Human Genetics

, Volume 126, Issue 3, pp 363–373 | Cite as

X chromosome inactivation in clinical practice

  • Karen Helene ØrstavikEmail author
Review Article


X chromosome inactivation (XCI) is the transcriptional silencing of the majority of genes on one of the two X chromosomes in mammalian females. Females are, therefore, mosaics for two cell lines, one with the maternal X and one with the paternal X as the active chromosome. The relative proportion of the two cell lines, the X inactivation pattern, may be analyzed by simple assays in DNA from available tissues. This review focuses on medical issues related to XCI in X-linked disorders, and on the value of X inactivation analysis in clinical practice.


Fabry Disease Female Carrier Incontinentia Pigmenti Hypohidrotic Ectodermal Dysplasia Preferential Inactivation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



I am thankful to Trine Prescott for critical reading of the manuscript.

Conflict of interest statement



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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.Department of Medical Genetics, Oslo University Hospital, Rikshospitalet and Faculty Division RikshospitaletUniversity of OsloOsloNorway

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