Genotypic distribution at the limits to natural and artificial selection with mutation

Area of Science:

• Population Genetics
• Quantitative Genetics
• Evolutionary Biology

Background:

• Understanding genotypic distribution changes under selection is crucial for evolutionary studies.
• Previous models often simplify complex selection dynamics.

Purpose of the Study:

• To describe a general procedure for analyzing genotypic distribution changes under stabilizing and truncation selection.
• To investigate genotypic distributions at the limits of selection.
• To compare these with a Gaussian approximation.

Main Methods:

• Developed a general procedure for analyzing genotypic distributions under selection.
• Employed a Gaussian approximation for comparison.
• Investigated the impact of gene frequency and number of loci on distribution accuracy.

Main Results:

• Truncation selection primarily causes gene frequency changes, not linkage disequilibrium, in the long term.
• The Gaussian approximation is accurate for additive gene effects when gene frequencies are not extreme (0.05-0.95) and loci number is sufficient (>50).
• Genotypic distributions at selection limits depend on whether natural selection or mutation is the primary driver of variation.

Conclusions:

• The developed procedure provides a robust method for analyzing genotypic distributions under selection.
• Mutation plays a significant role in maintaining genetic variability and influences long-term evolutionary response.
• The Gaussian approximation is a useful, though not universally perfect, tool for modeling genetic changes.