A computer program to simulate multilocus genotype data with spatially autocorrelated allele frequencies
Gilles Guillot1, Filipe Santos
1Centre for Ecological and Evolutionary Synthesis Department of Biology, University of Oslo, PO Box 1066 Blindern, N-0316 Oslo Norway. gilles.guillot@bio.uio.no
Molecular Ecology Resources
|May 14, 2011
Summary
Isolation by distance (IBD) violates population genetic model assumptions, leading to inaccurate inferences. A new simulation program helps assess IBD
Area of Science:
- Population genetics
- Spatial genetics
- Bioinformatics
Background:
- Many population genetic models assume Hardy-Weinberg and linkage equilibrium within groups.
- This assumption is often violated by spatial structure from isolation by distance (IBD).
- IBD can lead to nonrandom mating and affect allele frequency distributions.
Purpose of the Study:
- To develop a flexible model and simulation program for data with spatial genetic structure.
- To assess how isolation by distance (IBD) impacts population genetic inference.
- To evaluate the effectiveness of different spatial sampling schemes.
Main Methods:
- Developed a computer program to simulate spatial variations in allele frequencies due to IBD and barriers.
- Used the program to assess the accuracy of cluster inference under panmixia assumptions.
- Investigated the effects of clumped versus uniform spatial sampling on inference accuracy.
Main Results:
- Isolation by distance can substantially inflate the number of inferred populations, creating spurious clusters.
- The effect of spatial sampling scheme on inference accuracy was minimal.
- Strong IBD relative to sampling domain size led to the most significant inference errors.
Conclusions:
- The developed simulation tool aids in evaluating statistical inference methods and designing spatial sampling strategies.
- IBD poses a significant challenge to accurate population genetic inference, often necessitating specialized models.
- The simulation program is integrated into the R package Geneland for broader accessibility.
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