The CpG sites in the PluripotentHighVar/SomaticLowVar category clustered into two groups. One group was enriched for Krueppel-associated box and homophilic cell adhesion genes (Figure 1B). This enrichment (i.e. genes with KLF binding sites) is interesting because of the use of KLF4 in reprogramming (Takahashi et al., 2007) and KLF2 in converting hESCs to a mouse ESC-like phenotype (Hanna et al., 2010). The second group was also enriched for genomic imprinting, demonstrating that a second subset of imprinted genes is variable specifically in hPSCs.
