Global DNA methylation in genic and intergenic regions of irradiated versus non-irradiated fibroblast cultures.

DNA methylation was assessed with Illumina 450K arrays in primary human fibroblasts at 1–24 h after irradiation with 2 Gy (upper panel) and at 6–72 h after 4 Gy (lower panel). The bars represent the average methylation of all analyzed CpGs that have been annotated to a particular category (promoter, 5' UTR, first exon, gene body, 3' UTR, intergenic). TSS200 is the region from transcription start site (TSS) to -200 bp, TSS1500 from -200 bp to -1,500 bp upstream of TSS. Data are presented as means over means.