X‐chromosome Inactivation and Disease

Abstract

X‐chromosome inactivation is the phenomenon in which one of the two X chromosomes in every somatic cell of female mammals becomes transcriptionally inactive early in embryonic development. This has the result of equalizing the effective gene dosage of X‐linked genes in chromosomally XX females and XY males, and is hence known as a dosage‐compensation mechanism. In humans, X‐chromosome inactivation has implications for the effects seen in diseases due either to X‐linked genes or to numerical or structural anomalies of the X‐chromosome.

Keywords: X‐linked diseases; X‐chromosome aneuploidy; X‐autosome translocations; XIST gene; X‐inactivation centre

References

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Further Reading

Avner P and Heard E (2001) X‐ chromosome inactivation: counting, choice and initiation. Nature Reviews Genetics 2: 58–67.

Belmont JW (1996) Genetic control of X inactivation and processes leading to X inactivation skewing. American Journal of Human Genetics 58: 1101–1108.

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How to Cite close
Lyon, Mary F(Jul 2007) X‐chromosome Inactivation and Disease. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0005480.pub2]