Figure 2From: Distinguishing epigenetic marks of developmental and imprinting regulationImpact of promoter differential methylation on histone modification profiles at imprinted genes. Histone modification enrichment is compared in mouse embryonic stem cells at imprinted genes with and without a promoter differentially methylated region (DMR). Transcription start sites were assessed for enrichment of H3K4me3, H3K27me3, H3K9me3 and H4K20me3 using source data from Mikkelsen et al. [50]. The presence of one particular modification at an imprinted gene does not preclude the presence of another. A significantly different epigenetic profile for these four marks is observed at genes with a promoter DMR compared to genes without a promoter DMR (chi-square contingency test, P < 0.0001). Germline DMRs are not distinguished from somatic DMRs in this analysis. H3K9me3 and H4K20me3 are exclusively enriched at imprinted genes possessing a promoter DMR. A greater proportion of genes with promoter DMRs are developmentally expressed compared to genes without promoter DMRs (71% compared to 48% respectively); the increase in H3K4me3 and the decrease in H3K27me3 at genes with a promoter DMR likely reflects this (see Additional file 2 and Figure 4).Back to article page