CISD2 and peptic ulcer disease: Here, we report the identification of a novel homozygous CISD2 mutation (c.215A > G; p.Asn72Ser) in a patient with a “classical” WS phenotype marked by childhood-onset insulin-dependent diabetes mellitus and progressive visual failure secondary to optic atrophy, but without peptic ulcers or defective platelet aggregation as reported previously in affected CISD2 mutation carriers.