Barr body
Corpúsculo de Barr
- Date
- 1949 · confidence high
- Place
- University of Western Ontario, London, Ontario, Canada
- Credited to
- Murray Barr and Ewart Bertram
- Field
- Life & health
What was discovered
Barr and his student Bertram observed under the microscope, in the nucleus of female cat somatic cells, a condensed mass of chromatin -the inactive X chromosome- absent in males: the first visible evidence of gene dosage compensation.
Emil Heitz's 1928 work on heterochromatin and euchromatin provided the conceptual basis for interpreting the body.
What it led to
- Buccal smear test to determine chromosomal sex (Barr and Moore, 1955)
- Lyon hypothesis of X-chromosome inactivation (Mary Lyon, 1961)
- Clinical screening for chromosomal abnormalities