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The information on this page was automatically extracted from online scientific databases.

What is the official name of the CIITA gene?

The official name of this gene is “class II, major histocompatibility complex, transactivator.”

CIITA is the gene's official symbol. The CIITA gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the CIITA gene?

From NCBI GeneThis link leads to a site outside Genetics Home Reference.:

This gene encodes a protein with an acidic transcriptional activation domain, 4 LRRs (leucine-rich repeats) and a GTP binding domain. The protein is located in the nucleus and acts as a positive regulator of class II major histocompatibility complex gene transcription, and is referred to as the "master control factor" for the expression of these genes. The protein also binds GTP and uses GTP binding to facilitate its own transport into the nucleus. Once in the nucleus it does not bind DNA but rather uses an intrinsic acetyltransferase (AT) activity to act in a coactivator-like fashion. Mutations in this gene have been associated with bare lymphocyte syndrome type II (also known as hereditary MHC class II deficiency or HLA class II-deficient combined immunodeficiency), increased susceptibility to rheumatoid arthritis, multiple sclerosis, and possibly myocardial infarction. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Nov 2013]

From UniProtThis link leads to a site outside Genetics Home Reference.:

Essential for transcriptional activity of the HLA class II promoter; activation is via the proximal promoter. No DNA binding of in vitro translated CIITA was detected. May act in a coactivator-like fashion through protein-protein interactions by contacting factors binding to the proximal MHC class II promoter, to elements of the transcription machinery, or both. Alternatively it may activate HLA class II transcription by modifying proteins that bind to the MHC class II promoter. Also mediates enhanced MHC class I transcription; the promoter element requirements for CIITA-mediated transcription are distinct from those of constitutive MHC class I transcription, and CIITA can functionally replace TAF1 at these genes. Exhibits intrinsic GTP-stimulated acetyltransferase activity. Exhibits serine/threonine protein kinase activity: can phosphorylate the TFIID component TAF7, the RAP74 subunit of the general transcription factor TFIIF, histone H2B at 'Ser-37' and other histones (in vitro).

How are changes in the CIITA gene related to health conditions?

Genetics Home Reference provides information about autoimmune Addison disease, which is associated with changes in the CIITA gene.
UniProtThis link leads to a site outside Genetics Home Reference. provides the following information about the CIITA gene's known or predicted involvement in human disease.

Bare lymphocyte syndrome 2 (BLS2): A severe combined immunodeficiency disease with early onset. It is characterized by a profound defect in constitutive and interferon-gamma induced MHC II expression, absence of cellular and humoral T-cell response to antigen challenge, hypogammaglobulinemia and impaired antibody production. The consequence include extreme susceptibility to viral, bacterial and fungal infections. The disease is caused by mutations affecting the gene represented in this entry.

NCBI GeneThis link leads to a site outside Genetics Home Reference. lists the following diseases or traits (phenotypes) known or believed to be associated with changes in the CIITA gene.
  • Rheumatoid arthritis
  • SCID due to absent class II HLA antigens
OMIM.orgThis link leads to a site outside Genetics Home Reference., a catalog designed for genetics professionals and researchers, provides the following information about the CIITA gene and its association with health conditions.

Where is the CIITA gene located?

Cytogenetic Location: 16p13

Molecular Location on chromosome 16: base pairs 10,866,211 to 10,941,448

The CIITA gene is located on the short (p) arm of chromosome 16 at position 13.

The CIITA gene is located on the short (p) arm of chromosome 16 at position 13.

More precisely, the CIITA gene is located from base pair 10,866,211 to base pair 10,941,448 on chromosome 16.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about CIITA?

You and your healthcare professional may find the following resources about CIITA helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the CIITA gene or gene products?

  • C2TA
  • MHC2TA
  • NLRA

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding CIITA?


The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? in the Handbook.

Published: September 28, 2015