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Updated: Jul 14, 2026
13:48
Reverse Genetics Mediated Recovery of Infectious Murine Norovirus
Published on: June 24, 2012
Genetic heterogeneity, evolution, and recombination in noroviruses
Tung Gia Phan1, Kunio Kaneshi, Yuichi Ueda
1Department of Developmental Medical Sciences, Institute of International Health, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan.
Journal of Medical Virology
|July 4, 2007
Summary
Norovirus acute gastroenteritis affects children in Japan. This study identified multiple norovirus genotypes, including recombinant strains, and proposed a new classification system for better understanding of norovirus evolution and transmission.
Area of Science:
- Virology
- Public Health
- Genetics
Background:
- Norovirus is a leading cause of non-bacterial gastroenteritis globally.
- Understanding norovirus diversity and evolution is crucial for public health interventions.
Purpose of the Study:
- To investigate the prevalence and genetic diversity of norovirus in pediatric acute gastroenteritis cases in Japan.
- To propose a novel nomenclature for norovirus classification.
- To identify recombinant noroviruses and understand recombination patterns.
Main Methods:
- Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect norovirus in 603 fecal specimens.
- Norovirus genotypes were identified and analyzed.
- Phylogenetic analysis was performed using amino acid motifs of the capsid gene.
Main Results:
- Norovirus was detected in 8.5% of pediatric gastroenteritis cases.
- Genotypes GII/3 and GII/4 were predominant, with GIIb emerging as a leading strain.
- Eight novel recombinant noroviruses were identified, including intergenogroup and intersubgenotype recombinations.
- A new norovirus nomenclature classifying strains into seven genogroups was proposed.
Conclusions:
- This study provides insights into the genetic diversity and evolution of noroviruses in Japan.
- The identification of novel recombinant strains and recombination types highlights potential zoonotic transmission routes.
- The proposed nomenclature offers a standardized framework for global norovirus classification.
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