Effects of hepatitis B virus mutations on its replication and liver disease severity

Abdulrahim Hakami1, Abdelwahid Ali, Ahmed Hakami

  • 1Department of Medical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha 61481, Saudi Arabia.

The Open Virology Journal
|February 13, 2013
PubMed

Insights

Hepatitis B virus (HBV) mutations significantly impact chronic infection, disease severity, and viral replication. Specific mutations like basal core promoter alterations increase hepatocellular carcinoma risk, especially with genotype C.

Area of Science:

  • Hepatology and Virology
  • Molecular Biology
  • Infectious Diseases

Background:

  • Hepatitis B virus (HBV) is a major global pathogen, with approximately 400 million chronically infected individuals.
  • Infection acquired at birth or early childhood leads to over 90% chronic infection rates, contrasting with adult infections (around 5%).
  • Eight HBV genotypes and numerous subgenotypes exist, differentiated by nucleotide sequence variations.

Purpose of the Study:

  • To review the association between various HBV mutations and liver disease severity, progression, and viral replication.
  • To highlight the role of specific mutations, such as precore and basal core promoter mutations, in disease pathogenesis.
  • To discuss the predictive value of certain genotypes and mutations for hepatocellular carcinoma risk.

Main Methods:

  • Review of existing literature on HBV genotypes, mutations, and their clinical and virological implications.
  • Analysis of phenotypic assays and molecular techniques used to assess HBV replication efficiency.
  • Correlation of specific HBV mutations (e.g., G1896A, T1762/A1764) with HBeAg expression and viral persistence.

Main Results:

  • HBV genotypes and mutations are pivotal in liver disease aggravation and virus replication.
  • Precore mutations (G1896A) and basal core promoter double mutations (T1762/A1764) affect hepatitis B e antigen (HBeAg) expression, crucial for viral persistence.
  • Genotype C and basal core promoter double mutation are predictive of high hepatocellular carcinoma risk.

Conclusions:

  • HBV mutations significantly influence disease progression, severity, and replication efficiency.
  • Understanding these mutations is critical for predicting patient outcomes and managing chronic HBV infection.
  • Targeting specific mutations or genotypes may offer future therapeutic strategies.

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