Variants in endothelial nitric oxide synthase (eNOS) gene in idiopathic infertile Brazilian men.

PURPOSE: In recent years, considerable concern has been expressed about the deleterious effects of reactive oxygen species (ROS) on sperm function, because ROS at high levels is potentially detrimental to sperm function and quality. Nitric oxide (NO) is a powerful anti-oxidant present in seminal plasma. The aim of the study was to analyze the distribution of the of endothelial nitric oxide synthase (eNOS) gene (T-786C, G894T, e 4a/b) polymorphisms in idiopathic infertile Brazilian men and evaluate the possible role of these polymorphisms in sperm count. METHODS: A case-control study was performed comprising 208 infertile men [n=74 with non-obstructive azoospermia and n=134 with severe oligozoospermia] and 201 fertile men as controls. Genotyping of eNOS polymorphisms was performed by real time (T-786C and G894T) and conventional PCR (4a/b). The results were analyzed statistically and a p-value<0.05 was considered significant. RESULTS: According to the sperm count, relatively similar eNOS polymorphism genotypes and allele frequencies were found among the groups. Combined genotypes of the eNOS polymorphisms did not identify a haplotype associated with idiopathic infertility, even when the patients were separated in non-obstructive azoospermia or severe oligozoospermia. CONCLUSION: In conclusion, the findings demonstrate that, in Brazilian population studied, genetic variations, T-786C, G894T, and e 4a/b, of the eNOS gene are not associated with male infertility.