Some studies suggest that certain non-HLA genes, such as cytotoxic T-lymphocyte associated protein 4 (CTLA-4), interferon induced with helicase C domain 1 (IFIH1), lymphoid protein tyrosine phosphatase, non-receptor type 22 (PTPN22), insulin (INS), vitamin D receptor (VDR), interleukin 2 receptor alpha (IL2RA), KIAA0350 and phosphotyrosine protein phosphatase, non-receptor 2 (PTPN2), may be associated with T1D [3]. This evidence concerns the gene PTPN22 and type 1 diabetes mellitus.