BRCA1 and breast cancer: Monoallelic germline mutations in the BRCA1 and BRCA2 confer high life‐time risks for breast cancer (BC) and ovarian cancer (OC) (Kuchenbaecker et al., 2017) and were found in approximately 24% of index patients who met the inclusion criteria of the German Consortium for Hereditary Breast and Ovarian Cancer (GC‐HBOC) for germline testing (Kast et al., 2016).