The same has been observed for other genes involved in the immune response, such as BLK proto-oncogene (BLK) [34], Interferon regulatory factor 5 (IRF5), and Protein tyrosine phosphatase non-receptor type 22 (PTPN22), even if the role of these two latter genes in APS remains still controversial [35,36,37]. The gene discussed is PTPN22; the disease is autoimmune polyendocrinopathy.