The hepatitis B virus (HBV) X gene shares sequences with both the polymerase and precore genes, carries several regulatory signals critical to the replicative cycle, and its product has a transactivating function. In this study, the X gene sequences of 29 HBV strains from 14 different countries were characterized and compared to all corresponding databank sequences where the origin of the strai...

background: hepatitis b virus (hbv) infection is the most common cause of end-stage liver disease in iran. more than 70% of cases are negative for the hepatitis b e antigen (hbeag) and have a long-term response to antiviral therapy, as well as a high relapse rate after discontinuing lamivudine or interferon. these features could be due, in part, to genetic variation of the hbv genome. materials...

To assess the prevalence and clinical significance of hepatitis B virus (HBV) genotypes and precore and core promoter mutations in Taiwan, a cohort of 200 Taiwanese chronic hepatitis B patients was analyzed. The HBV genotypes and sequences of the precore and the core promoter regions were determined in 66 asymptomatic carriers and 134 patients who had liver biopsy-verified chronic hepatitis and...

The genetic diversity of HBV in human population is often a reflection of its genetic admixture. The aim of this study was to explore the genotypic diversity of HBV in Cuba. The S genomic region of Cuban HBV isolates was sequenced and for selected isolates the complete genome or precore-core sequence was analyzed. The most frequent genotype was A (167/250, 67%), mainly A2 (149, 60%) but also A1...

Infection with hepatitis B virus leads to a wide spectrum of liver injury, including self-limited acute hepatitis, fulminant hepatitis, and chronic hepatitis with progression to cirrhosis or acute exacerbation to liver failure, as well as an asymptomatic chronic carrier state. Several studies have suggested that the hepatitis B core antigen could be an immunological target of cytotoxic T lympho...

Hepatitis B virus (HBV), nowadays, is one of the major human pathogens worldwide. Approximately, 400 million people worldwide have chronic HBV infection. Only 5% of persons infected during adulthood develop chronic infection. The reverse is true for those infected at birth or in early childhood, i.e. more than 90% of these persons progress to chronic infection. Currently, eight different genoty...

Hepatitis B virus (HBV) DNA is prone to mutations because of the proofreading deficiencies of HBV polymerase. We have identified hepatocellular carcinoma (HCC) survival-associated HBV mutations in the X protein region of HBV DNA. In the present study, we extend our research to assess HCC survival-associated HBV mutations in the HBV precore/core (PreC/C) region. The PreC/C region was amplified a...

The global prevalence of hepatitis B virus is estimated to be 350 million chronic carriers, varying widely from low (<2%, as in Western Europe, North America, New Zealand, Australia, and Japan) to high (>8% as in Africa, Southeast Asia, and China). The overall prevalence in Brazil is about 8%. There are currently 7 genotypic variations, from A to G, and also 4 main surface antigen subtypes: adw...

Hepatitis B virus (HBV) infection is a global health issue. Effective and individualized treatment of chronic hepatitis B to prevent progression to end-stage liver diseases and hepatocellular carcinoma is needed. HBV can be classified into eight genotypes (A-H) on the basis of genome sequence divergence. In addition, several naturally occurring HBV mutants have also been identified. The epidemi...

Hepatitis B virus (HBV) is a major cause worldwide of liver disease, including hepatocellular carcinoma. There are eight known genotypes (A-H), of which genotype A has been divided into two subtypes: A2, prevalent in Europe, and A1, which is prevalent in sub-Saharan Africa, but also occurs in southern Asia. In this study, which includes 14 new complete genomes of non-European genotype A HBV, it...