<prompt> BRCA 1 positive woman have___ increased risk of breast carcinoma10204060  <response>: D 60 BRCA1 gene has been cloned is located on the long arm of chromosome 17 17q. The gene frequency in the population is approximately 0.0006. It does, however, occur with greater frequency in certain populations such as Ashkenazi Jews, in whom there is often a common founder mutation. BRCA2 is located on chromosome 13q there is an association with male breast cancer. Women who are thought to be gene carriers may be offered breast screening and ovarian screening in the case of BRCA1, which is known to impart a 50 lifetime risk of ovarian cancer, usually as part of a research programme, or genetic counselling mutation analysis. Those who prove to be gene positive have a 50-80 risk of developing breast cancer, predominantly while pre-menopausal. Many will opt for prophylactic mastectomy. Although this does not completely eliminate the risk, it does reduce it considerably 