Stability of Underdominant Genetic Polymorphisms in Population Networks

TL;DR

This paper investigates how the structure of interconnected population networks influences the stability of underdominant genetic polymorphisms, revealing that network topology can significantly affect genetic divergence despite migration.

Contribution

It extends the understanding of underdominance by analyzing its dynamics across complex population networks rather than single populations.

Findings

Network topology impacts genetic stability in population systems.

Certain network structures can enhance or reduce divergence stability.

Topology effects are sometimes non-intuitive.

Abstract

Heterozygote disadvantage is potentially a potent driver of population genetic divergence. Also referred to as underdominance, this phenomena describes a situation where a genetic heterozygote has a lower overall fitness than either homozygote. Attention so far has mostly been given to underdominance within a single population and the maintenance of genetic differences between two populations exchanging migrants. Here we explore the dynamics of an underdominant system in a network of multiple discrete, yet interconnected, populations. Stability of genetic differences in response to increases in migration in various topological networks is assessed. The network topology can have a dominant and occasionally non-intuitive influence on the genetic stability of the system.