In some models of type-2 diabetes, islet architecture is distorted, with intermingling of α and β cells reminiscent of the Neurog3-Cre;Robo1Δ/Δ,2flx/flx and Ins2-Cre;Robo1Δ/Δ,2flx/flx phenotypes12. This evidence concerns the gene NEUROG3 and type 2 diabetes mellitus.