From Genetic Predisposition to Molecular Mechanisms of Autoimmune Primary Adrenal Insufficiency

Autoimmune Addison's disease (AAD) is a complex disease that results from the interaction of a predisposing genetic background with still unknown environmental factors. Pathogenic variants in the autoimmune regulator (AIRE) gene are responsible for autoimmune polyendocrine syndrome type 1, of which AAD is a major disease component. Among the genetic factors for isolated AAD and autoimmune polyendocrine syndrome type 2, a key role is played by HLA class II genes: HLA-DRB1*0301-DQA1*0501-DQB1*0201 and DRB1*04-DQA1*0301-DQB1*0302 are positively, and DRB1*0403 is negatively, associated with genetic risk for AAD. The MHC class I chain-related gene A (MICA) allele 5.1 is strongly and positively associated with AAD. Other gene polymorphisms contribute to the genetic risk for AAD, including CIITA (MHC class II transactivator), the master regulator of MHC class II expression, cytotoxic T-lymphocyte antigen-4 (CTLA-4), PTPN22, STAT4, PD-L1, NALP1, FCRL3, GPR174, GATA3, NFATC1, CYP27B1 and the vitamin D receptor.