Unlike the major autoantigen-(pro)insulin, the role of GAD65 and IA-2 in initiating T1DM in NOD mice remains controversial as a result of the knockout studies and the corresponding autoantibodies analysis (Bonifacio et al., 2001; Lieberman & DiLorenzo, 2003; Kubosaki et al., 2004; DiLorenzo, 2011). Here, GAD2 is linked to type 1 diabetes mellitus.