BRCA2 (breast cancer type 2 susceptibility protein) is a protein found inside cells. In humans, the instructions to make this protein are carried by a gene, also called BRCA2. BRCA2 belongs to the tumor suppressor gene family, and orthologs have been identified in most mammals for which complete genome data are available. The protein encoded by this gene is involved in the repair of chromosomal damage with an important role in the error-free repair of DNA double strand breaks.