Although the function of this variant in prostate carcinogenesis remains to be determined, rs1799983 located in exon 7 of NOS3 gene, causing an amino acid substitution within the N-terminal oxygenase domain of NOS3 enzyme (34), may contribute to variability in oxidative stress and risk of prostate cancer by interacting with other genetic or hormonal factors in this subgroup population. The gene discussed is NOS3; the disease is Familial prostate cancer.