We also found a negative causal effect of genetic predisposition towards agents acting on the renin-angiotensin system (OR = 0.94; 95% CI = 0.91–0.97, P = 0.0007) in prostate cancer, whereas vasodilators used in cardiac diseases were detrimental (OR = 1.25; 95% CI = 1.13–1.38, P = 2.48E–05). This evidence concerns the gene REN and Familial prostate cancer.