A study of the relationship between the effects of tenofovir on the frequency of micronucleus and the polymorphisms in APE1, XRCC1 AND XPD dna repair genes

The tenofovir is a drug on the order of a nucleotide revers transcriptase inhibitor in viral infections such as HBV and HIV. This study were carried out the following groups healty volunteers (15), untreated chronic hepatitis B patients (10), the hepatitis B patients who have been treated for 0-6 months and the hepatitis B patients who have been treated for 12+ months. In this study, mitotic index (MI) and micronucleus (MN) tests were used in every volunteers to determine the possible genotoxic effects of the tenofovir and the relationship with the gene polymorphisms from DNA repair such APE1 Asp148Glu, XRCC1 Arg194Trp, XRCC1 Arg399Gln and XPD Lys751Gln were examined. It has been determined that the tenofovir doesn't have a significant effect on MI and frequency of MN. But it has been observed that MI and MN values in the HBV patient groups were higher than those of healthy group. However there was not any significant relationship between the frequency of MN and genetic polymorphisms such as APE1 Asp148Glu, XRCC1 Arg194Trp, XRCC1 Arg399Gln and XPD Lys751Gln. To the best of knowledge, there is not any study on regarding the genotoxicity due to the tenofovir treatment in HBV patients in the literature. In the final analysis, we suggest that chronic tenofovir administration does not have any genotoxic effect on routin doses. On the other hand, HBV has higher genotoxicity potential itself. Key Words: Tenofovir, mitotic index (MI), micronucleus (MN), gene polymorpisms, genotoxicity, HBV.