Detection of XRCC1 Expression and (8-OHdG) Levels as a marker of Oxidative DNA Damage in Individuals Exposed to Low Dose of Gamma Rays

To study ionizing radiation (IR) effects on biological systems there several techniques are used to identify molecular features of IR exposure, urinary detection of 8-ohdG by ELISA as a marker of DNA oxidative stress is one of the techniques was used in this research, when IR absorbs in a cell so that causing DNA damage and releases 8-ohdG through correction damage. The detection of XRCC1 expression by QRT- PCR is else technique in this study. The genotoxic of IR can be observed even at a low doses 5cGy, According to RPC (Radiation Protection Center) limited place in Baghdad as a source of low-dose IR( Europium 152) before it is removed, some of workers and slums are exposed to low dose of γ-rays ( 5cGy to 10 cGy ). The study groups included the (G1)fifty workers in metal melting are working closely with ( IR source), (G2)twenty five individuals from slums near the IR source, and(G3) twenty five volunteers individuals of male in different age, didn't exposure to diagnostic x-ray examination or other radiotherapy. Peripheral blood are collected and urine from all individuals. The results indicate that the level of 8-OHDG factor in workers higher than slums individuals and negatively related with XRCC1 expression, also the expression of XRCC1 decreased in individuals exposed for more than 5cGy, and increasing in slums exposed to 5cGy. The low dose of γ-rays causing genotoxic effects due to a combination of DNA-damaging effects and reduced capacity of DNA repair.