A search for storage effects on chromosome aberrations induced in human normal type- and xeroderma pig-mentosum fibroblasts by tetra-ethylene-imino-1,4-benzochinon and n-acetoxy-n-2-acetylaminofluorene.

Normal human foreskin fibroblasts in stationary phase were treated with tetra-ethylene-imino-1,4-benzochinon. Treated cells were stored for 0, 1, 2 or 3 weeks on special storage medium and then analyzed for induced chromosome aberrations. The results showed that there was a decrease in the frequency of chromosome aberrations with increasing storage times rather than an increase. These observations may indicate that, (1) a storage effect of the type observed in Drosophila, Neurospora and barley (i.e. increase of genetic damage with duration of storage) does not occur in human cells in culture, or (2) the effect is masked by cell selection and/or repair processes. To inquire whether the absence of a storage effect might have been, at least in part, due to the interaction of repair processes and the effect sought, xeroderma pigmentosum cells in stationary phase were treated with N-acetoxy-AAF. This experiment likewise provided no evidence for a storage effect.