WASHINGTON, D.C.--Dozens of companies these days are hawking genetic testing kits, which claim to give consumers a glimpse of their future health. But how accurate are they? Perhaps not very, according to witnesses at U.S. Senate hearing here today, as well a report released concurrently by the Government Accountability Office (GAO), Congress's investigation arm.
There are genetic tests for more than 1000 conditions. While in some cases, such as cystic fibrosis, having a particular set of mutations all but guarantees disease, in many others it correlates only with an increase in disease risk. For example, mutations in the BRCA1 and BRCA2 genes correspond with a roughly 50% to 80% risk of breast cancer. DNA tests are regulated by the Clinical Laboratory Improvement Amendments (CLIA), which, some critics have charged, lacks the ability to effectively oversee complex and rapidly changing diagnostics.
While most DNA tests are administered in a doctor's office, some can be ordered from companies online. A subset of these tests, called "nutragenic" DNA tests, claim to provide consumers with information about diseases for which they're supposedly at risk as well as, in some cases, dietary advice--such as pills sold by the company--that may counter the hazard.
It's this class of tests that GAO and the Senate's Special Committee on Aging tackled. To conduct the investigation, the GAO team ordered DNA tests online, all of which examined between four and 19 genes, from four companies: Market America, Genelex, Sciona, and Suracell. Using DNA samples from a 48-year-old man and the 9-month-old daughter of GAO's Gregory Kutz, who helped assemble the report, the team created 14 fictitious characters with various lifestyles.
If the companies were truly focusing on genetics, many of the results that came back didn't make sense. In some cases, two DNA samples from the same source came back with a different list of disease risks. In addition, the companies recommended nutritional formulas tailored to an individual's DNA--but the investigators found that identical formulas were prescribed for people with different DNA.
The DNA tests "threaten more than the public's pocketbook; they threaten public health," Kathy Hudson of the Genetics and Public Policy Center testified at the hearing. Hudson told the senators that legislation was needed to better regulate and validate these tests. Representatives from the companies, however, took a different view. Rosalynn Gill-Garrison, the chief science officer of Sciona, based in Boulder, Colorado, emphasized that her firm's products were safe, effective, and ethically appropriate.