Molecular Characterization of Hepatitis B Virus Strains Isolated from Chronic Hepatitis B Patients in Southeastern Region of Turkey

Objectives: The aim of the present study was to assess the molecular aspects of HBV strains isolated from chronic hepatitis B (CHB) patients, in the Southeastern region of Turkey. Materials and Methods: The study involved a total of 110 patients, 57 of them were treatment naive. 53 were undergoing nucleos(t)ide analogue (NUC) therapy, whom were diagnosed with CHB between July 2010 and April 2011 in the Southeastern region of Turkey. We analysed the HBV pol gene by amplification and direct sequencing with using polymerase chain reaction. Results: The phylogenetic and genotype analysis showed that all (100%) of the patients were infected with HBV genotype D. The prevalence of antiviral drug-associated potential vaccine-escape mutant was 10.5% among treatment naive and 15% NUC therapy group. S gene mutation among treatment naive group and NUC therapy group were 19% and 26.4%. Conclusion: Determination of genotypes/subgenotypes of HBV may provide robust epidemiological data related to their circulation as well as their transmissibility. However, the findings of HBV pol gene mutations may be helpful in the management of rescue strategies in NUCs resistant patients in Southeastern region of Turkey.