Effects of temperature on sister chromatid exchanges.

The influence of temperature on sister chromatid exchanges was investigated, and the results are discussed in connection with factors possible involved in temperature-induced SCE-formation. Whereas the SCE frequency increased with increasing growth temperature in a cell line of Xenopus laevis (EAX), which permits the examination of great temperature differences, a Chinese hamster cell line (V-79) revealed a U-shaped temperature-response curve. In addition, it was found that cold treatment at 4 degrees C caused an induction of SCEs in the V-79 cell line. Different BrdU concentrations had no effect on the temperature-induced SCE frequencies and mitomycin C led to an induction of SCEs parallel to the base-line values at different temperatures.