Chalmers Conferences, 9th European Conference on Mathematical and Theoretical Biology

How can genetic interactions evolve in response to migration load?
Stephen Proulx

Last modified: 2014-06-09


Gene ßow between populations that experience different selective regimes can reduce fitness in both populations. This is particularly true for populations that experience immigration from a large, distinct source population, such as populations on the edge of a species range. How can this deleterious effect of gene flow be mitigated? We focus on the evolution of modifier loci that can affect the dominance, epistasis, or recombination rates. We first model the set of immigrant haplotypes using a branching process approach and then model the invasion of a modifier allele that may become linked to these immigrant haplotypes. We find that modifiers of the dominance coefficient and modifiers of epistasis among immigrant alleles have similar rates of spread. In principle, a modifier that reduces recombination can spread, but we find that this form of selection is much weaker than selection on epistasis or dominance. By comparing the strength of selection of this set of modifiers in a single model we are able to draw general conclusions about the evolution of genetic architecture in response to migration/selection balance.