These parameters, including age, TT, E2, T/E, INS, FPG, SHBG, DHT, IPSS, Qmax, PSA, TPV, and HOMA-IR, in the BPH group, MetS group, MetS-BPH group, and Normal group, respectively, were compared, except DHT (P = 0.969), differences were statistically significant (all P < 0.05). The gene discussed is KLK3; the disease is metabolic syndrome.