PTPN2 has been implicated in the regulation of insulin signaling and glucose homeostasis [18, 19] and is also associated with chronic inflammatory and autoimmune diseases such as rheumatoid arthritis (RA) [20], Crohn's disease [21], periodontitis [22], and type 1 diabetes mellitus (T1DM) [23]. This evidence concerns the gene PTPN2 and type 1 diabetes mellitus.