Men with PSA > 2.5 ng/ml had lower volume and sperm concentration but no difference in motility and men diagnosed with prostate cancer had only lower median total sperm count (205 million) and median concentration (81 million/ml) compared to controls with PSA <2.5 ng/ml (314 million and 105.5 million/ml, respectively). This evidence concerns the gene KLK3 and prostate cancer.