BRCA Genes and At-Home Testing: A Cautionary Tale
By Emily Bonham
Jun 11, 2018
Updated Nov 17, 2023
5 min read
At-home genetic testing can spark a meaningful conversation about how family history and genetics play a role in health risks. Identifying a mutation in a cancer-related gene can guide discussion of appropriate risk reduction options, which can be life-saving. However, genetic counselors and other healthcare professionals caution about the limitations of at-home tests.
In April 2018, the U.S. Food and Drug Administration (FDA) approved an at-home genetic test that provides information about risk for inherited cancer. The test, which is marketed directly to consumers by 23andMe, looks for three specific harmful alterations (mutations) in the BRCA1 and BRCA2 genes using DNA collected from a saliva sample. Having a mutation in BRCA1 or BRCA2 can increase a woman’s risk to develop breast and ovarian cancer and a man’s risk to develop breast and prostate cancer.
Of the over 1,000 different mutations that have been identified in the BRCA1 and BRCA2 genes, the 23andMe test looks for only the three which tend to occur more frequently in people of Ashkenazi Jewish ancestry. Thus, even if no mutation is found by the at-home test, this does not rule out the possibility of a mutation in BRCA1 or BRCA2. In addition, dozens of other genes can impact a person’s risk to develop cancer; these genes are not included on 23andMe test.
Genetic counselors caution, the 23andMe test does not provide a full accurate cancer risk assessment. The FDA press release states, “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 emphasizes that confirmatory testing through a healthcare professional is needed before making medical decisions based on test results. The use of the test carries significant risks if individuals use the test results without consulting a physician or genetic counselor. A healthcare provider can also explain how lifestyle and environmental factors play a role in cancer risk and what individuals can do to take control of these factors.
Even those who have a negative test result but have a strong family history of cancer should meet with a genetic counselor to discuss clinical testing options. Intermountain Healthcare’s Oncology Genetic Counseling team can collect and interpret family history, discuss and coordinate testing for a variety of cancer-related genes, provide individualized recommendations based on test results, and help anticipate the emotional and social impacts this testing can have.
Anyone with questions about their family history of cancer, inherited cancer risks, or at-home genetic testing can meet with an Intermountain Healthcare Genetic Counselor by calling:
Intermountain’s Cancer Genetic Counselors can also discuss testing options such as HerediGene™ - Hereditary Breast Cancer Panel. This clinically based genetic test, offered by Intermountain Precision Genomics, provides comprehensive analysis of 18 genes associated with inherited breast cancer (ATM, BARD1, BRCA1, BRCA2, BRIP1, CDH1, CHEK2, MRE11, MUTYH, NBN, NF1, PALB2, PTEN, RAD50, RAD51C, RAD51D, STK11, TP53).