Mutations and methods of analysis of mutations in Hepatitis B virus

Manoj Kumar Rajput; Manoj Kumar Rajput

doi:10.3934/microbiol.2020024

AIMS Microbiology

2020, Volume 6, Issue 4: 401-421. doi: 10.3934/microbiol.2020024

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Review

Mutations and methods of analysis of mutations in Hepatitis B virus

Manoj Kumar Rajput ^,

National Institute of Biologicals, India

Received: 29 July 2020 Accepted: 23 October 2020 Published: 27 October 2020

Immunization programmes against hepatitis-B are being carried out since more than three decades but still HBV is a major public health problem. Hepatitis B virus (HBV) genome consists of circular and partial double stranded DNA. Due to partial double stranded DNA, it uses an RNA intermediate during replication. This replicative strategy of HBV and lack of polymerase proofreading activity give rise to error occurrences comparable to retroviruses. The low fidelity of polymerase, overlapping reading frames and high replication rate produces many non-identical variants at every cycle of replication. Therefore, HBV spreads with mutations and variations. The mutations have been reported both in non-structural as well as structural genes of HBV genome. Recent advances in molecular biology have made easier to analyse these mutations. Hepatitis B antiviral therapy and immunization are all influenced by genetic variability. The analysis and understanding of these mutations are important for therapy against hepatitis B and updating of diagnostic tools. The present review discusses about mutations occurring in whole HBV genome. The mutation occurring both in structural and non-structural genes and non-coding regions have been described in details. It is much more informative because most of literature available, covers only individual gene or DNA regions of HBV.
- Hepatitis B virus,
- HBV variants,
- liver disease,
- mutation
Citation: Manoj Kumar Rajput. Mutations and methods of analysis of mutations in Hepatitis B virus[J]. AIMS Microbiology, 2020, 6(4): 401-421. doi: 10.3934/microbiol.2020024

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Abstract

Immunization programmes against hepatitis-B are being carried out since more than three decades but still HBV is a major public health problem. Hepatitis B virus (HBV) genome consists of circular and partial double stranded DNA. Due to partial double stranded DNA, it uses an RNA intermediate during replication. This replicative strategy of HBV and lack of polymerase proofreading activity give rise to error occurrences comparable to retroviruses. The low fidelity of polymerase, overlapping reading frames and high replication rate produces many non-identical variants at every cycle of replication. Therefore, HBV spreads with mutations and variations. The mutations have been reported both in non-structural as well as structural genes of HBV genome. Recent advances in molecular biology have made easier to analyse these mutations. Hepatitis B antiviral therapy and immunization are all influenced by genetic variability. The analysis and understanding of these mutations are important for therapy against hepatitis B and updating of diagnostic tools. The present review discusses about mutations occurring in whole HBV genome. The mutation occurring both in structural and non-structural genes and non-coding regions have been described in details. It is much more informative because most of literature available, covers only individual gene or DNA regions of HBV.

Conflicts of interest

The author declares no conflicts of interest in this paper.

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