Compared to normal brain, partially hypermethylated regions in the matched IDH mutant gliomas samples were enriched by lower signals of the two active histone modifications, H3K4me3 and H3K27ac, while no significant difference could be observed in flanking under-methylated regions (Fig. 2G, Additional file 1: Fig. S3A). The gene discussed is IDH2; the disease is central nervous system cancer.