmakers yesterday.
Consumers can receive their genetic test results from labs with “home-brew” kits, which the GAO says have minimal federal oversight. The test results provide customers with dietary and exercise information to address their genetically determined health risks such as diabetes and heart disease, without consulting a doctor.
The report comes after a yearlong GAO investigation ordered by Sen. Gordon H. Smith, Oregon Republican and chairman of the aging committee.
“Buyer beware,” Mr. Smith said during a committee hearing yesterday. “I am deeply disturbed by GAO’s findings.”
GAO investigators bought tests from four genetic testing Web sites, including Market America, Genelex, Sciona and Suracell. After collecting cheek swabs from an unrelated man and woman, they used the DNA samples to create profiles of 12 fictitious consumers with different age and lifestyle descriptions.
But the Web sites found different results for each profile.
“If the recommendations were truly based on genetic analysis, then the nine fictitious consumers that GAO created for these sites using the female DNA should have received the same recommendations because their DNA came from the same source. Instead, they received a variety of different recommendations, depending on their fictitious lifestyles,” the GAO report said.
The results used “ambiguous language” to describe a genetic profile, such as having a “damaged gene,” said Gregory Kutz, managing director for GAO’s forensic audits and special investigations. None of the results’ predictions can be medically proven because scientists do not know enough about gene interaction causing certain diseases, he said.
Finally, some of the Web sites recommend that customers buy expensive supplements and may interfere with a particular heath condition, he said.
Administrators of the Web sites testified yesterday their services encourage customers to seek a medical professional to interpret the results.
Also, the Web sites are providing a valuable tool for the average consumer, said officials with the laboratories that perform the tests.
“By understanding genetic variation and its relationship to drug response, it is possible to determine which individuals are most likely to benefit from a given drug, even before the drug is prescribed,” said Carol Reed, chief medical officer for Genaissance Pharmaceuticals in Newton, Mass.
But administrators and laboratory officials said they favor more regulation for genetic testing.
The federal government has a “regulatory gap” for the testing, said Kathy Hudson, director of the Genetics and Public Policy Center at Johns Hopkins University’s Berman Bioethics Institute, who also testified yesterday.
Measures created by the Centers for Medicare and Medicaid Services in 1988 do not provide enough federal oversight for genetic testing and the agency must create guidelines, she said.