The genetic variation observed in BRCA 1/2 + families.

e12511 Background: While BRCA1 and BRCA2 are high penetrance genes accounting for a significant proportion of hereditary breast and ovarian cancers (HBOC), many other genes have been associated with increased risks of both cancers. Multigene panel tests have recently emerged to analyze multiple genes simultaneously. Although multigene panels were initially proposed for use in families with hereditary cancer patterns testing negative for BRCA 1/2, commercialization combined with updates in professional guidelines have led to increased utilization of multigene panels as a 1st-tier test for HBOC. However, the possible utility of multigene tests in families with known BRCA1/2 mutations has not previously been investigated. Methods: All BRCA 1/2 positive pedigrees obtained in a suburban hospital genetics program over a 15 year period were reviewed retrospectively. Pedigrees with a complex presentation of cancers, such as competing diagnoses, syndrome specific cancers present in two or more branches of a family...