Document type
Journal articles
Document subtype
Full paper
Title
Partial Selfing Can Reduce Genetic Loads While Maintaining Diversity During Experimental Evolution
Participants in the publication
Ivo M. Chelo (Author)
Dep. Biologia Animal
cE3c
Bruno Afonso (Author)
Sara Carvalho (Author)
Ioannis Theologidis (Author)
Christine Goy (Author)
Ania Pino-Querido (Author)
Stephen R. Proulx (Author)
Henrique Teotónio (Author)
Summary
Partial selfing, whereby self- and cross- fertilization occur in populations at intermediate frequencies, is generally thought to be evolutionarily unstable. Yet, it is found in natural populations. This could be explained if populations with partial selfing are able to reduce genetic loads and the possibility for inbreeding depression while keeping genetic diversity that may be important for future adaptation. To address this hypothesis, we compare the experimental evolution of Caenorhabditis elegans populations under partial selfing, exclusive selfing or predominant outcrossing, while they adapt to osmotically challenging conditions. We find that the ancestral genetic load, as measured by the risk of extinction upon inbreeding by selfing, is maintained as long as outcrossing is the main reproductive mode, but becomes reduced otherwise. Analysis of genome-wide single-nucleotide polymorphisms (SNPs) during experimental evolution and among the inbred lines that survived enforced inbreeding indicates that populations with predominant outcrossing or partial selfing maintained more genetic diversity than expected with neutrality or purifying selection. We discuss the conditions under which this could be explained by the presence of recessive deleterious alleles and/or overdominant loci. Taken together, our observations suggest that populations evolving under partial selfing can gain some of the benefits of eliminating unlinked deleterious recessive alleles and also the benefits of maintaining genetic diversity at partially dominant or overdominant loci that become associated due to variance of inbreeding levels.
Date of Submisson/Request
2019-04-03
Date of Acceptance
2019-07-17
Date of Publication
2019-07-05
Institution
FACULDADE DE CIÊNCIAS DA UNIVERSIDADE DE LISBOA
Where published
G3: Genes|Genomes|Genetics
Publication Identifiers
ISSN - 2160-1836
Publisher
Genetics Society of America
Number of pages
10
Starting page
2811
Last page
2821
Document Identifiers
DOI -
https://doi.org/10.1534/g3.119.400239
URL -
http://dx.doi.org/10.1534/g3.119.400239
Awards
Featured article
GSA Journals Spotlight 2019
Rankings
SCIMAGO Q1 (2019) - 1.731 - Genetics