There was little evidence that genetically proxied ACE inhibition was associated with risk of breast cancer (OR 0.98, 95% CI 0.94 to 1.02; P = 0.35) or lung cancer (OR 1.01, 95% CI 0.92 to 1.10; P = 0.93) and weak evidence for an association with prostate cancer risk (OR 1.06, 95% CI 0.99 to 1.13; P = 0.08). This evidence concerns the gene ACE and prostate cancer.