Phylogenetic Analysis of HBV Based on PreS Region Iranian Hepatocellular Carcinoma Patients

Background and aims: there are eight genotypes (a-h) of hepatitis b virus (hbv), which show a characteristicworldwide distribution. genotyping can be accomplished based on a partial sequence of hbv genome such as the presor s gene. the aim of this study was to determine the hbv genotypes in iranian hepatocellular carcinoma (hcc) patientswith chronic hbv infection.methods: serum sample of 10 hcc patients with chronic hbv infection were subjected to pres hemi-nested pcr. theviral genotype of each sample was determined by bi-directional sequencing of the pres amplicon and phylogeneticanalysis by comparing the nucleotide sequence with 33 reference hbv strains obtained from the genbank.results: phylogenetic analysis based on pres region sequences disclosed that all isolated strains belonged to genotyped. analysis of sequences revealed that all the sequences contained amino acid substitutions. in the pres2 region of twosamples, a point mutation in the start codon was found. there were some deletions with 3, 6 and 8 amino acids in pres2region of three samples.conclusions: despite the low number of samples, these data revealed that the hbv genotype d is dominant in iranianhccpatients. most of the mutations are located at immunodominant epitopes involved in borland t cell recognition.