During Breast Cancer Awareness Month, you may hear a lot about the BRC1 and BRCA2 mutations. A mutation in these genes puts women at a much greater risk of breast cancer. Many women may wonder if they should undergo genetic testing to see if they have this mutation. In fact, the BRCA gene mutation is uncommon, which is why genetic evaluation is not recommended as part of routine testing. Only women who meet a very specific set of criteria are eligible for genetic testing.
The BRCA1 and BRCA2 genes produce tumor-suppressing proteins that repair damaged DNA. Mutations or damage to these genes increase the risk of breast cancer and other types of cancers, such as ovarian cancer. These mutations account for an estimated 20 to 25 percent of hereditary breast cancers in the United States—but only 5 percent of all breast cancer cases.
The BRCA1 or BRCA 2 mutation can be passed down from a person’s mother or father. If a parent carries this mutation, the children have a 50 percent chance of inheriting the mutation.
While about 12 percent of women will develop breast cancer sometime during their lives, 55 to 65 percent of women with the BRCA1 mutation will develop breast cancer. Those with the BRCA2 mutation have a 45 percent risk.
Some of the criteria for genetic testing eligibility include:
· A personal history of breast cancer at a young age
· A history of ovarian cancer and a close relative with ovarian cancer
· A male relative with breast cancer
· Two or more relatives with ovarian cancer
· A relative with a known BRCA1 or BRCA2 mutation
· A family member with both breast and ovarian cancers.
If other family members have been diagnosed with breast cancer, it is important to for the patient to be diligent and participate in regular breast cancer screenings. However, a family history of breast cancer does not automatically mean that these breast cancer incidents were due to a genetic mutation. Patients who are concerned about their family medical history and the way it can affect their health should speak with their physicians.
The Mayo Clinic
Centers for Disease Control