Amendment history : Retraction ( March 2017 ) iPSC-derived b cells model diabetes due to glucokinase deficiency

Diabetes is a disorder characterized by loss of b cell mass and/or b cell function, leading to deficiency of insulin relative to metabolic need. To determine whether stem cell–derived b cells recapitulate molecular-physiological phenotypes of a diabetic subject, we generated induced pluripotent stem cells (iPSCs) from subjects with maturity-onset diabetes of the young type 2 (MODY2), which is characterized by heterozygous loss of function of the gene encoding glucokinase (GCK). These stem cells differentiated into b cells with efficiency comparable to that of controls and expressed markers of mature b cells, including urocortin3 and zinc transporter 8, upon transplantation into mice. While insulin secretion in response to arginine or other secretagogues was identical to that in cells from healthy controls, GCK mutant b cells required higher glucose levels to stimulate insulin secretion. Importantly, this glucose-specific phenotype was fully reverted upon gene sequence correction by homologous recombination. Our results demonstrate that iPSC-derived b cells reflect b cell– autonomous phenotypes of MODY2 subjects, providing a platform for mechanistic analysis of specific genotypes on b cell function. Technical Advance Metabolism