PTPN22 and type 1 diabetes mellitus: Additionally to HLA genes, several other genes, including the cytotoxic T-lymphocyte associated protein 4 (CTLA4, c.+6230G>A, rs3087243) and (CTLA4, c.49A>G, rs231775), the protein tyrosine phosphatase non-receptor type 22 (PTPN22, c.+1858 C>T, rs2476601), the interleukin 2 receptor subunit alpha (IL2Ra, c.A>G rs10795791), the vitamin D receptor (VDR, Bsm I rs1544410; Apa I rs7975232; Taq I rs731236), as well as the tumor necrosis factor (TNF, c.-863G>A, rs1800630) have been reported as susceptibility genes for T1D and AITD (Table 1).