The effect of aphidicolin on Fanconi's anemia lymphocyte chromosomes.

The cytogenetic effect of the DNA polymerase alpha inhibitor aphidicolin (APC) at a dose which did not affect cell cycle progression was determined in normal and Fanconi's anemia (FA) lymphocytes. APC enhanced sister-chromatid exchange (SCE) levels by about twice both in control and FA cells, while the yields of chromosome breakage increased up to 20 times in normal lymphocytes and 4 times in FA cells. APC did not act synergistically with the bifunctional alkylating diepoxybutane in terms of SCE either in normal or in FA lymphocytes. However, chromosome aberrations in cultures from normal subjects were much more than expected by an additive mode of action.