PTPRN and type 1 diabetes mellitus: These receptors are homologous to mammalian IA-2 (Insulinoma Associated protein-2)/ICA-512, and IA-2β (phogrin) that act as type1 diabetes (insulin dependent diabetes) auto antigen, i.e. they are considered as markers of the disease and auto antibodies are expressed prior to the appearance of clinical symptoms of the disease [7], [8].