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Published on: June 26, 2020
Genetic variability and molecular evolution of hepatitis A virus
Juan Cristina1, Mauro Costa-Mattioli
1Laboratorio de Virología Molecular, Centro de Investigaciones Nucleares, Facultad de Ciencias, Iguá 4225, 11400 Montevideo, Uruguay. cristina@cin.edu.uy
Virus Research
|March 3, 2007
Summary
Hepatitis A virus (HAV) exhibits unique genetic variation mechanisms, including quasispecies evolution and recombination. Its lower mutation rate may explain the existence of only one serotype.
Area of Science:
- Virology
- Molecular Biology
- Genetics
Background:
- Hepatitis A virus (HAV) causes type A viral hepatitis.
- HAV belongs to the Picornaviridae family.
- HAV was first identified approximately 30 years ago.
Purpose of the Study:
- To investigate the unique characteristics of HAV within the Picornaviridae family.
- To explore HAV's mechanisms of polyprotein processing and virion morphogenesis.
- To understand HAV's genetic variation and evolution.
Main Methods:
- Analysis of HAV genetic variation.
- Study of mutation and recombination rates.
- Comparison with other Picornaviridae members.
Main Results:
- HAV circulates as quasispecies, a collection of closely related genetic variants.
- HAV utilizes mutation and recombination for survival.
- HAV exhibits a significantly lower mutation rate compared to other Picornaviridae.
- Six genetic groups (three human, three simian) and one serotype have been identified.
Conclusions:
- HAV possesses unique genetic variation mechanisms.
- The observed mode of evolution, including a lower mutation rate, likely contributes to the limited serotype diversity of HAV.
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