To determine whether DNA methylation of specific target sites on the GR promoter change in response to maternal care, we mapped the differences in methylation of individual cytosines, focusing on a region around the NGFIA consensus sequence within the exon 17 promoter. The results reveal significant differences in the methylation of specific regions of the exon 17 GR promoter sequence. Notably, the cytosine within the 5' CpG dinucleotide of the NGFIA consensus sequence (Figure 2) is always methylated in the offspring low-LG mothers, and rarely methylated in the offspring of high-LG dams. This is consistent with site-specific DNA methylation silencing of the GR promoter.
