Long Distance Linkage Disequilibrium and Limited Hybridization Suggest Cryptic Speciation in Atlantic Cod
Hybrid zones provide unprecedented opportunity for the study of the evolution of reproductive isolation, and the extent of hybridization across individuals and genomes can illuminate the degree of isolation. We examine patterns of interchromosomal linkage disequilibrium (ILD) and the presence of hyb...
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ftpubmed:oai:pubmedcentral.nih.gov:4178228 2023-05-15T15:27:04+02:00 Long Distance Linkage Disequilibrium and Limited Hybridization Suggest Cryptic Speciation in Atlantic Cod Bradbury, Ian R. Bowman, Sharen Borza, Tudor Snelgrove, Paul V. R. Hutchings, Jeffrey A. Berg, Paul R. Rodríguez-Ezpeleta, Naiara Lighten, Jackie Ruzzante, Daniel E. Taggart, Christopher Bentzen, Paul 2014-09-26 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4178228 http://www.ncbi.nlm.nih.gov/pubmed/25259573 https://doi.org/10.1371/journal.pone.0106380 en eng Public Library of Science http://www.ncbi.nlm.nih.gov/pmc/articles/PMC http://www.ncbi.nlm.nih.gov/pubmed/25259573 http://dx.doi.org/10.1371/journal.pone.0106380 This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. CC-BY Research Article Text 2014 ftpubmed https://doi.org/10.1371/journal.pone.0106380 2014-10-05T02:04:56Z Hybrid zones provide unprecedented opportunity for the study of the evolution of reproductive isolation, and the extent of hybridization across individuals and genomes can illuminate the degree of isolation. We examine patterns of interchromosomal linkage disequilibrium (ILD) and the presence of hybridization in Atlantic cod, Gadus morhua, in previously identified hybrid zones in the North Atlantic. Here, previously identified clinal loci were mapped to the cod genome with most (∼70%) occurring in or associated with (<5 kb) coding regions representing a diverse array of possible functions and pathways. Despite the observation that clinal loci were distributed across three linkage groups, elevated ILD was observed among all groups of clinal loci and strongest in comparisons involving a region of low recombination along linkage group 7. Evidence of ILD supports a hypothesis of divergence hitchhiking transitioning to genome hitchhiking consistent with reproductive isolation. This hypothesis is supported by Bayesian characterization of hybrid classes present and we find evidence of common F1 hybrids in several regions consistent with frequent interbreeding, yet little evidence of F2 or backcrossed individuals. This work suggests that significant barriers to hybridization and introgression exist among these co-occurring groups of cod either through strong selection against hybrid individuals, or genetic incompatibility and intrinsic barriers to hybridization. In either case, the presence of strong clinal trends, and little gene flow despite extensive hybridization supports a hypothesis of reproductive isolation and cryptic speciation in Atlantic cod. Further work is required to test the degree and nature of reproductive isolation in this species. Text atlantic cod Gadus morhua North Atlantic PubMed Central (PMC) PLoS ONE 9 9 e106380 |
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Research Article Bradbury, Ian R. Bowman, Sharen Borza, Tudor Snelgrove, Paul V. R. Hutchings, Jeffrey A. Berg, Paul R. Rodríguez-Ezpeleta, Naiara Lighten, Jackie Ruzzante, Daniel E. Taggart, Christopher Bentzen, Paul Long Distance Linkage Disequilibrium and Limited Hybridization Suggest Cryptic Speciation in Atlantic Cod |
topic_facet |
Research Article |
description |
Hybrid zones provide unprecedented opportunity for the study of the evolution of reproductive isolation, and the extent of hybridization across individuals and genomes can illuminate the degree of isolation. We examine patterns of interchromosomal linkage disequilibrium (ILD) and the presence of hybridization in Atlantic cod, Gadus morhua, in previously identified hybrid zones in the North Atlantic. Here, previously identified clinal loci were mapped to the cod genome with most (∼70%) occurring in or associated with (<5 kb) coding regions representing a diverse array of possible functions and pathways. Despite the observation that clinal loci were distributed across three linkage groups, elevated ILD was observed among all groups of clinal loci and strongest in comparisons involving a region of low recombination along linkage group 7. Evidence of ILD supports a hypothesis of divergence hitchhiking transitioning to genome hitchhiking consistent with reproductive isolation. This hypothesis is supported by Bayesian characterization of hybrid classes present and we find evidence of common F1 hybrids in several regions consistent with frequent interbreeding, yet little evidence of F2 or backcrossed individuals. This work suggests that significant barriers to hybridization and introgression exist among these co-occurring groups of cod either through strong selection against hybrid individuals, or genetic incompatibility and intrinsic barriers to hybridization. In either case, the presence of strong clinal trends, and little gene flow despite extensive hybridization supports a hypothesis of reproductive isolation and cryptic speciation in Atlantic cod. Further work is required to test the degree and nature of reproductive isolation in this species. |
format |
Text |
author |
Bradbury, Ian R. Bowman, Sharen Borza, Tudor Snelgrove, Paul V. R. Hutchings, Jeffrey A. Berg, Paul R. Rodríguez-Ezpeleta, Naiara Lighten, Jackie Ruzzante, Daniel E. Taggart, Christopher Bentzen, Paul |
author_facet |
Bradbury, Ian R. Bowman, Sharen Borza, Tudor Snelgrove, Paul V. R. Hutchings, Jeffrey A. Berg, Paul R. Rodríguez-Ezpeleta, Naiara Lighten, Jackie Ruzzante, Daniel E. Taggart, Christopher Bentzen, Paul |
author_sort |
Bradbury, Ian R. |
title |
Long Distance Linkage Disequilibrium and Limited Hybridization Suggest Cryptic Speciation in Atlantic Cod |
title_short |
Long Distance Linkage Disequilibrium and Limited Hybridization Suggest Cryptic Speciation in Atlantic Cod |
title_full |
Long Distance Linkage Disequilibrium and Limited Hybridization Suggest Cryptic Speciation in Atlantic Cod |
title_fullStr |
Long Distance Linkage Disequilibrium and Limited Hybridization Suggest Cryptic Speciation in Atlantic Cod |
title_full_unstemmed |
Long Distance Linkage Disequilibrium and Limited Hybridization Suggest Cryptic Speciation in Atlantic Cod |
title_sort |
long distance linkage disequilibrium and limited hybridization suggest cryptic speciation in atlantic cod |
publisher |
Public Library of Science |
publishDate |
2014 |
url |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4178228 http://www.ncbi.nlm.nih.gov/pubmed/25259573 https://doi.org/10.1371/journal.pone.0106380 |
genre |
atlantic cod Gadus morhua North Atlantic |
genre_facet |
atlantic cod Gadus morhua North Atlantic |
op_relation |
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC http://www.ncbi.nlm.nih.gov/pubmed/25259573 http://dx.doi.org/10.1371/journal.pone.0106380 |
op_rights |
This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) , which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1371/journal.pone.0106380 |
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PLoS ONE |
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9 |
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9 |
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e106380 |
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