Wolframin is a transmembrane protein.Wolframin appears to function as a cation-selective ion channel.Mutations in this gene are associated with an autosomal recessive syndrome characterized by insulin-dependent diabetes mellitus and bilateral progressive optic atrophy, usually presenting in childhood or early adult life. Diverse neurologic symptoms, including a predisposition to psychiatric illness, may also be associated with this disorder. A large number and variety of mutations in this gene, particularly in exon 8, can be associated with this syndrome. Mutations in this gene can also cause autosomal dominant deafness 6 (DFNA6).Highly expressed in heart followed by brain, placenta, lung and pancreas. Weakly expressed in liver, kidney and skeletal muscle. Also expressed in islet and beta-cell insulinoma cell line.