This was first evidenced in mice lacking the Foxp3 gene, which resulted in massive systemic autoimmune inflammation [1] and has also been observed in humans with loss-of-function mutations in the FOXP3 gene, which causes immune dysregulation, polyendocrinopathy, enteropathy, and X-linked (IPEX) syndrome [2]. Here, FOXP3 is linked to polyendocrinopathy.