Time will tell whether the knowledge on the specificity of T1D autoantibodies to insulin (INS), 65 kDa glutamic acid decarboxylase (GAD65), insulinoma-associated protein2 (IA2) and zinc transporter 8(Znt8) (30) has helped or derailed the investigation of the β-cell specific targets of T cell autoimmunity (26, 31). Here, GAD2 is linked to type 1 diabetes mellitus.