DNA methylation in methylenetetrahydrofolate reductase (MTHFR) gene promoter and 5-formyl-tetrahydrofolate (5-formyl-THF) levels in folic acid supplemented pregnant women

Abstract

Introduction: DNA methylation is an epigenetic modification critical for gene expression regulation. Folate metabolism cycle is intricately regulated to provide methyl groups for DNA methylation. The genetic and epigenetic influences on folate metabolism and on the levels of different folate forms are yet unclear. Methylenetetrahydrofolate reductase (MTHFR) is a key enzyme in folate metabolism that determines the availability of methyl groups. The study aims were to assess the methylation status of MTHFR gene promoter and to investigate the association between DNA methylation status of MTHFR promoter and concentrations of 5-formyl-tetrahydrofolate in folic acid supplemented Sri Lankan pregnant women. Methods: Methylation Specific PCR was used to analyse methylation status of MTHFR promoter (n=20) at two time points: baseline (before FA supplementation) and delivery (after FA supplementation). Available data on 5-formyl-THF levels of these pregnant women were compared with the methylation status. Wilcoxon rank test was performed to compare the change in DNA methylation status at baseline and delivery, while one-way ANOVA was performed to compare the mean change of 5-formyl-THF level from baseline to delivery between groups