The association of the CTLA-4 gene with several autoimmune diseases such as T1D [153,169], Addison's disease [191,192], multiple sclerosis [193,194], myasthenia gravis [175] and all clinical outcomes of AITD [74], can also explain the general contribution of CTLA-4 to autoimmunity. This evidence concerns the gene CTLA4 and type 1 diabetes mellitus.