BRCA genes

BRCA genes

Tumour suppressor genes, the mutation of which is responsible for an inherited predisposition to breast and ovarian cancer. In 1990 BRCA1 was found to be on the long arm of chromosome 17, and it was cloned in 1994. It is involved in about 5 per cent of all breast cancers. In these cases, and in many cases of invasive breast cancer, there is decreased expression of BRCA1. A considerable number of FRAMESHIFT or NONSENSE MUTATIONS have been found that confer high risk of cancer. BRCA2, located on chromosome 13, is less commonly a cause of inherited breast cancer but is realtively common in Ashkenazi Jewish women.