The U.S. Food and Drug Administration has allowed marketing of 23andMe Personal Genome Service Genetic Health Risk (GHR) tests for 10 diseases or conditions. These are the first direct-to-consumer (DTC) tests authorized by the FDA that provide information on an individual's genetic predisposition to certain medical diseases or conditions, which may help to make decisions about lifestyle choices or to inform discussions with a health care professional.
"Consumers can now have direct access to certain genetic risk information," said Jeffrey Shuren, M.D., director of the FDA's Center for Devices and Radiological Health. "But it is important that people understand that genetic risk is just one piece of the bigger puzzle, it does not mean they will or won't ultimately develop a disease."
The GHR tests are intended to provide genetic risk information to consumers, but the tests cannot determine a person's overall risk of developing a disease or condition. In addition to the presence of certain genetic variants, there are many factors that contribute to the development of a health condition, including environmental and lifestyle factors.
The 23andMe GHR tests work by isolating DNA from a saliva sample, which is then tested for more than 500,000 genetic variants. The presence or absence of some of these variants is associated with an increased risk for developing any one of the following 10 diseases or conditions:
- Parkinson's disease, a nervous system disorder impacting movement;
- Late-onset Alzheimer's disease, a progressive brain disorder that destroys memory and thinking skills;
- Celiac disease, a disorder resulting in the inability to digest gluten;
- Alpha-1 antitrypsin deficiency, a disorder that raises the risk of lung and liver disease;
- Early-onset primary dystonia, a movement disorder involving involuntary muscle contractions and other uncontrolled movements;
- Factor XI deficiency, a blood clotting disorder;
- Gaucher disease type 1, an organ and tissue disorder;
- Glucose-6-Phosphate Dehydrogenase deficiency, also known as G6PD, a red blood cell condition;
- Hereditary hemochromatosis, an iron overload disorder; and
- Hereditary thrombophilia, a blood clot disorder.
The FDA reviewed data for the 23andMe GHR tests through the de novo premarket review pathway, a regulatory pathway for novel, low-to-moderate-risk devices that are not substantially equivalent to an already legally marketed device. Along with this authorization, the FDA is establishing criteria, called special controls, which clarify the agency's expectations in assuring the tests' accuracy, reliability and clinical relevance. These special controls, when met along with general controls, provide reasonable assurance of safety and effectiveness for these and similar GHR tests.
In addition, the FDA intends to exempt additional 23andMe GHR tests from the FDA's premarket review, and GHR tests from other makers may be exempt after submitting their first premarket notification. A proposed exemption of this kind would allow other, similar tests to enter the market as quickly as possible and in the least burdensome way, after a one-time FDA review.
"The special controls describe the testing that 23andMe conducted to demonstrate the performance of these tests and clarify agency expectations for developers of other GHRs," said Dr. Shuren. "By establishing special controls and eventually, a premarket review exemption, the FDA can provide a streamlined, flexible approach for tests using similar technologies to enter the market while the agency continues to help ensure that they provide accurate and reproducible results."
Excluded from today's marketing authorization and any future, related exemption are GHR tests that function as diagnostic tests. Diagnostic tests are often used as the sole basis for major treatment decisions, such as a genetic test for BRCA, for which a positive result may lead to prophylactic (preventative) surgical removal of breasts or ovaries.
Authorization of the 23andMe GHR tests was supported by data from peer-reviewed, scientific literature that demonstrated a link between specific genetic variants and each of the 10 health conditions. The published data originated from studies that compared genetic variants present in people with a specific condition to those without that condition. The FDA also reviewed studies, which demonstrated that 23andMe GHR tests correctly and consistently identified variants associated with the 10 indicated conditions or diseases from a saliva sample.
The FDA requires the results of all DTC tests used for medical purposes be communicated in a way that consumers can understand and use. A user study showed that the 23andMe GHR tests' instructions and reports were easy to follow and understand. The study indicated that people using the tests understood more than 90 percent of the information presented in the reports.
Risks associated with use of the 23andMe GHR tests include false positive findings, which can occur when a person receives a result indicating incorrectly that he or she has a certain genetic variant, and false negative findings that can occur when a user receives a result indicating incorrectly that he or she does not have a certain genetic variant. Results obtained from the tests should not be used for diagnosis or to inform treatment decisions. Users should consult a health care professional with questions or concerns about results.
The FDA granted market authorization of the Personal Genome Service GHR tests to 23andMe, Inc.