In a large survey study performed in men to investigate the effect of prostate cancer screening in CRC screening uptake [45], adherence to prostate cancer screening exerted the largest independent effect on CRC adherence regardless of the method used for screening (prostate-specific antigen or digital rectal exam) (OR 3.51, CI 95% (3.30–3.73)). The gene discussed is KLK3; the disease is colorectal carcinoma.