Although prostate cancer is generally considered to be an immunologically cold cancer with only between 50–100 nonsynonymous DNA alterations per cancer exome (i.e., 1–2 mutations per Mb), germline or somatic mutations in DNA repair genes especially homologous recombination (HR) repair genes (BRCA2, ATM, etc.)have been uncovered in a significant percentage of metastatic castration-resistance prostate cancer (mCRPC) patients. The gene discussed is BRCA2; the disease is cancer.