Genetic Testing
Mutations to either breast cancer gene — BRCA1 or BRCA2 — significantly
increase your risk of breast cancer and ovarian cancer when compared with
the cancer risk of a woman without a BRCA gene mutation. Men with inherited
BRCA gene mutations also face an increased risk of breast cancer. BRCA
mutations may increase the risk of other types of cancer in women and
men as well.
You might be at increased risk of having a BRCA gene mutation — and
a candidate for BRCA gene testing — if you have:
- A personal history of breast cancer diagnosed at a young age (premenopausal),
breast cancer affecting both breasts (bilateral breast cancer), or both
breast and ovarian cancers
- A personal history of ovarian cancer and a close relative with ovarian
cancer, premenopausal breast cancer, or both
- A history of breast cancer at a young age in two or more close relatives,
such as your parents, siblings, or children
- A male relative with breast cancer
- A family member who has both breast and ovarian cancers
- A family member with bilateral breast cancer
- Two or more relatives with ovarian cancer
- A relative with a known BRCA1 or BRCA2 mutation
- Ashkenazi (Eastern European) Jewish ancestry, with a close relative who
has breast or ovarian cancer
- Ashkenazi Jewish ancestry and a personal history of ovarian cancer
Who should consider BRCA gene testing?
Ideally, in a family that might carry a BRCA mutation, the youngest family
member who has breast cancer will have the BRCA gene test first. Genetic
counselors can help you identify who this person is, based on family history.
If this individual agrees to genetic testing and doesn't carry the
BRCA gene mutation, then other family members won't benefit from taking the test.
The BRCA gene test is a blood test that uses DNA analysis to identify harmful
changes (mutations) in either one of the two breast cancer susceptibility
genes — BRCA1 and BRCA2. Women who have inherited mutations in these
genes face a much higher risk of developing breast cancer and ovarian
cancer compared with the general population. The BRCA gene test is offered
only to people who are likely to have an inherited mutation, based on
personal or family history, or who have specific types of breast cancer.
The BRCA gene test isn't routinely performed on women at average risk
of breast and ovarian cancers.
Having a BRCA gene mutation is uncommon. Inherited BRCA gene mutations
are responsible for about 5 percent of breast cancers and about 10 to
15 percent of ovarian cancers.
After having a BRCA gene test performed, you will learn if you carry an
inherited BRCA gene mutation and receive an estimate of your personal
risk of breast cancer and ovarian cancer. Genetic counseling is an important
part of the BRCA gene test process.