The Norton & Elaine Sarnoff Center for Jewish Genetics cautions regarding the use of direct-to-consumer (DTC) testing such as the 23andMe test to determine one’s personal risk for hereditary cancer. Those who consider using such tests, or who receive such test results, should understand these key points:
The results given by these tests are extremely limited, do not cover all genes that can predispose to genetic conditions, and are potentially misleading. The raw data files of these tests have been shown to provide test results that are falsely positive 40-50% of the time.
Those who receive positive test results without assistance from a genetic counselor or qualified physician are not likely to have adequate preparation to understand their risk or evaluate appropriate preventative measures.
Those who receive negative test results may not understand their remaining risks for hereditary or non-hereditary cancer. Only about 10% of cancers are directly linked to mutations such as those found in the BRCA1/BRCA2 genes.
In almost all cases, physicians and genetic counselors who see patients regarding DTC results will and should recommend that patients get more comprehensive testing.
Read the Sarnoff Center’s full statement on direct-to-consumer cancer testing.