Genetic predisposition to BC is associated with germline mutations to key tumour regulatory genes, including the homologous recombination repair BReast CAncer (BRCA) genes BRCA1 and BRCA2. A deleterious/pathogenic mutation in BRCA1 and/or BRCA2 (BRCAm) significantly increases the likelihood of developing BC over a person’s lifetime [2], and germline BRCAm (gBRCAm) predominate over somatic BRCAm in populations without strong germline founder mutations [3]. Here, BRCA1 is linked to breast cancer.