Polymorphisms of the endothelial nitric oxide synthase gene in premenopausal women with polycystic ovary syndrome

Abstract Objectives To investigate the association of two common genetic polymorphisms of the gene encoding for endothelial nitric oxide synthase ( Nos3 ), the enzyme catalyzing the production of nitric oxide (NO), with occurrence of the polycystic ovary syndrome (PCOS). Methods In a prospective case–control study, we analyzed 2 polymorphisms of the Nos3 gene cluster ( Nos 3 exon 7 Glu298Asp and 27-base pair repeat in intron 4 of Nos3 ) in a series of 210 premenopausal Caucasian women with PCOS and 171 healthy controls using pyrosequencing and PCR, respectively. Women completed a detailed questionnaire and underwent a peripheral venous puncture, ultrasonography, and a standardized oral glucose tolerance test (OGTT). Results Genotype frequencies were not significantly different among women with PCOS and controls for the exon 7 Nos3 and the intron 4 Nos3 polymorphism ( p  = 0.3 and 0.2, respectively). Conclusions In our series, two common polymorphisms of the Nos3 gene cluster were not associated with occurrence of PCOS.