Our findings revealed that there was no significant difference in the genotype frequency of NOS3 gene in ADPKD patients (p=0.311).The age of onset of ESRD in ADPKD patients, harbouring the T allele of this polymorphism, was two years lower than G/G patients, but this difference was not significant (p =0.641). The gene discussed is NOS3; the disease is autosomal dominant polycystic kidney disease.