By Diane Allingham-Hawkins, PhD, FCCMG, FACMG, Senior Director, Genetic Test Evaluation Program and Technical Editing
In a letter dated November 22, 2013, the Food and Drug Administration (FDA) ordered the direct-to-consumer (DTC) genetic testing company, 23andMe, to immediately stop marketing the company’s Personal Genome Service (PGS) until the FDA authorizes the use of the test as a medical device. You can read the full text of the letter here.
At issue is the fact that tests such as the PGS, which consumers can order over the Internet without the involvement of a healthcare provider, purport to provide information relevant to the health of the individual being tested. In 2010, the FDA issued letters to a number of DTC genetic testing companies after Pathway Genomics announced it would be selling its DNA collection kits through Walgreens. In the original group of letters, the FDA indicated that they considered DTC genetic tests to be medical devices that required regulatory approval before they could be marketed but stopped short of requiring the tests to be taken off the market. In March 2011, the FDA held an advisory committee meeting on consumer genomics. According to one attendee, the meeting focused largely on the scientific integrity of DTC genetic tests and the significant challenges of validating polygenic genetic risk assessment, which is the basis of most DTC genetic tests.
To date, only 23andMe has sought FDA clearance through the 510(k) process. However, in the strongly worded letter of November 22, 2013, the FDA indicated that 23andMe had failed to address key issues related to analytical and clinical validity raised months ago by the FDA and that the agency now considers the 510(k) submissions withdrawn. The letter points out that although 23andMe has not communicated with the FDA since May 2013, the company has recently begun television marketing of the PGS, indicating that they plan to “expand the PGS’s uses and consumer base without obtaining marketing authorization from the FDA.” It should be noted that, as of today, 23andMe continues to market the PGS on their website.
I submitted my DNA to be tested using the 23andMe PGS, as well as the now defunct Navigenics Health Compass. The 2 tests were quite different with respect to the health conditions being tested for and other tests included. There was overlap, however, for 24 health conditions and 7 pharmacogenetic tests, which allowed for direct comparisons. Two thirds of the time, my results were concordant between the 2 tests in that both tests similarly predicted a higher-than-average, average, or lower-than-average risk. What was interesting was that what was considered to be an average risk figure differed between the 2 tests, sometimes by as much as fourfold! For example, 23andMe used an average risk figure for heart attack of 7.4% while Navigenics used 25% as the average risk. For the remaining one third of health conditions, my results were discordant between the 2 tests. For example, while 23andMe predicted a lower-than-average risk for atrial fibrillation, Navigenics gave me a higher-than-average risk. As a geneticist, I have the training and expertise to understand that these tests are not based on rigorous science and therefore should be considered recreational at best. Sadly, it is easy to see, however, how the results may be misinterpreted by patients and non-genetics health professionals, leading to potential harm. The FDA also recognized this potential as detailed in their recent warning letter to 23andMe.
Hayes applauds the FDA for making a decisive move to ensure patient safety and understanding in the area of DTC genetic testing. We firmly believe that only medical technologies supported by a strong evidence base should be used and that medical tests should only be used under the careful guidance of your healthcare professional. We look forward to further guidance from the FDA regarding all genetic testing, including both DTC genetic tests and clinically available tests marketed as laboratory-developed tests (LDTs).