It is the most common aetiology of primary adrenal insufficiency in developed countries (2) and the condition can occur in isolation or as a component of autoimmune polyendocrine syndrome types 1 (APS-1) or 2 (APS-2), the former being a monogenic disorder caused by mutations in the AIRE gene (3). The gene discussed is AIRE; the disease is autoimmune polyendocrine syndrome type 1.