The SIR of prostate cancer was 7.8 (95CI: 5.3‒11, P < 0.001), 5.5 (95CI: 2.9‒9.4, P < 0.001), and 11 (95CI: 6.6‒17, P < 0.001) for men, men with an LP/P BRCA1 variant, and men with an LP/P BRCA2 variant, respectively. The gene discussed is BRCA1; the disease is prostate cancer.