Association between MTHFR C677T Variant and Risk for Conotruncal Heart Defects in Egyptian Children: A Meta-analysis based on 217 cases and 213 controls

Abstract Stratification analysis studies showed that ethnicity has a significant association regarding MTHFR C677T variant and congenital heart diseases (CHDs) risk, and many published studies have controversial conclusions toward this association. A total of 3 case-control studies in the Egyptian population published before 2021 were included in this meta-analysis, besides new 186 participants to evaluate the association between the MTHFR C677T variant and the risk for CHDs. The association was assessed by the odds ratio (OR) with a 95% confidence interval (CI) based on 217 cases and 213 controls. The overall meta-analysis showed a significant association between MTHFR C677T variant and CHDs risk in Egyptian children with heterogeneity (Heterogeneity = 0.001) in all the genetic models with the highly significant association in T vs. C allele (pooled OR 1.85, 95% CI: 1.41–2.43; p-value < 0.0001). The limitation of the analysis was detected by Hardy-Weinberg equilibrium (HWE) in two studies that demonstrated statistical significance. Our results support the MTHFR − 677T allele as a susceptibility factor for CHDs in the Egyptian pediatric population.