DETECTION OF DNA-DAMAGE BY THE ALKALINE COMET ASSAY AFTER EXPOSURE TOLOW-DOSE GAMMA-RADIATION

The alkaline comet assay as described by Olive et al. (Exp. Cell Res. 198, 259-267, 1992) was used to detect DNA damage in cells exposed to low doses (0-5 cGy) of gamma radiation. Experiments were performed usi ng lymphocytes isolated from whole blood of rats. The comet parameters , normalized comet moment and comet length, described by Rent et al. ( Int. J. Radiat. Biol. 67, 655-660, 1995), were used as measurements of DNA damage. It was observed that the alkaline comet assay can detect DNA damage at doses as low as 0.6 cGy. The results of the experiments using low-dose gamma radiation are comparable with published results o btained using the alkaline comet assay according to the method of Sing h et al. (Int. J. Radiat. Biol. 66, 23-28, 1994). Based on this observ ation and analysis of results published previously, we conclude that t he version of the alkaline comet assay described by Olive et al. is as sensitive as other modifications of the comet assay reported in liter ature for the detection of DNA damage in cells exposed to low doses of ionizing radiation. (C) 1998 by Radiation Research Society.