In addition to the HLA region, the insulin (INS), cytotoxic T lymphocyte-associated protein 4 (CTLA-4), IL-2 receptor (IL2RA), and protein tyrosine phosphatase N 22 (PTPN22) genes have the most significant influences on the etiopathogenesis of T1D [5,6]. Here, CTLA4 is linked to type 1 diabetes mellitus.