FOXP3 and type 1 diabetes mellitus: The rare genetic poly-autoimmune syndromes immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome (FOXP3 mutations) and autoimmune polyendocrinopathy, candidiasis, ectodermal dystrophy (APECED) syndrome (AIRE mutations) affect T cell tolerance mechanisms and can comprise type 1 diabetes.