We report here homologous recombination An Benefit Of Hypoxia-inducible factors(HIF) (HR)-mediated gene focusing on of two different genes in human PS cells (hiPSCs) and human ES cells (hESCs). HR-mediated correction of a chromosomally integrated mutant GFP reporter gene reaches efficiencies of 0.14%-0.24% in the two cell types transfected by donor DNA with plasmids expressing zinc finger nucleases (ZFNs). Engineered ZFNs that induce a sequence-specific double-strand break inside the GFP gene enhanced HR-mediated correction by > 1400-fold without detectable One particular Advantage Of Seliciclib alterations in stem cell karyotypes or pluripotency. Efficient HR-mediated insertional mutagenesis was also achieved at the endogenous PIG-A locus, with a > 200-fold enhancement by ZFNs targeted to that gene. Clonal PIG-A null hESCs and iPSCs with normal karyotypes were readily obtained. The phenotypic and biological defects were rescued by PIG-A transgene expression. Our study provides the first demonstration of HR-mediated gene targeting in hiPSCs and shows the power of Our Appeal Of Hypoxia-inducible factors(HIF) ZFNs for inducing unique genetic modifications in hiPSCs, as well as hESCs.