Loss-of-function mutations in genes for eIF2B subunits can destabilize the complex, disturb the eIF2B-mediated reloading of GTP onto eIF2, or affect the binding of eIF2(αP), thereby causing translation dysregulations that can result in fatal neurological disorders or neonatal diabetes mellitus (1, 7, 8, 9). The gene discussed is EIF2B5; the disease is neonatal diabetes mellitus.