While Loeb et al. reported that PSA velocity in both healthy men and patients with prostate cancer aged ≥ 50 years was not affected by age, Moul et al. suggested that PSA velocity in both healthy men and patients with prostate cancer aged 50–59 years was lower than that in patients aged 70 years or older15,16. Here, KLK3 is linked to Familial prostate cancer.