Chromosome 21<unk>  is caused by a mutation in the AIRE gene, encoding a protein called autoimmune regulator. This is found on the 21q22.3 chromosome location, hence chromosome 21. The AIRE gene may be affected by any of at least 90 mutations. Mutations may be inherited in an autosomal recessive manner. Different mutations are more common in different geographic regions. R139X is a common mutation in Sardinia. R257* is a common mutation in Finland.
Autoimmune polyendocrine syndrome type 1
Autoimmune polyendocrine syndrome type 2
Autoimmune polyendocrine syndrome type 3
Multiple endocrine neoplasia type 1
Multiple endocrine neoplasia type 2
Multiple endocrine neoplasia type 2B
Graves' disease
Addison's disease