Hepatitis B virus (HBV) pregenomic RNA contains a hairpin structure (ε) located in the preCore region, essential for viral replication. ε stability is enhanced by the presence of preCore variants and ε is recognized by the HBV polymerase (Pol). Mutations in the retrotranscriptase domain (YMDD) of Pol are associated with treatment resistance. The aim of this study was to analyze the preCore regi...

The capacities to induce the synthesis of hepatitis B virus (HBV) unit-length DNA were compared for two HBV DNAs with an overall sequence diversity of about 10%. They had been cloned from serum (DNA2) and from a hepatocellular carcinoma (DNA4), respectively. As a major difference, DNA4 carries a translational stop signal preventing the synthesis of precore protein. Progeny DNA yields obtained a...

Variants in the precore (G(1896)A) and core promoter (A(1762)T, G(1764)A) regions of hepatitis B virus (HBV) may be related to serum HBV DNA levels and severity of liver disease. The aims of this nationwide study were to determine the prevalence of HBV precore/core promoter variants in the United States and the association between these variants and patient demographics, HBV genotypes, serum HB...

Background:Tenofovir is among the first-line treatments for chronic hepatitis B (CHB) virus infection. We evaluated the efficacy of Tenofovir in the treatment of Iranian adult patients with CHB. Methods: In a retrospective study, we evaluated 154 HBsAg positive patients referred to Sadoughi hospital in Yazd-Iran for treatment ...

The biosynthesis of the secretory core gene product of the duck hepatitis B virus (DHBe protein) was examined. Recombinant vaccinia viruses were constructed encoding either the full-length or C-terminally truncated forms of the DHBe precursor protein (precore protein) and used to express these proteins in the human hepatoma cell line HepG2. Western immunoblot analysis of core gene products isol...

AIM To evaluate HBV quasispecies (QA) complexity in the preCore/Core regions in relation to HBeAg status, and explore QA changes under natural evolution and nucleoside analogue (NUC) treatment. METHODS Ultra-deep pyrosequencing of HBV preCore/Core regions in 30 sequential samples (baseline [diagnosis], treatment-free, and treatment-nonresponse) from 10 retrospectively selected patients groupe...

BACKGROUND Long-term lamivudine therapy, despite its initial effectiveness against hepatitis B virus (HBV), is associated with the emergence of drug resistance mutations in polymerase protein. OBJECTIVES The aim of the present study was to determine the prevalence of precore and lamivudine drug resistance mutations in lamivudine treated patients with chronic B hepatitis. PATIENTS AND METHOD...

A double mutation which converts nucleotide 1765 from A to T and nucleotide 1767 from G to A is frequently found in the hepatitis B virus (HBV) genome isolated from HBV patients with chronic hepatitis symptoms. This double mutation is located in the core promoter that controls the transcription of the precore RNA and the core RNA. In addition, this double mutation also resides in the X protein ...

Chronic carriers of hepatitis B infection often harbour virus strains with mutations in the precore region. These mutations are temporally associated with the development of HBeAg loss and seroconversion to anti-HBe. The most common precore mutation is a stop codon at position 1896, but other mutations leading to abolished HBeAg secretion have been described. Here, a novel precore mutation intr...

OBJECTIVES Hepatitis B virus (HBV) with a stop mutation at precore codon 28 (TGG-->TAG, tryptophan-->stop) was investigated to clarify if such a mutant virus might play a role in hepatocarcinogenesis. METHODS A total of 73 patients with HBV-related hepatocellular carcinoma were included in this study. Polymerase chain reaction (PCR) was performed in DNA samples extracted from 73 sera to ampli...