P-131: The Study of Nitric Oxide Synthase 3 (NOS3) 4a4b Gene Polymorphism in Iranian Infertile Men with Varicocele
Varicocele is an abnormal dilation and tortuosity of veins of pampiniform plexus that drains the testis and causes an important change in semen.This abnormality is often one of the most common risk factors for male infertility. The aim of this study was to investigate the relationship between nitric oxide synthase 3 (NOS3) 4a4b (rs61722009) gene polymorphism, as a common genetic factor, with the risk of varicocele in Iranian infertile men. Three types of eNOS gene polymorphisms have been described. G894T, T-786C and 4a4b, a variable number of tandem repeats (VNTR), within intron 4 of the eNOS gene, accounts for >25% of basal plasma NO generation, suggesting that this gene might have an important role in NO-mediated physiology.
Materials and methods
Sixty infertile men with varicocele (mean age 31.58 ± 6.16 years) and forty-five healthy control (mean age 31.26 ± 5.3 years) with documented fertility were recruited in this study. Both group were analyzed for the VNTR polymorphism in intron 4 of the nitric oxide synthase 3 by the conventional polymerase chain reaction (PCR).
As a result, in patient group genotype frequency of AB is 20% and AA is 80%. Signiﬁcant differences were not found between infertile cases and healthy controls with regard to 4a/b polymorphism. Therefore, no genetic relationship was observed between NOS3 gene 4a4b polymorphism and varicocele.
The ﬁndings demonstrate that, in Iranian population studied, genetic variation (4a/b) of the NOS3 gene, are not associated with Iranian infertile men with varicocele. Furthermore, studies with larger samples need to be done to confirm these finding.