FDA has authorized marketing of Bloom Syndrome carrier test, a direct-to-consumer genetic test from 23andMe.The test is designed to identify healthy individuals who carry a gene that could cause Bloom Syndrome in their offspring.
FDA has authorized marketing of Bloom Syndrome carrier test, a direct-to-consumer genetic test from 23andMe.The test is designed to identify healthy individuals who carry a gene that could cause Bloom Syndrome in their offspring.
Bloom syndrome is a rare disorder that is more common in people of Central and Eastern European, or Ashkenazi, Jewish background. One in 107 people of Ashkenazi Jewish descent are carriers for Bloom syndrome. The disorder is characterized by short stature, sun-sensitive skin changes and an increased risk of cancer. According to the National Institute of Health, this condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations.
Along with this authorization, FDA is also classifying carrier screening tests as class II. In addition, FDA intends to exempt these devices from FDA premarket review. The agency plans to issue a notice that announces the intent to exempt these tests and that provides a 30-day period for public comment. This action creates the least burdensome regulatory path for autosomal recessive carrier screening tests with similar uses to enter the market.
“This is a major milestone for our company and for consumers who want direct access to genetic testing,” Anne Wojcicki, 23andMe CEO and co-founder, said in a press release. “We have more work to do, but we remain committed to pursuing a regulatory path for additional tests and bringing the health reports back to the US market.”
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 1 normal and 1 abnormal allele for a gene associated with the disorder. A child must inherit 2 abnormal alleles, 1 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.
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Similar to other home-use tests for medical purposes, FDA requires the results to be conveyed in a way that consumers can understand and use. This is the same approach FDA has taken with other over-the-counter consumer products such as pregnancy, cholesterol and HIV tests for home use.
While 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, 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.
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23andMe performed 2 separate studies to demonstrate that their test is accurate in detecting Bloom syndrome carrier status. One study conducted at 2 laboratories tested a total of 123 samples, including samples from known carriers of the disease. An additional study evaluated 105 samples at 2 additional laboratories. Both studies showed equivalent results in detecting carrier status of Bloom syndrome when the same samples were tested.
The company also conducted a usability study with 295 people not familiar with the 23andMe saliva collection device to demonstrate consumers could understand the test instructions and collect an adequate saliva sample.
Finally, the company conducted a user study of 302 randomly recruited participants representing the US general population in age, gender, race and education level to show the test instructions and results were easy to follow and understand. In all the studies, more than 90% of participants indicated they understood the test results.
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 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.