For the risk of ISUP ≥ 2 prostate cancer, this trend was markedly stronger with odds ratios ranging from 0.91 (95%CI: 0.80–1.04) for PSA levels 3 to 4 ng/mL, 1.31 (95%CI: 1.15–1.49) for PSA levels 4 to 6 ng/mL, 2.61 (95%CI: 2.28–2.99) for PSA levels 6 to 10 ng/mL and 4.92 (95%CI: 4.16–5.83) for PSA levels 10 to 15 ng/mL compared to men with PSA from 2 to 3 ng/mL. This evidence concerns the gene KLK3 and Familial prostate cancer.