Evaluation of <i>NOS3</i> 894G&gt;T (p.Glu298Asp) Variant as Risk Factor for Open Neural Tube Defects in Infants from Western Mexico

<b><i>Background:</i></b> The nitric oxide (NO) synthase 3 (<i>NOS3</i>) 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. <b><i>Aim:</i></b> This study aimed to evaluate the <i>NOS3</i> (p.Glu298Asp) variant as a potential genetic risk factor in infants with isolated open and closed NTDs (CNTDs) from Western Mexico. <b><i>Materials and Methods:</i></b> The studied population included 114 live-born infants with open and CNTDs (cases) and 155 neonates without major birth defects (controls). Genotyping of the <i>NOS3</i> 894G>T (p.Glu298Asp) variant was performed by PCR amplification and direct Sanger sequencing. Data were analyzed using logistic regression analysis. <b><i>Results:</i></b> The <i>NOS3</i> 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 <i>NOS3</i> 894G>T gene variants and CNTDs. <b><i>Conclusions:</i></b> This study indicates that the <i>NOS3</i> 894G>T (p.Glu298Asp) variant is associated with an increased risk of ONTDs in the studied Mexican patients.