Purpose of Review
Pitt-Hopkins syndrome (PTHS) is a rare neurodevelopmental disorder that results from mutations of the clinically pleiotropic transcription factor 4 (TCF4) gene. Mutations in the genomic locus of TCF4 on chromosome 18 have been linked to multiple disorders including 18q syndrome, schizophrenia, Fuch’s corneal dystrophy, and sclerosing cholangitis. For PTHS, TCF4 mutation or deletion leads to the production of a dominant negative TCF4 protein and/or haploinsufficiency that result in abnormal brain development. The biology of TCF4 has been studied for several years in regard to its role in immune cell differentiation, although its role in neurodevelopment and the mechanisms resulting in the severe symptoms of PTHS are not well studied.
Here, we summarize the current understanding of PTHS and recent findings that have begun to describe the biological implications of TCF4 deficiency during brain development and into adulthood. In particular, we focus on recent work that has looked at the role of TCF4 biology within the context of PTHS and highlight the potential for identification of therapeutic targets for PTHS.
PTHS research continues to uncover mutations in TCF4 that underlie the genetic cause of this rare disease, and emerging evidence for molecular mechanisms that TCF4 regulates in brain development and neuronal function is contributing to a more complete picture of how pathology arises from this genetic basis, with important implications for the potential of future clinical care.
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This work was supported by NIH grant (R56MH104593) and Pitt-Hopkins Research Foundation Award to B.J.M.
Conflict of Interest
Matthew D. Rannals declares that he has no conflict of interest.
Brady J. Maher reports grants from the NIH/NIMH during the conduct of study. He reports employment at the Lieber Institute for Brain Development and grants from NIMH outside of the submitted work.
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This article does not contain any studies with human or animal subjects performed by any of the authors.
This article is part of the Topical Collection on Neurogenetics and Psychiatric Genetics
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Rannals, M.D., Maher, B.J. Molecular Mechanisms of Transcription Factor 4 in Pitt-Hopkins Syndrome. Curr Genet Med Rep 5, 1–7 (2017). https://doi.org/10.1007/s40142-017-0110-0
- Pitt-Hopkins syndrome
- Transcription factor 4
- Autism spectrum