Title: sex chromatin
Long Title: IUPAC Gold Book - sex chromatin
DOI: 10.1351/goldbook.11210
Status: current

Definition
Condensed mass of one inactivated X chromosome seen inside the nuclear membrane of an interphase cell.

Note
The Barr body is not seen in normal male cells (XY), but one body may be seen in normal female cells (XX). In chromosomal abnormalities, the number seen is one less than the number of X chromosomes.

Related Terms
- Lyon hypothesis: https://goldbook.iupac.org//terms/view/10906
- X chromosome: https://goldbook.iupac.org//terms/view/11385
- chromosomal: https://goldbook.iupac.org//terms/view/10524
- membrane: https://goldbook.iupac.org//terms/view/11555

Source
- PAC, 2016, 88, 713. 'Glossary of terms used in developmental and reproductive toxicology (IUPAC Recommendations 2016)' on page 804 (https://doi.org/10.1515/pac-2015-1202)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/11210/html
- json: https://goldbook.iupac.org/terms/view/11210/json
- xml: https://goldbook.iupac.org/terms/view/11210/xml

Citation: Citation: 'sex chromatin' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.11210
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Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2025-09-10T20:21:53+00:00