engleski

SENSITIVITY AND DNA REPAIR CAPACITY IN ANESTHESIOLOGISTS BY THE ALKALINE COMET ASSAY, IN VITRO CHALLENGING ASSAY AND DNA REPAIR GENOTYPING

The aim of the study was to investigate the initial DNA damage induced after 2 Gy and 4 Gy of 60Co ex vivo gamma radiation, the influence of repair capability according also to the polymorphisms in DNA base excision repair hOGG1 and double strand-break repair XRCC3, and to check whether folic acid level in urine, or smoking can influence on the level of DNA damage and repair in human peripheral blood lymphocytes of 30 healthy subjects (16 F, 14 M) and 30 medical workers exposed to anaesthetics (24 F, 6 M). There was no significant difference in the mean levels of tail DNA between control and exposed samples irradiated with the same dose. Long term exposure showed correlation with the amount of DNA damage, but did not change DNA damage response immediately after irradiation. The effect of smoking was not observed in the control group. The only difference was seen for the level of residual DNA damage after 30 minutes from exposure to 4 Gy. hOGG1 polymorphic groups (control and exposed) had lower level of residual DNA damage after 2 Gy, with constant levels of residual DNA damage in homozygous wild type exposed group, although the time period for repairing the damage was different. As for 4 Gy, polymorphic groups repaired DNA damage slower than homozygous. Homozygous were repairing faster DNA, the fastest were exposed homozygous and then control ones. XRCC3 control homozygous wild type had significantly higher percentage of tail DNA from exposed ones 30 and 120 minutes after 2 Gy, while similar was found for 15 and 120 minutes after received 4 Gy dose. Two Gy residual DNA damage was equal for all groups, except for exposed homozyogous that after initial lower DNA damage remained with higher level of unrepaired DNA damage (80 % after 60 minutes, 70 % after 120 minutes). After 4 Gy, polymorphic groups had higher levels of unrepaired DNA.

SNP polymorphism ; ionising radiation ; anaesthetics ; medical workers ; comet assay ; DNA repair

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