Another news magazine covered emerging health issues at the beginning of the new year. U.S. News and World Report had an article titled, "Unraveling Your DNA's Secrets." This article provides a relatively in-depth discussion of genetic testing, including the results of their independent test of genetics tests available online.
To investigate the quality and usefulness of direct-to-consumer genetic tests, U.S. News tried six of them. Three were the same type of tests used by doctors for celiac disease, hemochromatosis, and breast cancer. Three others–for Alzheimer's disease, depression, and glaucoma and macular degeneration–test genes associated with the diseases but aren't used in medical practice. Our testers were U.S. News staff members and their relatives. One staffer took a DNA sample from his 3-year-old dog, Tate, a corgi mix. We found that the value in diagnosing or predicting disease varies widely. Some could be helpful in making health decisions, while others could be worthless or even dangerous. And it's often hard to tell which is which. Our key findings:
Some tests that promise to reveal the risk of disease rely on genes that aren't up to the task. The gene tested for Alzheimer's disease, for example, indicates only increased susceptibility. And there's nothing people can do to reduce that risk.
The advice some testing firms offer patients with the results can be misleading. The test results often overstated the risk of disease or were unclear about how to interpret that risk. References to scientific research included with some of the results were outdated or irrelevant. Several tests offered generic preventive advice, such as "get regular exercise." Just two companies, DNA Direct and Denver's Kimball Genetics, offered access to certified genetic counselors trained to interpret and explain the results. Experts in the field say that interpretation is crucial because the results are usually not black and white.
Direct-to-consumer genetic tests are not regulated. The FDA does not evaluate the safety and efficacy of at-home genetic tests. Some are done in certified laboratories used by doctors and hospitals; others are not. In July, the Federal Trade Commission urged consumers to be wary of the claims of DTC genetic testing.
If you're a regular Genetizen reader, you will not find their findings surprising. But, you may want to read the rest of the article anyway. If the findings are news to you, check out the Genetizen archive as well as the U.S. News article.
Marie Godfrey, PhD