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Updated: Jul 11, 2026

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Isolation of Fidelity Variants of RNA Viruses and Characterization of Virus Mutation Frequency
Published on: June 16, 2011
Mutation rates among RNA viruses
1Laboratory of Molecular Genetics, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709-2233, USA. drake@niehs.nih.gov
Summary
The spontaneous mutation rate in riboviruses is approximately 0.76 per genome per replication. This high mutation rate, coupled with dense genomes, means even small increases can lead to population extinction.
Area of Science:
- Virology
- Evolutionary Biology
- Population Genetics
Background:
- Spontaneous mutation rate is crucial for population genetics and evolutionary modeling.
- Assessing genetic health requires understanding mutation load and rate impacts.
- Previous RNA virus mutation rate studies lacked sufficient data and theoretical frameworks.
Purpose of the Study:
- To establish a simple relationship between ribovirus mutation frequencies and mutation rates.
- To estimate the mutation rate per genome per replication for riboviruses.
- To evaluate the consequences of mutation rate changes on ribovirus populations.
Main Methods:
- Developed a novel theoretical framework to link mutation frequencies and rates in riboviruses.
- Applied the framework to available experimental data on ribovirus mutation.
- Calculated the central mutation rate per genome per replication.
Main Results:
- A central mutation rate of approximately 0.76 per genome per replication was determined for riboviruses.
- The mutation rate per round of cell infection is estimated to be around 1.5.
- Ribovirus genomes are informationally dense, making them sensitive to mutation rate increases.
Conclusions:
- Riboviruses exhibit exceptionally high spontaneous mutation rates.
- Even minor increases in mutation rate can cause extinction in ribovirus populations.
- The findings highlight the fragility of ribovirus genetic integrity and population viability.
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