forkhead box P3
The FOXP3 gene provides instructions for producing the forkhead box P3 (FOXP3) protein. The FOXP3 protein attaches (binds) to specific regions of DNA and helps control the activity of genes that are involved in regulating the immune system. On the basis of this role, the FOXP3 protein is called a transcription factor. This protein is essential for the production and normal function of certain immune cells called regulatory T cells, which play an important role in preventing autoimmunity. Autoimmunity occurs when the body attacks its own tissues and organs by mistake. The FOXP3 protein is found primarily in an immune system gland called the thymus, where regulatory T cells are produced.
At least 21 mutations in the FOXP3 gene have been found to cause immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome. Most mutations change one protein building block (amino acid) in the region of the FOXP3 protein that binds to DNA or lead to the production of an abnormally short, nonfunctional protein. Mutations in the FOXP3 gene result in reduced numbers or a complete absence of regulatory T cells. Without the proper number of regulatory T cells, the body cannot control immune responses. Normal body tissues and organs are attacked, causing the multiple autoimmune disorders present in people with IPEX syndrome.
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- immune dysregulation, polyendocrinopathy, enteropathy, X-linked
- immunodeficiency, polyendocrinopathy, enteropathy, X-linked