Fig. 5

DNA methylation of CpG locus at OXTR gene promoter in human umbilical vein. a Sequence analysis identified one CpG island in exon 1 that contains 22 CpG sites, located at positions + 55 to + 225 from the TSS in the OXTR gene promoter. b mRNA levels of OXTR in HUVECs after treatment with 5-Aza. c–d Represent the mean methylation status of the genomic regions in OXTR gene promoter. Each bar represents mean methylation percentage in a genomic region of a sample. e Expression analysis of OXTR gene and its correlation with methylation levels of 22 CpG sites. DNA methylation/mRNA correlation plots for OXTR gene identified by causal inference test. The y-axis represents the relative expression level of OXTR gene which was detected with qRT-PCR method. The x-axis represents the relative mean methylation level of all the 22 CpG sites in OXTR gene. r: Pearson correlation coefficient. f mRNA levels of OXTR gene in normal and pre-eclamptic HUVECs after 5-Aza treatment (N = 8 each group). Error bars denote SEM.*P < 0.05; ***P < 0.001. N number of participants