DNMT3B and immunodeficiency-centromeric instability-facial anomalies syndrome 1: Homology-directed repair (HDR) by CRISPR/Cas9 editing was implemented to rescue the catalytic activity of DNMT3B in two iPSCs derived from ICF1 patients pR and pG (Sagie et al., 2014) (all further reference to ICF patients or cells relates to ICF1 only) (Figure 1—figure supplement 1).