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A coalescent dual process in a Moran model with genic selection
1Department of Statistics, University of Oxford, Oxford, UK. etheridge@stats.ox.ac.uk
Theoretical Population Biology
|April 4, 2009
Summary
We developed a coalescent dual process for population genetics models with selection. This new method aids in understanding allele dynamics and reconstructing ancestral lineages.
Area of Science:
- Population Genetics
- Mathematical Biology
- Stochastic Processes
Background:
- The Moran model and Wright-Fisher diffusion are fundamental in population genetics.
- Understanding allele dynamics under selection is crucial for evolutionary studies.
- Existing models often simplify or omit the complexities of genic selection.
Purpose of the Study:
- To derive a coalescent dual process for a multi-type Moran model incorporating genic selection.
- To expand transition functions for Moran models and Wright-Fisher diffusion limits.
- To apply the coalescent dual to the harmonic measure problem for allele loss and survival.
Main Methods:
- Utilized a generator approach to derive the coalescent dual process.
- Employed a graphical representation of the Moran model to identify the dual process.
- Extended existing dual process constructions for diffusion models with selection.
Main Results:
- Successfully derived a coalescent dual process for multi-type Moran models with genic selection.
- Established connections between the coalescent dual and existing models like the Ancestral Selection Graph.
- Provided a novel solution to the harmonic measure problem concerning allele loss and surviving alleles.
Conclusions:
- The derived coalescent dual process offers a powerful new tool for analyzing population genetic models with selection.
- This framework enhances the reconstruction of genealogical histories in the presence of selection.
- The application to the harmonic measure problem demonstrates the practical utility of the new dual process.
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