Barr body


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Related to Barr body: Pseudoautosomal region

Barr body

[′bär ‚bäd·ē]
(cell and molecular biology)
A condensed, inactivated X chromosome inside the nuclear membrane in interphase somatic cells of women and most female mammals. Also known as sex chromatin.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
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References in periodicals archive ?
required by the USTA, to undergo the Barr body test.
Barr body: in 1949 Barr and Bertram noticed a jextanuclear chromatin in the nuclei of all female cells.
Open Committee required all female competitors to verify their gender with a Barr body test, which looks for the presence of two X chromosomes in a somatic cell to prove that the subject is female.
This is driven by the X-inactivation gene (XIST), which produces a noncoding RNA that covers the entire X chromosome and essentially silences it--making it inactive and condensing it into what is termed a Barr body.