The FDA has approved the Bloom Syndrome carrier test from 23andMe, Mountain View, Calif, a direct-to-consumer (DTC) genetic test to determine whether a healthy person has a variant in a gene that could lead to their children inheriting the serious disorder.
The agency is also classifying carrier screening tests as class II, and intends to exempt these devices from FDA premarket review, which creates the least burdensome regulatory path for autosomal recessive carrier screening tests with similar uses to enter the market.
"The FDA believes that in many circumstances it is not necessary for consumers to go through a licensed practitioner to have direct access to their personal genetic information. Today's authorization and accompanying classification, along with FDA's intent to exempt these devices from FDA premarket review, supports innovation and will ultimately benefit consumers," says Alberto Gutierrez, PhD, director of the Office of In Vitro Diagnostics and Radiological Health in the FDA's Center for Devices and Radiological Health.
In general, carrier testing is a type of genetic testing performed on people who display no symptoms for a genetic disorder but may be at risk for passing it on to their children. A carrier for a genetic disorder has inherited one normal and one abnormal allele for a gene associated with the disorder. A child must inherit two abnormal alleles, one copy from each parent, in order for symptoms to appear.
No test is perfect. Given the probability of erroneous results and the rarity of these mutations, professional societies typically recommend that only prospective parents with a family history of a genetic disorder undergo carrier screening. For example, when a gene mutation is expected to be very rare, a positive result for the mutation may have a high probability of being wrong.
Like other home-use tests for medical purposes, the FDA requires the results to be conveyed in a way that consumers can understand and use. This is the same approach the FDA has taken with other over-the-counter consumer products such as pregnancy, cholesterol, and HIV tests for home use.
While the FDA is not limiting who should or should not use these tests, it is requiring that the company explain to the consumer in the product labeling what the results might mean for prospective parents interested in seeing if they carry a genetic disorder.
If sold over the counter, the FDA is also requiring 23andMe to provide information to consumers about how to obtain access to a board-certified clinical molecular geneticist or equivalent to assist in pre- and post-test counseling.
The test is intended only for postnatal carrier screening in adults of reproductive age, and the results should be used in conjunction with other available laboratory and clinical information for any medical purposes.
23andMe previously marketed a Personal Genome Service in the United States, but it ceased providing direct health information to US consumers after the FDA issued a 2013 Warning Letter. The letter directed the company to stop selling the product because of failure to obtain marketing clearance or approval to assure their tests were accurate, reliable, and clinically meaningful.