Normal response of Fanconi's anemia cells to high concentrations of O 2 as determined by alkaline elution

Abstract

In this investigation, normal and Fanconi's anemia fibroblasts were exposed to high concentrations of oxygen and the effects of this treatment on DNA were analyzed by alkaline elution. No DNA single-strand breaks were detected in either cell type with up to 20 h incubation in high (50–95%) concentrations of O 2. No evidence of DNA damage by O 2 could be detected with an endonuclease preparation from Micrococcus luteus. Cells which have been treated with various DNA-damaging agents in the presence of the polymerase inhibitor cytosine arabinoside have been shown to accumulate DNA single-strand breaks during DNA excision repair. When cells were treated with the polymerase inhibitor in 50 or 95% O 2, a low level of DNA single-strand breaks accumulated in both cell types. However, no significant differences in the frequency of DNA single-strand breaks were detected between normal and Fanconi's anemia cells after exposure to high O 2.