Genetic tests can determine if someone has inherited an abnormal BRCA1 or BRCA2 gene. Inherited mutations in other genes are also associated with breast cancer. These abnormal gene changes are much less common and don't seem to increase risk as much as abnormal BRCA1 and BRCA2 genes, which are considered rare. Still, because these genetic mutations are more rare, they haven't been studied as much as the BRCA genes.
A genetic counselor may order testing for mutations in the following genes:
- mismatch repair genes (MLH1, MSH2, MSH6, PMS2, EPCAM)
These can be tested for individually or as part of a larger gene panel that includes BRCA1 and BRCA2. Decisions about what tests to perform are based on your personal or family history of breast cancer and other cancers.
If you test positive for any of the above abnormal genes, your genetic counselor can advise you about possible next steps, including increased screening, risk-reducing hormonal therapy, or, in some cases, risk-reducing surgery.
Learn more about the risk of breast cancer linked to each of these inherited genetic mutations.
This content was developed with contributions from the following experts:
Christina Nixon, MS, LCGC, a licensed certified genetic counselor with the Cancer Risk Assessment and Genetics Program at Main Line Health
Peggy Cottrell, MS, LCGC, a licensed certified genetic counselor at Holy Name Medical Center, and the Genetics Program Coordinator at Sharsheret