The action of three anticlastogens on the induction of sister chromatid exchange by trenimon and 8-hydroxyquinoline sulfate in human lymphocyte cultures.

The influence of the anticlastogens beta-aminoethylisothiouronium (AET), d,l-homocysteinethiolactone (HCT), and 1-cysteine (CYS) on the frequency of sister chromatid exchanges (SCEs) induced by the chromosome damaging chemicals Trenimon and 8-hydroxyquinoline sulfate (8-HQS), was investigated in human lymphocyte cultures. None of the anticlastogens significantly influenced the SCE rate, whereas in the same or previous experiments the chromosome-breaking effect of these clastogens was distinctly reduced by the anticlastogens. These results suggest that the sites of anticlastogenic activity do not coincide with the sites of SCE formation. SCE analysis, although it yields interesting and important information about the action of chemicals on genetic material, cannot replace classical aberration analysis, because the two parameters apparently reflect different patterns of molecular and cytogenetic activity of mutagens.