Linked Life Data

12572852

Source:http://linkedlifedata.com/resource/pubmed/id/12572852

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
439
pubmed:dateCreated
2003-2-7
pubmed:abstractText
The inactivation of one X-chromosome in females in early development is the process by which the effective dosage of X-linked genes is equalized between XX females and XY males. The mechanism that brings this about is the subject of intense research. The X-linked gene Xist is a key player, which is necessary but not sufficient for the initiation of X-inactivation. It codes for an untranslated RNA that coats the inactive X-chromosome, which takes on properties characteristic of heterochromatin, but how this change in chromatin is brought about remains unknown. Because of X-inactivation, females heterozygous for X-linked genes are mixtures of two types of cells and show a variable phenotype. The proportions of the two types of cells can depart from equality due to cell selection either at the tissue or whole organism level. In rare cases, changes in the Xist gene can cause skewing of X-inactivation. A few genes escape from X-inactivation either wholly or partially. CONCLUSION: X-chromosome inactivation is a physiological mechanism that equalizes gene-dosage effects on the sex chromosomes. The occurrence of this normal process affects the phenotype seen in females carrying X-linked mutant genes or chromosome anomalies.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0803-5326
pubmed:author
pubmed:issnType
Print
pubmed:volume
91
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
107-12
pubmed:dateRevised
2008-5-12
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
X-chromosome inactivation and human genetic disease.
pubmed:affiliation
MRC Mammalian Genetics Unit, Harwell, Didcot, Oxfordshire, UK. m.lyon@har.mrc.ac.uk
pubmed:publicationType
Journal Article, Review