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Yasin et al. J Transl Genet Genom 2020;4:307-19 Journal of Translational
DOI: 10.20517/jtgg.2020.30 Genetics and Genomics

Review Open Access

Chromodomain helicase DNA-binding proteins and
neurodevelopmental disorders

Heba Yasin , Farah R. Zahir 2
1
1 College of Health and Life Sciences, Hamad Bin Khalifa University, Doha 34110, Qatar.
2 Department of Medical Genetics, University of British Columbia, Vancouver, BC V6H 3N1, Canada.
Correspondence to: Dr. Farah R. Zahir, Department of Medical Genetics, University of British Columbia, Box 153, Children’s and
Women’s Hospital, 4500 Oak Street, Vancouver, BC V6H 3N1, Canada. E-mail: farahz@bcchr.ca
How to cite this article: Yasin H, Zahir FR. Chromodomain helicase DNA-binding proteins and neurodevelopmental disorders. J
Transl Genet Genom 2020;4:307-19. http://dx.doi.org/10.20517/jtgg.2020.30
Received: 15 Apr 2020 First Decision: 20 May 2020 Revised: 26 May 2020 Accepted: 28 May 2020 Available online: 18 Aug 2020
Academic Editor: Tjitske Kleefstra Copy Editor: Cai-Hong Wang Production Editor: Tian Zhang

Abstract
The significance of epigenomic regulation is now established in the etiology of neurodevelopmental disorders
(NDDs). Epigenomic regulatory processes include chromatin remodeling as a major regulator of gene expression in
development. Chromatin remodeling is an enzymatic process carried out by large multi-unit protein complexes, of
which the chromodomain helicase DNA-binding proteins comprise one of four recognized major protein families,
named the chromodomain helicase DNA-binding (CHD) family. There are nine CHD proteins (CHD1-9) encoded by
nine correspondingly named CHD genes. Remarkably, five of the nine CHDs are already recognized to be causative
of autosomal dominant syndromic NDD. In this review, we discuss the contribution of all CHDs to NDDs. And, we
specifically focus on molecular studies involving CHD8 of which several have been recently published and scarcely
reviewed. The widespread nature of downstream targeting for CHD8, as well as the finding of autosomal dominant
disease for the majority of CHDs in general, implicates this family of chromatin remodelers as major players in NDD
causation.

Keywords: CHD8, intellectual disability, neurodevelopmental disorders, autism spectrum disorder, CHDs,
chromodomain helicase DNA-binding proteins, epigenomics, epigenetics

INTRODUCTION
Introduction to epigenetics
The term epigenetics was initially introduced in 1942 as a means to describe hereditary (i.e., “genetic”)
[1]
processes that were not explained by classical genetics . While several epigenetic processes are now being
defined both conceptually and mechanistically, the core idea remains the same, that is, gene function

© The Author(s) 2020. Open Access This article is licensed under a Creative Commons Attribution 4.0
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