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Updated: May 23, 2026
18:10
Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
[Genetic variability of type 3 echoviruses]
Wasfi Farès1, Dorra Rezig, Ahlem Ben Yahia
1Laboratoire de référence OMS pour la poliomyélite et la rougeole, Institut Pasteur, Tunis, Tunisie. fwasfi@yahoo.fr
Annales De Biologie Clinique
|April 10, 2012
Summary
Genetic analysis of type 3 echoviruses (E-3) reveals two distinct genogroups circulating globally. This study classifies E-3 strains, aiding understanding of this meningitis-associated virus.
Area of Science:
- Virology
- Molecular Epidemiology
- Genetics
Context:
- Echoviruses type 3 (E-3) are linked to serious human diseases, including meningitis and type 1 diabetes.
- Limited genetic and antigenic variability data exists for E-3, hindering molecular epidemiology.
- North African E-3 sequences are underrepresented in international literature.
Purpose:
- To assess the genetic and antigenic variability in the VP1 region of type 3 echoviruses.
- To classify E-3 strains into genogroups and genotypes based on VP1 sequences.
- To identify potential genotype-specific antigenic determinants.
Summary:
- Phylogenetic analysis of 46 VP1 sequences (9 from Tunisian infants) revealed two distinct E-3 genogroups (I and II) with up to 29.1% genetic variability.
- Genogroup I showed higher diversity, potentially containing multiple genotypes (≤15.1% divergence), while Genogroup II likely represents a single genotype (≤13.8% divergence).
- Both genogroups circulate concurrently, exhibiting wide geographical and temporal distribution, with noted amino acid substitutions potentially defining specific variants.
Impact:
- Provides the first classification of E-3 into genogroups and genotypes.
- Introduces novel E-3 sequences from North Africa, expanding geographical representation.
- Enhances understanding of the molecular epidemiology of human enteroviruses, specifically Echovirus type 3.
Related Concept Videos
01:25Genetic Variation
Genetic variation is the diversity in DNA sequences found among individuals of the same species. This diversity is crucial for a species' survival because it helps organisms adapt to environmental changes. Genetic variation begins with fertilization, where an egg and sperm cell merge. Each of these cells carries 23 chromosomes, up to 46 in the fertilized egg. Chromosomes are long DNA strands that contain genes, the basic units of heredity.
Genes exist in different versions called alleles, which...
Genes exist in different versions called alleles, which...
00:36Viral Mutations
A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material for adaptive...
00:57Viral Recombination
Cells are sometimes infected by more than one virus at once. When two viruses disassemble to expose their genomes for replication in the same cell, similar regions of their genomes can pair together and exchange sequences in a process called recombination. Alternatively, viruses with segmented genomes can swap segments in a process called reassortment.