Fig. 4

Functional genomic analysis of 5hmC changes in MSCs of two different human age groups. a Left: Violin plot showing the distribution of CpG density for hyper5hmCs and hypo5hmC sites against the background sites in the Infinium HumanMethylation450 microarray (Wilcoxon non-parametric test; p = 0.23, D = 0.02 and p < 0.001, D = −0.25, respectively). Center: Stacked bar chart showing the relative proportions of CpG sites, classified according to their CpG Island status, for the hyper- and hypo5hmC sites, and background probe sets. Hyper5hmCs sites are preferentially located in CpG Island regions (Chi square test; p < 0.001, OR 1.54), whereas hypo5hmC sites are preferentially located in non-CpG Island regions (Chi square test; p < 0.001, OR 2.09). Right: Stacked bar chart describing the classification of hyper5hmC and hypo5hmC sites and background sites according to their relative genomic location. Both are enriched in intergenic regions (Chi square test; p < 0.001, OR 1.51 and p < 0.001, OR 1.80, respectively). b Violin plots showing the distribution of distances to centromeres (left) (Wilcoxon non-parametric test; p = 0.006 D = 0.06, and p = 0.23 D = 0.02, respectively) and telomeres (right) for the hyper5hmC and hypo5hmC sites and background probe sets (Wilcoxon non-parametric test; p < 0.001 D = −0.16, and p = 0.01 D = −0.01, respectively)