Escape Artists of the X Chromosome

Bradley P Balaton; Carolyn J Brown

doi:10.1016/j.tig.2016.03.007

Escape Artists of the X Chromosome

Trends Genet. 2016 Jun;32(6):348-359. doi: 10.1016/j.tig.2016.03.007. Epub 2016 Apr 18.

Authors

Bradley P Balaton¹, Carolyn J Brown²

Affiliations

¹ Department of Medical Genetics, Molecular Epigenetics Group, University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada.
² Department of Medical Genetics, Molecular Epigenetics Group, University of British Columbia, Vancouver, British Columbia, V6T 1Z3 Canada. Electronic address: carolyn.brown@ubc.ca.

PMID: 27103486
DOI: 10.1016/j.tig.2016.03.007

Abstract

Inactivation of one X chromosome in mammalian females achieves dosage compensation between XX females and XY males; however, over 15% of human X-linked genes continue to be expressed from the inactive X chromosome. New genomic methodologies have improved our identification and characterization of these escape genes, revealing the importance of DNA sequence, chromatin structure, and chromosome ultrastructure in regulating expression from an otherwise inactive chromosome. Study of these exceptions to the rule of silencing highlights the interconnectedness of chromatin and chromosome structure in X-chromosome inactivation (XCI). Recent advances also demonstrate the importance of these genes in sexually dimorphic disease risk, particularly cancer.

Keywords: X chromosome; X-chromosome inactivation; allelic sequence analysis; dosage compensation; epigenetic silencing; sex chromosomes.

Publication types

Review
Research Support, Non-U.S. Gov't

MeSH terms

Animals
Chromatin / genetics
Chromosomes, Human, X / genetics*
DNA Methylation / genetics
Dosage Compensation, Genetic*
Female
Humans
Male
Mammals
X Chromosome Inactivation / genetics*

Substances

Chromatin

Grants and funding

CIHR/Canada