MR estimates were supportive of an association between lower levels of PCSK9 gene expression (instrumented using the eQTL) and a lower risk of overall prostate cancer (OR = 0.90, 95% CI = 0.86 to 0.95, P = 5.50 × 10−5, per SD reduction in PCSK9 transcript levels). This evidence concerns the gene PCSK9 and Familial prostate cancer.