PTPRN and type 1 diabetes mellitus: The immunological markers of type 1 diabetes include antibodies active against pancreatic β cells: Islet-cell antibodies (ICA), insulin autoantibodies (IAA), anti-glutamine acid decarboxylase (anti-GAD), anti-zinc transporter protein 8 (anti-ZnT8), and anti-tyrosine phosphatase antibodies (anti-IA2) [89].