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GTF2I gene

general transcription factor IIi

Normal Function

The GTF2I gene provides instructions for making two proteins, TFII-I and BAP-135. TFII-I attaches (binds) to specific areas of DNA and helps regulate the activity of other genes. Based on this role, TFII-I is called a transcription factor. This protein is active in the brain and many other tissues in the body. Studies suggest that the TFII-I protein is involved in coordinating cell growth and division, and it may also play a role in controlling the flow of calcium into cells. Studies show it may be important in a process called myelination, which is the formation of the protective coating around nerve cells called the myelin sheath. This coating insulates nerve cells and promotes the rapid transmission of nerve impulses.

Less is known about BAP-135, the other protein produced from the GTF2I gene. The protein is active in B cells, which are a specialized type of white blood cell that protects the body against infection. When a B cell senses a foreign substance (such as a virus), it triggers a series of chemical reactions that instruct the cell to mature, divide, and produce specific proteins called antibodies to fight the infection. The BAP-135 protein is turned on as part of this series of chemical reactions.

Health Conditions Related to Genetic Changes

7q11.23 duplication syndrome

The GTF2I gene is located in a region of chromosome 7 that is duplicated in people with 7q11.23 duplication syndrome. As a result of this duplication, people with 7q11.23 duplication syndrome have an extra copy of the GTF2I gene and several other genes in each cell. 7q11.23 duplication syndrome can cause a variety of neurological and behavioral problems as well as other abnormalities.

Behavioral problems associated with 7q11.23 duplication syndrome include anxiety disorders (such as social phobias and selective mutism, which is an inability to speak in certain circumstances), attention-deficit/hyperactivity disorder (ADHD), physical aggression, excessively defiant behavior (oppositional disorder), and autistic behaviors that affect communication and social interaction. Studies suggest that an extra copy of the GTF2I gene may be associated with some of the behavioral features of 7q11.23 duplication syndrome, but the mechanism of this effect is unclear. Affected individuals do not appear to have immune abnormalities related to this disorder.

More About This Health Condition

Williams syndrome

The GTF2I gene is located in a region of chromosome 7 that is missing (deleted) in people with Williams syndrome, which is a developmental disorder characterized by mild to moderate intellectual disability or learning problems, unique personality characteristics, distinctive facial features, and heart and blood vessel (cardiovascular) problems. As a result of the deletion, people with Williams syndrome are missing one copy of the GTF2I gene in each cell. 

Studies suggest that the loss of this gene is partly responsible for intellectual disability in people with Williams syndrome.  Loss of this gene may also contribute to behavioral differences, such as increased sociability and anxiety-related behaviors, that are seen in this disorder. Studies show that some affected individuals have less myelin than normal in some parts of their brains, and researchers suspect reduced myelination may contribute to the behavioral features. Researchers are investigating how changes in this gene may be related to these and other specific features of Williams syndrome. People with Williams syndrome do not appear to have immune abnormalities related to the condition.

More About This Health Condition

Other Names for This Gene

  • BAP-135
  • BAP135
  • Bruton tyrosine kinase-associated protein 135
  • BTK-associated protein, 135kD
  • BTKAP1
  • DIWS
  • IB291
  • SPIN
  • TFII-I
  • WBSCR6

Additional Information & Resources

Tests Listed in the Genetic Testing Registry

Scientific Articles on PubMed

Catalog of Genes and Diseases from OMIM

Gene and Variant Databases


  • Barak B, Zhang Z, Liu Y, Nir A, Trangle SS, Ennis M, Levandowski KM, Wang D, Quast K, Boulting GL, Li Y, Bayarsaihan D, He Z, Feng G. Neuronal deletion of Gtf2i, associated with Williams syndrome, causes behavioral and myelin alterations rescuable by a remyelinating drug. Nat Neurosci. 2019 May;22(5):700-708. doi: 10.1038/s41593-019-0380-9. Epub 2019 Apr 22. Erratum In: Nat Neurosci. 2019 Jul;22(7):1197. doi: 10.1038/s41593-019-0441-0. Citation on PubMed
  • Caraveo G, van Rossum DB, Patterson RL, Snyder SH, Desiderio S. Action of TFII-I outside the nucleus as an inhibitor of agonist-induced calcium entry. Science. 2006 Oct 6;314(5796):122-5. doi: 10.1126/science.1127815. Citation on PubMed
  • Danoff SK, Taylor HE, Blackshaw S, Desiderio S. TFII-I, a candidate gene for Williams syndrome cognitive profile: parallels between regional expression in mouse brain and human phenotype. Neuroscience. 2004;123(4):931-8. doi: 10.1016/j.neuroscience.2003.08.038. Citation on PubMed
  • Egloff AM, Desiderio S. Identification of phosphorylation sites for Bruton's tyrosine kinase within the transcriptional regulator BAP/TFII-I. J Biol Chem. 2001 Jul 27;276(30):27806-15. doi: 10.1074/jbc.M103692200. Epub 2001 May 23. Citation on PubMed
  • Hirota H, Matsuoka R, Chen XN, Salandanan LS, Lincoln A, Rose FE, Sunahara M, Osawa M, Bellugi U, Korenberg JR. Williams syndrome deficits in visual spatial processing linked to GTF2IRD1 and GTF2I on chromosome 7q11.23. Genet Med. 2003 Jul-Aug;5(4):311-21. doi: 10.1097/01.GIM.0000076975.10224.67. Citation on PubMed
  • Kozel BA, Barak B, Kim CA, Mervis CB, Osborne LR, Porter M, Pober BR. Williams syndrome. Nat Rev Dis Primers. 2021 Jun 17;7(1):42. doi: 10.1038/s41572-021-00276-z. Citation on PubMed
  • Makeyev AV, Bayarsaihan D. New TFII-I family target genes involved in embryonic development. Biochem Biophys Res Commun. 2009 Sep 4;386(4):554-8. doi: 10.1016/j.bbrc.2009.06.045. Epub 2009 Jun 13. Citation on PubMed
  • Martin LA, Iceberg E, Allaf G. Consistent hypersocial behavior in mice carrying a deletion of Gtf2i but no evidence of hyposocial behavior with Gtf2i duplication: Implications for Williams-Beuren syndrome and autism spectrum disorder. Brain Behav. 2017 Dec 19;8(1):e00895. doi: 10.1002/brb3.895. eCollection 2018 Jan. Citation on PubMed
  • Mervis CB, Klein-Tasman BP, Huffman MJ, Velleman SL, Pitts CH, Henderson DR, Woodruff-Borden J, Morris CA, Osborne LR. Children with 7q11.23 duplication syndrome: psychological characteristics. Am J Med Genet A. 2015 Jul;167(7):1436-50. doi: 10.1002/ajmg.a.37071. Epub 2015 Apr 21. Citation on PubMed or Free article on PubMed Central
  • Meyer-Lindenberg A, Mervis CB, Berman KF. Neural mechanisms in Williams syndrome: a unique window to genetic influences on cognition and behaviour. Nat Rev Neurosci. 2006 May;7(5):380-93. doi: 10.1038/nrn1906. Citation on PubMed
  • Morris CA, Mervis CB, Hobart HH, Gregg RG, Bertrand J, Ensing GJ, Sommer A, Moore CA, Hopkin RJ, Spallone PA, Keating MT, Osborne L, Kimberley KW, Stock AD. GTF2I hemizygosity implicated in mental retardation in Williams syndrome: genotype-phenotype analysis of five families with deletions in the Williams syndrome region. Am J Med Genet A. 2003 Nov 15;123A(1):45-59. doi: 10.1002/ajmg.a.20496. Citation on PubMed
  • Perez Jurado LA, Wang YK, Peoples R, Coloma A, Cruces J, Francke U. A duplicated gene in the breakpoint regions of the 7q11.23 Williams-Beuren syndrome deletion encodes the initiator binding protein TFII-I and BAP-135, a phosphorylation target of BTK. Hum Mol Genet. 1998 Mar;7(3):325-34. doi: 10.1093/hmg/7.3.325. Citation on PubMed
  • Roy AL. Signal-induced functions of the transcription factor TFII-I. Biochim Biophys Acta. 2007 Nov-Dec;1769(11-12):613-21. doi: 10.1016/j.bbaexp.2007.10.002. Epub 2007 Oct 11. Citation on PubMed or Free article on PubMed Central
  • Sakurai T, Dorr NP, Takahashi N, McInnes LA, Elder GA, Buxbaum JD. Haploinsufficiency of Gtf2i, a gene deleted in Williams Syndrome, leads to increases in social interactions. Autism Res. 2011 Feb;4(1):28-39. doi: 10.1002/aur.169. Epub 2010 Dec 3. Citation on PubMed
  • Tassabehji M. Williams-Beuren syndrome: a challenge for genotype-phenotype correlations. Hum Mol Genet. 2003 Oct 15;12 Spec No 2:R229-37. doi: 10.1093/hmg/ddg299. Epub 2003 Sep 2. Citation on PubMed
  • Yang W, Desiderio S. BAP-135, a target for Bruton's tyrosine kinase in response to B cell receptor engagement. Proc Natl Acad Sci U S A. 1997 Jan 21;94(2):604-9. doi: 10.1073/pnas.94.2.604. Citation on PubMed or Free article on PubMed Central

The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.