X‐chromosome Inactivation and Disease


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


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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.

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Plath K, Mlynarczyil‐Evans S, Nusinow DA and Panning B (2002) XIST RNA and the mechanism of X‐chromosome inactivation. Annual Review of Genetics 36: 233–278.

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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]