Patients with heterozygous germline mutations of the BRCA1 or BRCA2 genes (for example, c.5266dupC, c.1961del, c.3700_3704del, c.3756_3759del, c.4035del in BRCA1, c.5946del in BRCA2, etc.)have an increased risk of developing breast cancer (BC), as well as ovarian and other cancers [1]. The gene discussed is BRCA1; the disease is breast cancer.