Current Allergy and Asthma Reports

, Volume 13, Issue 6, pp 613–621 | Cite as

Understanding the Role of Tbx1 as a Candidate Gene for 22q11.2 Deletion Syndrome

  • Shan Gao
  • Xiao Li
  • Brad A. AmendtEmail author
Immune Deficiency and Dysregulation (DP Huston, Section Editor)


22q11.2 deletion syndrome (22q11.2DS) is caused by a commonly occurring microdeletion on chromosome 22. Clinical findings include cardiac malformations, thymic and parathyroid hypoplasia, craniofacial dysmorphisms, and dental defects. These phenotypes are due mainly to abnormal development of the pharyngeal apparatus. Targeted deletion studies in mice and analysis of naturally occurring mutations in humans have implicated Tbx1 as a candidate gene for 22q11.2DS. Tbx1 belongs to an evolutionarily conserved T-box family of transcription factors, whose expression is precisely regulated during embryogenesis, and it appears to regulate the proliferation and differentiation of various progenitor cells during organogenesis. In this review, we discuss the mechanisms of Tbx1 during development of the heart, thymus and parathyroid glands, as well as during formation of the palate, teeth, and other craniofacial features.


22q11.2 Deletion syndrome DiGeorge syndrome Velocardiofacial syndrome Tbx1 Pharyngeal apparatus Cardiovascular Pharyngeal arch artery Odontogenesis Palatogenesis Proliferation Craniofacial Thymus Parathyroid Differentiation Candidate gene 



Support for this work was provided from grants DE013941 and DE018885 from the National Institute of Dental and Craniofacial Research. We thank members of the Amendt laboratory for helpful discussions and Christine Blaumueller for editorial expertise.

Compliance with Ethics Guidelines

Conflict of Interest

Shan Gao, Xiao Li, and Brad A. Amendt declare that they have no conflict of interest.

Human and Animal Rights and Informed Consent

This article does not contain any studies with human subjects performed by any of the authors. With regard to the author’s research cited in this paper, all institutional and national guidelines for the care and use of laboratory animals were followed.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Institute of Biosciences and TechnologyTexas A&M University Health Science CenterHoustonUSA
  2. 2.Department of Anatomy and Cell BiologyThe University of IowaIowa CityUSA
  3. 3.The Craniofacial Anomalies Research CenterThe University of IowaIowa CityUSA
  4. 4.Department of Anatomy and Cell Biology, Colleges of Medicine and Dentistry, Craniofacial Anomalies Research CenterThe University of IowaIowa CityUSA

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