The maintenance of genetic polymorphism underlying
sexually antagonistic traits
sexually antagonistic traits
File(s)
Published version
Author(s)
Flintham, Ewan
Savolainen, Vincent
Otto, Sarah
Reuter, Max
Mullon, Charles
Type
Journal Article
Abstract
Selection often favours different trait values in males and females, leading to genetic conflicts between the sexes when traits have a shared genetic basis. Such sexual antagonism has been
proposed to maintain genetic polymorphism. However, this notion is based on insights from population genetic models of single loci with fixed fitness effects. It is thus unclear how readily polymorphism emerges from sex-specific selection acting on continuous traits, where fitness effects arise
from the genotype-phenotype map and the fitness landscape. Here we model the evolution of a continuous trait that has a shared genetic basis but different optima in males and females, considering a wide variety of genetic architectures and fitness landscapes. For autosomal loci, the long-term
maintenance of polymorphism requires strong conflict between males and females that generates
uncharacteristic sex-specific fitness patterns. Instead, more plausible sex-specific fitness landscapes
typically generate stabilising selection leading to an evolutionarily stable state that consists of a single
homozygous genotype. Except for sites tightly linked to the sex determining region, our results indicate that genetic variation due to sexual antagonism should arise only rarely and often be transient,
making these signatures challenging to detect in genomic data.
proposed to maintain genetic polymorphism. However, this notion is based on insights from population genetic models of single loci with fixed fitness effects. It is thus unclear how readily polymorphism emerges from sex-specific selection acting on continuous traits, where fitness effects arise
from the genotype-phenotype map and the fitness landscape. Here we model the evolution of a continuous trait that has a shared genetic basis but different optima in males and females, considering a wide variety of genetic architectures and fitness landscapes. For autosomal loci, the long-term
maintenance of polymorphism requires strong conflict between males and females that generates
uncharacteristic sex-specific fitness patterns. Instead, more plausible sex-specific fitness landscapes
typically generate stabilising selection leading to an evolutionarily stable state that consists of a single
homozygous genotype. Except for sites tightly linked to the sex determining region, our results indicate that genetic variation due to sexual antagonism should arise only rarely and often be transient,
making these signatures challenging to detect in genomic data.
Date Issued
2025-04-01
Date Acceptance
2024-10-22
Citation
Evolution Letters, 2025, 9 (2), pp.259-272
ISSN
2056-3744
Publisher
Oxford University Press
Start Page
259
End Page
272
Journal / Book Title
Evolution Letters
Volume
9
Issue
2
Copyright Statement
© The Author(s) 2024. Published by Oxford University Press on behalf of The Society for the Study of Evolution (SSE) and European Society for Evolutionary Biology (ESEN). This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited.
License URL
Identifier
10.1093/evlett/qrae059
Subjects
polymorphism
genetic variation
balancing selection
sexual conflict
negative frequency dependence
sexual dimorphism
Publication Status
Published
Date Publish Online
2024-12-18