It has been demonstrated that the pathogenic variants (PV) of BRCA1/BRCA2 genes, whether germline or somatic, represent a predictive biomarker of greater sensitivity to treatment with inhibitors of the enzyme poly (ADP-ribose) polymerase (PARP), which intervenes in DNA repair damaged single-strand prostate cancer in patients with hormone-resistant metastatic prostate cancer. This evidence concerns the gene BRCA1 and prostate cancer.