Endothelial nitric oxide synthase (NOS3) rs2070744 polymorphism and risk for multiple sclerosis.

The possible role of oxidative stress and nitric oxide (NO) in the pathogenesis of multiple sclerosis (MS) has been suggested by several neuropathological, biochemical, and experimental data. Because the single-nucleotide polymorphism (SNP) rs2070744 in the endothelial nitric oxide synthase (eNOS or NOS3) gene (chromosome 7q36.1) showed association with the risk for MS in Iranians, we attempted to replicate the possible association between this SNP and the risk for MS in the Caucasian Spanish population. The frequencies of NOS3rs2070744 genotypes and allelic variants in 300 patients diagnosed with MS and 380 healthy controls were assessed with a TaqMan-based qPCR assay. The possible influence of the genotype frequency on age at onset of MS, the severity of MS, clinical evolutive subtypes of MS, and HLA-DRB1*1501 genotype were also analyzed. The frequencies of rs2070744 genotypes and allelic variants were not associated with the risk of developing MS and were not influenced by gender, age at onset and severity of MS, the clinical subtype of MS or the HLA-DRB1*1501 genotype. This study found a lack of association between NOS3 rs2070744 SNP and the risk for MS in Caucasian Spanish people.