X-inactivation profile reveals extensive variability in X-linked gene expression in females.

Published

Journal Article

In female mammals, most genes on one X chromosome are silenced as a result of X-chromosome inactivation. However, some genes escape X-inactivation and are expressed from both the active and inactive X chromosome. Such genes are potential contributors to sexually dimorphic traits, to phenotypic variability among females heterozygous for X-linked conditions, and to clinical abnormalities in patients with abnormal X chromosomes. Here, we present a comprehensive X-inactivation profile of the human X chromosome, representing an estimated 95% of assayable genes in fibroblast-based test systems. In total, about 15% of X-linked genes escape inactivation to some degree, and the proportion of genes escaping inactivation differs dramatically between different regions of the X chromosome, reflecting the evolutionary history of the sex chromosomes. An additional 10% of X-linked genes show variable patterns of inactivation and are expressed to different extents from some inactive X chromosomes. This suggests a remarkable and previously unsuspected degree of expression heterogeneity among females.

Full Text

Cited Authors

  • Carrel, L; Willard, HF

Published Date

  • March 2005

Published In

Volume / Issue

  • 434 / 7031

Start / End Page

  • 400 - 404

PubMed ID

  • 15772666

Pubmed Central ID

  • 15772666

Electronic International Standard Serial Number (EISSN)

  • 1476-4687

International Standard Serial Number (ISSN)

  • 0028-0836

Digital Object Identifier (DOI)

  • 10.1038/nature03479

Language

  • eng