In vivo cytogenetic damage revealed by FISH analysis of micronuclei in uncultured human T lymphocytes.

FISH analysis of micronuclei in uncultured human T lymphocytes provides a convenient new possibility to assess structural and numerical chromosome damage in vivo. In women. T-cell micronuclei mostly contained whole chromosomes (71.6%), especially the X chromosome (28.5%). Cell culture (72 h) enhanced the frequency of micronuclei harboring acentric fragments 2.9 fold and the X chromosome 1.5 fold. X-chromosome-positive micronuclei were particularly prevalent (42.0%) in binucleate cells produced by cytochalasin B, a cytokinesis inhibitor used to identify cells that have divided in vitro. This was explained by a decrease in autosome-containing and an increase in X-positive micronuclei.