Fig. 5

Differences in DNA methylation and gene expression before versus after differentiation of human primary myoblasts of obese and non-obese subjects. a Overlap of significant CpG sites with decreased and increased DNA methylation, respectively, after differentiation of human primary myoblasts of non-obese (n = 14) and obese (n = 14) subjects. b Significantly enriched gene ontology (GO)-terms (q < 0.05) of genes that exhibit differential DNA methylation only in obese. c Distribution of significant CpG sites that showed differential DNA methylation during myogenesis in non-obese and obese subjects compared with all analyzed CpG sites on the array and also between non-obese and obese in relation to gene regions, CpG island regions, and enhancer-regions. * P _χ2 < 0.05 compared with all analyzed, # P _χ2 < 0.05 between non-obese and obese subjects. d Overlap of downregulated and upregulated genes during myogenesis between non-obese (n = 13) and obese subjects (n = 13). Networks of certain genes only differentially expressed during myogenesis in obese (e) and non-obese (f) subjects, respectively, and related GO-terms to these genes. Green, downregulated; red, upregulated. Node size is based on expression fold change. g Genes (different probes) regulated in opposite directions during myogenesis in non-obese and obese subjects (* q < 0.05). h The top graph shows mRNA expression of genes only differentially expressed and methylated in obese subjects during myogenesis that are associated with DNA methylation, obesity, and/or metabolic disorders as well as myogenesis and/or myopathies. Values are presented as log2 to reduce magnitude and better visualize expression of all genes grouped in each category in one graph. The lower graph shows DNA methylation of significant CpG sites annotated to genes with a red box in the top graph (* q < 0.05). i Significant enrichment of the number of CpG sites within obesity candidate genes with differential DNA methylation at P < 0.05 between non-obese and obese subjects in myoblasts and myotubes, respectively (* P _χ2 < 0.05). Data are presented as mean ± SEM