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07:44
Measuring Microbial Mutation Rates with the Fluctuation Assay
Published on: November 28, 2019
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An uncertainty law for microbial evolution
Kristina Crona1, Mengming Luo2, Devin Greene1
1Department of Mathematics and Statistics 4400 Massachusetts Avenue NW Washington, DC 20016-8050, United States.
Journal of Theoretical Biology
|January 12, 2020
Summary
Higher order epistasis, unexpected effects from multiple mutations, significantly alters microbial evolution prospects. This mathematical study confirms its crucial role, impacting bacterial and higher organism adaptation.
Area of Science:
- Evolutionary Biology
- Genetics
- Mathematical Biology
Background:
- Understanding constraints and uncertainty in microbial evolution is vital for medical practice.
- Higher order epistasis, where multiple mutations have combined effects beyond individual and pairwise interactions, is increasingly observed in nature.
- The significance and interpretability of higher order epistasis have been subjects of debate.
Purpose of the Study:
- To conclusively demonstrate how higher order epistasis influences the adaptive potential of a population.
- To provide a mathematically rigorous and universally applicable framework for understanding epistasis in evolution.
Main Methods:
- Exhaustive computational search of 193,270,310 hyper-cube graphs.
- Application of graph theory principles to analyze evolutionary landscapes.
- Development of a model independent of specific fitness assumptions (e.g., additive, log-additive).
Main Results:
- Higher order epistasis demonstrably changes the adaptive trajectories and prospects of populations.
- The findings are based on comprehensive mathematical theory, offering greater precision and universality than simulation-based studies.
- The established uncertainty in microbial evolution due to higher order epistasis is robust across different baseline fitness models.
Conclusions:
- Higher order epistasis is a critical factor shaping microbial evolution and adaptation.
- Mathematical theory provides a powerful and generalizable approach to studying complex genetic interactions.
- The study resolves debates by conclusively showing the importance of higher order epistasis in evolutionary processes.
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