Developmental stability covaries with genome-wide and single-locus heterozygosity in house sparrows.

Carl Vangestel,Luc Lens,Deborah A Dawson,Joachim Mergeay,Viki Vandomme,William J Etges

doi:10.1371/journal.pone.0021569

Carl Vangestel, Luc Lens + Show 4 more

Open Access

https://doi.org/10.1371/journal.pone.0021569

Copy DOI

Abstract

Fluctuating asymmetry (FA), a measure of developmental instability, has been hypothesized to increase with genetic stress. Despite numerous studies providing empirical evidence for associations between FA and genome-wide properties such as multi-locus heterozygosity, support for single-locus effects remains scant. Here we test if, and to what extent, FA co-varies with single- and multilocus markers of genetic diversity in house sparrow (Passer domesticus) populations along an urban gradient. In line with theoretical expectations, FA was inversely correlated with genetic diversity estimated at genome level. However, this relationship was largely driven by variation at a single key locus. Contrary to our expectations, relationships between FA and genetic diversity were not stronger in individuals from urban populations that experience higher nutritional stress. We conclude that loss of genetic diversity adversely affects developmental stability in P. domesticus, and more generally, that the molecular basis of developmental stability may involve complex interactions between local and genome-wide effects. Further study on the relative effects of single-locus and genome-wide effects on the developmental stability of populations with different genetic properties is therefore needed.

Highlights

Developmental stability refers to the ability of an organism to achieve a phenotypic endpoint, predetermined by its genotype and the environment, along a developmental pathway in the face of random perturbations [1]
Estimates of genetic diversity and developmental stability, averaged across individuals, significantly co-varied in the direction expected by developmental theory, whereas individual estimates were only weakly associated
Both genome-wide and locus-specific estimates of genetic diversity strongly correlated with developmental stability at the population level, and this correlation was mainly driven by genetic variation at two key loci only

Summary

Introduction

Developmental stability refers to the ability of an organism to achieve a phenotypic endpoint, predetermined by its genotype and the environment, along a developmental pathway in the face of random perturbations [1]. Because developmental stability has been shown to decrease with environmental and genetic stress and to correlate with fitness traits such as fecundity, attractiveness, competitive ability, parasite resistance and survival (see reviews in for example [1,2,3]), it has received much attention in ecology and conservation biology. The fact that relationships between FA and heterozygosity were only significant under suboptimal rearing conditions in the freshwater fish Gambusia holbrooki [12], suboptimal foraging conditions in the forest bird Turdus helleri [13], and suboptimal growing conditions in the flowering plant Lychnis viscaria [14], suggests that developmental stability may be traded-off against other vital life-history traits when individuals become energetically challenged [12,13,15]

Methods

Results

Conclusion