More recently, an allelic series of isogenic hPSCs with endogenous heterozygous or homozygous expression of the PI3Kα-activating cancer-driver mutation PIK3CAH1047R were shown to exhibit a striking allele dose-dependent stemness phenotype [59] — similar to the aforementioned findings with heterozygous versus homozygous loss of Pten in mESCs. Here, PTEN is linked to cancer.