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Updated: May 14, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Genotypic but not phenotypic historical contingency revealed by viral experimental evolution
Stéphanie Bedhomme1, Guillaume Lafforgue, Santiago F Elena
1Instituto de Biología Molecular y Celular de Plantas, Consejo Superior de Investigaciones Científicas-UPV, 46022, València, Spain. stebed@upvnet.upv.es
BMC Evolutionary Biology
|February 21, 2013
Summary
Viral evolution is shaped by past adaptations, but this historical contingency primarily impacts genotype, not phenotype. This suggests viruses can readily adapt and re-emerge without evolutionary constraints.
Area of Science:
- Evolutionary biology
- Virology
- Genetics
Background:
- Historical contingency's role in viral evolution is underappreciated.
- Understanding past adaptations is key for viral host dynamics and escape mutant emergence.
- Sixty lineages of Tobacco etch virus (TEV) with varied histories were studied.
Purpose of the Study:
- To investigate the impact of historical contingency on viral adaptation.
- To determine if past evolutionary history constrains future adaptation.
- To analyze genotypic and phenotypic changes in TEV populations.
Main Methods:
- Experimental evolution of 60 TEV lineages over 15 host multiplication rounds.
- Adaptation assessment to both new and original hosts.
- Genotypic characterization of end-point populations.
Main Results:
- Past evolutionary history did not dictate phenotypic adaptation to a common host.
- Local adaptation signals to past hosts largely diminished.
- Genotypic footprints of past adaptations were retained, influencing new mutations and causing sequence divergence.
Conclusions:
- The impact of historical contingency in evolution depends on the trait's integration level.
- TEV genotype showed strong historical contingency, while phenotypic evolution showed weak effects.
- Viruses are not easily trapped in suboptimal phenotypes, and re-emergence is not evolutionarily constrained.
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