PSA values tend to rise with age, and the total PSA levels (ng ml−1) recommended by the Prostate Cancer Risk Management Programme are as follows (22): 50–59 years, PSA ≥ 3.0; 60–69 years, PSA ≥ 4.0; and 70 and over, PSA > 5.0. The gene discussed is KLK3; the disease is prostate cancer.