The association between polymorphism of methylenetetrahydrofolate reductase C677T and bronchial asthma in children: a meta-analysis

Abstract

Abstract Background: The methylenetetrahydrofolate reductase (MTHFR) gene encodes the folate cycle enzyme involved in folate metabolism. Several studies have revealed the effects of the MTHFR C677T polymorphism in child asthma, but the results were inconsistent. Objective: We intends to systematically evaluate the association between MTHFR C677T polymorphism and child asthma in the existing studies. Methods: We performed a comprehensive and systematic search of PubMed, Web of Science and CNKI database, and six studies were finally included in this meta-analysis to determine whether MTHFR C677T variant contributed to the risk of asthma in children. Results: Pooled data indicated that the MTHFR C677T polymorphism significantly increased asthma risk in children by the random-effects model (odds ratio (OR) = 2.06, 95% confidence interval (CI) = 1.33–3.19). In the subgroup analysis stratified by ethnicity, increased risk was found in Asians (OR = 2.24, 95% CI = 1.39–3.62). Conclusion: Our meta-analysis demonstrated a definite correlation between MTHFR C677T polymorphism and asthma risk in children.