Fig. 2

Distribution of the significantly differentially methylated positions in transcriptional cluster 2 and 3 placentas, compared to cluster 1, in terms of their linear relationships to gene expression. a Within the 8763 (fetal sex and gestational age corrected) significant sites identified in transcriptional cluster 2, positively correlating positions were more frequently found in a CpG island within a gene body or in the CpG open sea in a gene body or intergenic region (IGR). Significant methylation sites with a negative relationship to gene expression were commonly annotated to a CpG shelf region in a 5′ untranslated region (UTR) or a CpG shore region in a 5′UTR, transcription start site (TSS)1500, or TSS200. b Within the 340 cluster 3 (fetal sex and gestational age corrected) significant sites, only three demonstrated a strong positive relationship with expression: one was in the CpG open sea of AFF3′s 1st exon and the other two were in the CpG open sea of the MGST1 gene body. Negatively correlating positions were more frequently annotated to an open sea region in a TSS200, although several were also in gene bodies or the IGR. Non-significant correlations are shown in light gray, positive correlations are in medium gray, and negative correlations are in dark gray. Nominal p values were obtained from Fisher’s exact tests. P values > 0.05 are not shown