Abstract: Purpose and Methods : Single cell gel elect rophoresis ( SCGE) , sister chromatid exchanges ( SCE) ,chromosome aberrations are three methods to determine DNA damage and repair. The purpose of this study was to compare the sensitivity and accuracy of the three methods. Results : SCGE was the most sensitive one for detecting DNA damage induced by H2O2 . The rates of DNA damage at 100μmol/ L and 200μmol/ L of H2O2 were 45. 6 % and 59. 5 % measured by SCGE , and 3. 4 % and 5. 3 % by SCE , respectively. DNA damage induced by H2O2 was not detectable with chromosome aberration method. Conclusion : SCGE , SCE and chromosome aberration were considered to be used in three different levels , whereas SCGE was a quick , simple and more sensitive technique for detecting DNA damage and repair.

Key words: SCGE, SCE, chromosome aberration, DNA damage, DNA repair