BRCA1 and BRCA2 genes- HBOC

Hereditary Breast and Ovarian Cancer (HBOC) syndrome

Of the 5-10% of breast and ovarian cancer that is caused by an inherited mutation in a single gene, most cases are due to a mutation in the BRCA1 or BRCA2 genes. A mutation in one of these genes impairs DNA repair and thus increases an individual's probability of developing certain cancers. The cancers most commonly seen in individuals with a BRCA1 or BRCA2 mutation are female breast cancer (50-85% lifetime risk) and ovarian cancer (20-40% lifetime risk). Other cancers are also seen more frequently in people with a BRCA mutation, including male breast cancer (6-9% lifetime risk), prostate cancer, melanoma (with a BRCA2 mutation), and pancreatic cancer. Although a mutation in BRCA1 or BRCA2 increases the chances of developing cancer, there are individuals who inherit a mutation in one of these genes and never develop cancer. Cancer predisposition caused by a mutation in BRCA1 or BRCA2 is inherited in an autosomal dominant manner, meaning each first degree relative (parent, child, and sibling) of an individual with this condition has a 50% chance of inheriting the disease causing mutation.

To learn more about HBOC visit our HBOC Kintalk group at 

For resources please go to Kintalk's HBOC resource list or click on this link