BRCA-1 and BRCA-2

BRCA-1 and BRCA-2 are two genes that are linked with hereditary breast and ovarian cancers. About 200,000 women are diagnosed with invasive breast cancer each year and about 23,000 with ovarian cancer (according to the American Cancer Society). Of these cancers, about 5% to 10% will be due to a mutation in one of the BRCA genes. Men can also inherit an increased risk of developing breast cancer, primarily from an alteration in the BRCA-2 gene.

Individuals with mutations in BRCA1 or BRCA2 have significantly elevated risks for breast cancer (up to 80% lifetime risk), ovarian cancer (up to 40% lifetime risk), bilateral breast cancer and other types of cancers. BRCA mutations are inherited and passed from generation to generation. One half of the time, they are passed from the father’s side of the family.

The DNA in white blood cells is used to detect mutations in the BRCA genes. While the gene products (proteins) of the BRCA genes act only in breast and ovarian tissue, the genes are present in every cell of the body and blood is the most easily accessible source of that DNA.

The test for BRCA mutations is done on a blood sample collected by needle from a vein in the arm. The test does not require surgical biopsy of breast or ovarian tissue.