Evaluation of

Background: The nitric oxide (NO) synthase 3 (NOS3) 894G>T (p.Glu298Asp) variant has been associated with an elevated risk of neural tube defects (NTDs) in Caucasians. This association suggests a link between the NO and folic acid pathways. Aim: This study aimed to evaluate the NOS3 (p.Glu298Asp) variant as a potential genetic risk factor in infants with isolated open and closed NTDs (CNTDs) from Western Mexico. Materials and Methods: The studied population included 114 live-born infants with open and CNTDs (cases) and 155 neonates without major birth defects (controls). Genotyping of the NOS3 894G>T (p.Glu298Asp) variant was performed by PCR amplification and direct Sanger sequencing. Data were analyzed using logistic regression analysis. Results: The NOS3 894T allele (adjusted odds ratio [aOR] = 2.1; 95% confidence interval [95% CI]: 1.3-3.4), the 894GT (aOR = 2.3; 95% CI: 1.3-4.1), and the 894GT/TT (aOR = 2.6; 95% CI: 1.4-4.7) genotypes were significantly associated with open NTDs (ONTDs). There was no association between the NOS3 894G>T gene variants and CNTDs. Conclusions: This study indicates that the NOS3 894G>T (p.Glu298Asp) variant is associated with an increased risk of ONTDs in the studied Mexican patients.