Furthermore, resistance to poly(ADP) ribose polymerase inhibitors and platinum-based chemotherapy in cancer patients harboring a BRCA1 or BRCA2 germline mutation is mediated in a proportion of cases by the acquisition of revertant mutations or intra-genic deletions that restore the open reading frame of BRCA1 or BRCA2[41,42]. This evidence concerns the gene BRCA2 and cancer.