As direct-to-consumer genetic testing companies like 23andMe only analyze small portions of customers' DNA, some consumers upload their raw data to third-party sites to diver deeper into their genetic makeups, but the New York Times reports that sometimes those findings aren't accurate.
After getting his 23andMe report, Joshua Clayton, a radiology resident at Baylor University Medical Center in Dallas, tells the Times that he then uploaded his raw data to Promethease, which does a deeper analysis. That analysis told Clayton that he harbored a Lynch syndrome mutation — but when he sought confirmation testing by a clinical lab, he was told he did not actually have that mutation, the Times says. Genetic counselors and others are also concerned about people who are told the opposite: that they have no disease-linked mutation when they truly do, it adds.
23andMe tells the paper that it warns customers that the raw data they provide shouldn't be used for medical or diagnostic purposes and Promethease adds that it, too, warns users that their analysis isn't a medical diagnosis and to seek a clinically validated test if they find a worrisome variant.
Clayton tells the Times that with his medical background, he was fairly savvy about the tests' limitations, but "that didn't change the frightened feelings or concern." He also adds that others might not have known, as he did, how to seek follow-up clinical testing.