Test only reports 3 out of more than 1,000 known BRCA mutations and negative result doesn’t rule out increased cancer risk
Silver Spring, Maryland—(ENEWSPF)—March 6, 2018
By: Rosemary Piser
The Food and Drug Administration (FDA) has authorized the Personal Genome Service Genetic Health Risk (GHR) Report for BRCA1/BRCA2 (Selected Variants). This is the first direct-to-consumer (DTC) test to report on three specific BRCA1/BRCA2 breast cancer gene mutations that are most common in people of Ashkenazi (Eastern European) Jewish descent. However, these three mutations are not the most common BRCA1/BRCA2 mutations in the general population.
The new test analyzes DNA collected from a self-collected saliva sample. A report describes if:
- a woman is at increased risk of developing breast and ovarian cancer, and
- a man is at increased risk of developing breast cancer or may be at increased risk of developing prostate cancer.
The test only detects three out of more than 1,000 known BRCA mutations. As a result, a negative test finding does not rule out the possibility that an individual carries other BRCA mutations that increase cancer risk.
At today’s announcement, Donald St. Pierre, acting director of the Office of In Vitro Diagnostics and Radiological Health in the FDA’s Center for Devices and Radiological Health said, “This test provides information to certain individuals who may be at increased breast, ovarian or prostate cancer risk and who might not otherwise get genetic screening, and is a step forward in the availability of DTC genetic tests. But it has a lot of caveats. While the detection of a BRCA mutation on this test does indicate an increased risk, only a small percentage of Americans carry one of these three mutations and most BRCA mutations that increase an individual’s risk are not detected by this test. The test should not be used as a substitute for seeing your doctor for cancer screenings or counseling on genetic and lifestyle factors that can increase or decrease cancer risk.”
According to according to a National Cancer Institute study, the three BRCA1/BRCA2 hereditary mutations detected by the test are present in about 2 percent of Ashkenazi Jewish women. They rarely occur (0 percent to 0.1 percent) in other ethnic populations. All individuals, whether they are of Ashkenazi Jewish descent or not, may have other mutations in BRCA1 or BRCA2 genes, or other cancer-related gene mutations that are not detected by this test. For this reason, a negative test result could still mean that a person has an increased risk of cancer due to gene mutations.
In addition, most cases of cancer are not caused by hereditary gene mutations but are thought to be caused by a wide variety of factors, including smoking, obesity, hormone use and other lifestyle issues. For all of these reasons, it is important for patients to consult their health care professional who can help them understand how these factors impact their individual cancer risk and what they can do to modify that risk.
The FDA’s review of the test determined that the company provided sufficient data to show that the test is accurate (i.e., can correctly identify the three genetic variants in saliva samples), and can provide reproducible results. The company submitted data on user comprehension studies, using representative GHR test reports, that showed instructions and reports were generally easy to follow and understood by a consumer. The test report provides information describing what the results might mean, how to interpret results and where additional information about the results may be found.
The FDA granted the marketing authorization to 23andMe.
“Being the first and only direct-to-consumer genetics company to receive FDA authorization to test for cancer risk without a prescription is a major milestone for 23andMe and for the consumer,” said Anne Wojcicki, 23andMe CEO and co-founder. “We believe it’s important for consumers to have direct and affordable access to this potentially life-saving information. We will continue pioneering a path for greater access to health information, and promoting a more consumer-driven, preventative approach to health care.”
For additional information, contact Deborah Kotz or call 1-888-INFO-FDA.