title: X chromosome inactivation in clinical practice.
abstract: 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.
authors.affiliation: Department of Medical Genetics, Oslo University Hospital, Rikshospitalet and Faculty Division Rikshospitalet, University of Oslo, Forskningsveien 2B, 0027, Oslo, Norway. k.h.orstavik@medisin.uio.no
authors.forename: Karen Helene
authors.initials: KH
authors.lastname: Orstavik
mesh_terms: D000293:Adolescent; D000328:Adult; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D041321:Chromosomes, Human, X / Q000648:ultrastructure*; D005260:Female; D020868:Gene Silencing; D040181:Genetic Diseases, X-Linked / Q000235:genetics; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010641:Phenotype; D049951:X Chromosome Inactivation