FDA Clearance of DTC Genetic Test Gets Mixed Reviews
On February 19, the US Food and Drug Administration (FDA)authorized 23andMe to market a direct-to-consumer (DTC) carrier test for Bloom syndrome. The agency's decision to classify such carrier screening tests as class II medical devices, and exempting them from premarket review, may pave the way for a return of DTC genetic testing. The decision and the open door, however, have garnered mixed reviews from genetic counsellors and clinicians.
"This is the first step in our commitment to returning health information to our customers. Because this process was successful, we may be able to submit some future submissions through the standard 510(k) pathway," a spokesperson for 23andMe, based in Mountain View, California, told Medscape Medical News.
FDA had banned the company from DTC marketing of genetic tests with a warning letter sent November 22, 2013, claiming that their "Personal Genome Service," termed "information," violated the Federal Food, Drug and Cosmetic Act. The company was selling the service without submitting evidence of accuracy, reliability, and clinical meaning.
Pros and Cons of DTC Genetic Testing
Genetics professionals had mixed reactions to the news.
"The greater impact is not in returning carrier testing for Bloom syndrome specifically, but in laying the framework for reporting carrier status of all single gene recessive conditions," said Joshua Petrikin, MD, director of Neonatal Genomics at the Center for Pediatric Genomic Medicine at Children's Mercy Kansas City, Missouri. "This is a useful step in empowering consumers with knowledge of their genetic predispositions and beneficial as a starting place for patients' discussions with their physicians."
Joy Larsen Haidle, MS, president of the National Society of Genetic Counselors and genetic counselor at the Humphrey Cancer Center in Minneapolis, Minnesota, disagreed. "This new policy is a slippery slope and might unwittingly set a dangerous precedent. Why not just add a bunch of other genes? Genetic testing is not a one-size-fits-all option," she toldMedscape Medical News.
Leading up to the February 19 announcement, FDA required 23andMe to conduct multiple tests of accuracy and for the ability of consumers to understand the instructions and collect saliva samples. If the product is offered over-the-counter, labels on test kits must explain what results mean and provide information for contacting a genetics professional.
Robert Marion, MD, pediatrician and chief of the Division of Genetics at The Children's Hospital at Montefiore and developmental pediatrician at the Albert Einstein College of Medicine, New York, New York, has concerns that packaging requirements are not enough. "There's a reason entire fields, like genetic counseling and clinical genetics, have grown up over the past 50 years: genetic testing is not a simply 'black-or-white' issue of yes, you are a carrier of this mutation or no, you are not a carrier."
For example, Dr Marion pointed to interpretation of results, informing relatives, and misunderstanding as areas of potential concern.
Even some physicians have little experience with genetic testing, he said, relating the case of a couple considering terminating a pregnancy because one of the partners was found to be a carrier for Tay-Sachs disease. "Neither the obstetrician who ordered the test nor the couple understood that in order to have a child with Tay-Sachs, both parents needed to be carriers. Testing without the involvement of a professional is going to cause problems."