See Also: Barr body(health)
Barr body(medicine)
Barr body(dictionary)
Barr chromatin body(medicine)
Barr Pharmaceuticals(finance)
Barr, Yvonne(medicine)
Barr, Murray(medicine)
Epstein-Barr virus(health)
epstein-barr virus(medicine)
Epstein-Barr virus(dictionary)

Barr body (health)


The color-staining spot (the sex chromatin) located at the edge of the nucleus of cells taken from individuals with more than one X chromosome. It is normally found in female cells, and so is used as a sign of female genetic sex. It is also found in men with the 47,XXY (Klinefelter's) syndrome. It is missing in girls with the 45,X (Turner's) syndrome. The Barr-body test is rapid and inexpensive as compared with actual chromosome counting, and so is used as a method of preliminary X-chromosome screening.