Migration-selection balance at multiple loci and selection on dominance and recombination

TL;DR

This paper models how migration, selection, dominance, and recombination interact at multiple loci to influence genetic load and population structure, providing explicit analytical insights under certain conditions.

Contribution

It introduces a deterministic branching process approach to approximate multilocus migration-selection balance considering dominance and recombination.

Findings

The model closely matches simulated results under low migration and recombination rates.

It provides explicit formulas for population structure based on immigrant lineage dynamics.

The approach simplifies understanding of multilocus genetic load in migration-selection scenarios.

Abstract

A steady influx of a single deleterious multilocus genotype will impose genetic load on the resident population and leave multiple descendants carrying various numbers of the foreign alleles. Provided that the foreign types are rare at equilibrium, and that all immigrant genes will eventually be eliminated by selection, the population structure can be inferred explicitly from the deterministic branching process taking place within a single immigrant lineage. Unless the migration and recombination rates were high, this simple method was a very close approximation to the simulated migration-selection balance with all possible multilocus genotypes considered.