The present study was carried out to categorize the patients into prostatic carcinoma, benign prostatic hyperplasia, or prostatitis based on serum prostate specific antigen, prostatic acid phosphatase, calcium and phosphorus levels, and DRE and to evaluate the discriminating power of these in distinguishing controls and cases to reduce the risk of unnecessary biopsy. The gene discussed is KLK3; the disease is prostate carcinoma.