On November 22, the US Food and Drug Administration sent a letter to the direct-to-consumer genomics company 23andMe. 23andMe is well-pedigreed startup with at least $161 million of funding from Google and other leading technology investors. Their service offers a personal genetic analysis that promises to “find out if your children are at risk for inherited conditions, so you can plan for the health of your family.”

In their letter, the FDA takes aim precisely at these types of claims: “to date, 23andMe has failed to provide adequate information to support a determination that the PGS (23andMe’s Personal Genome Service) is substantially equivalent to a legally marketed predicate for any of the uses for which you are marketing it.” The FDA is calling into question both the accuracy and reliability of the data produced by 23andMe’s genetic analysis, expressing concern that a misinterpretation of the results could lead to very real negative health outcomes. The FDA cites the potential for false positives — which could lead to patients undertaking unnecessary or potentially dangerous treatments — and false negatives, which could result in a patient ignoring a potentially fatal disease.