Fig. 5

Cognitive and psychosocial genes affected by folic acid supplementation form two groups based on DNA methylation distribution. A Genes from the GO categories highlighted in italics in Table 2 were characterised using CandiMeth. The genes could be seen to fall into two groups based on absolute levels of DNA methylation across the promoter and GB in normal (placebo) CB. Group I (yellow/green) showed a bimodal pattern of low promoter and high GB methylation levels, often with a promoter CGI; Group II (blue/orange) were not bimodal and usually had no promoter CGI. The index genes investigated earlier are shown at right for comparison. B FA supplementation more often affects GB methylation among these cognitive and psychosocial genes. Mean methylation difference is calculated from the mean percentage methylation of the placebo and the FA group. C CB methylation levels are strongly correlated with the 3rd trimester methylation level of the gene used in this paper. DNA methylation of genes discussed in the paper compared in 2 data sets: CB (this study) and the 3rd trimester brain (GSE58885). The line of the best fit shows strong correlation (R = 0.746175). Note that many of the outlier genes belong to group II