A new study has found that direct-to-consumer genetic tests, like those marketed by 23andMe, Ancestry.com, Family Tree DNA, and MyHeritage, can be used to obtain inaccurate results.
The study, which was published by the diagnostics company Ambry Genetics in the journal Genetics in Medicine, casts some doubt on the testing methodologies of direct-to-consumer genetic tests, yet without calling out any specific companies in its paper.
Ambry, which processes DNA for doctors and research institutions, looked at variants that consumer test results identified that were associated with a risk of disease, and found that as many as 40 percent of those test results were false positives. In other words, a consumer test indicated that a troubling genetic variant was present in a person’s DNA, but when Ambry’s genetic sequencing lab analyzed samples from the same people, they found that it wasn’t.
Unlike clinical genetic tests that require a physician’s sign-off, direct-to-consumer tests are not meant to provide a diagnosis, and they offer risk information for only a limited number of conditions. If a consumer DNA kit uncovers a surprising or noteworthy genetic variant, the authors advise people to seek out doctor-ordered genetic tests to confirm the results.
