EpiSC cells were cultured on murine fibroblast feeders in DMEM/F12 supplemented with 20% KSR, bFGF, nonessential amino acids, b-mercaptoethanol, L-glutamax, penicillin, and streptomycin.ChIP experiment with anti-H3K9me3 antibody was performed as we have described previously. Samples destined for ChIP seq by Illumina HiSeq were prepared according to the manufacturer’s instructions.