Although the majority of BC and OC cases are sporadic, approximately 10% of ovarian cancer cases and 3–5% of BC cases are due to germline mutations in the genes BRCA1 and BRCA2 [4–6], which has been described as hereditary breast-ovarian cancer (HBOC) syndrome [5,7]. This evidence concerns the gene BRCA1 and hereditary breast ovarian cancer syndrome.