A cross-species comparison of X-chromosome inactivation in Eutheria

Genomics. 2007 Oct;90(4):453-63. doi: 10.1016/j.ygeno.2007.07.002. Epub 2007 Aug 28.


Mammalian X-chromosome inactivation achieves dosage compensation between the sexes by the silencing of one X chromosome in females. In Eutheria, X inactivation is initiated by the large noncoding RNA Xist; however, it is unknown how this RNA results in silencing of the chromosome or why, at least in humans, many genes escape silencing in somatic cells. We have sequenced the coast mole Xist gene and compared the Xist RNA sequence among seven eutherians to provide insight into the structure of the RNA and origins of the gene. Using DNA methylation of promoter sequences to assess whether genes are silenced in females we report the inactivation status of seven X-linked genes in humans and mice as well as two additional eutherians, the mole and the cow, providing evidence that escape from inactivation is common among Eutheria.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Base Sequence
  • Cats
  • Cattle
  • Cells, Cultured
  • Dogs
  • Evolution, Molecular
  • Female
  • Genes, X-Linked
  • Genetic Speciation*
  • Humans
  • Male
  • Mammals / genetics*
  • Mice
  • Models, Biological
  • Molecular Sequence Data
  • Moles / genetics
  • Nucleic Acid Conformation
  • RNA, Long Noncoding
  • RNA, Untranslated / genetics
  • Rats
  • Sequence Homology, Nucleic Acid
  • Species Specificity
  • X Chromosome Inactivation / genetics*
  • X Chromosome Inactivation / physiology*


  • RNA, Long Noncoding
  • RNA, Untranslated
  • XIST non-coding RNA

Associated data

  • GENBANK/DQ845733