1
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Watson KB, Lehnert SJ, Bentzen P, Kess T, Einfeldt A, Duffy S, Perriman B, Lien S, Kent M, Bradbury IR. Environmentally associated chromosomal structural variation influences fine-scale population structure of Atlantic Salmon (Salmo salar). Mol Ecol 2021; 31:1057-1075. [PMID: 34862998 DOI: 10.1111/mec.16307] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 10/25/2021] [Accepted: 11/19/2021] [Indexed: 01/17/2023]
Abstract
Chromosomal rearrangements (e.g., inversions, fusions, and translocations) have long been associated with environmental variation in wild populations. New genomic tools provide the opportunity to examine the role of these structural variants in shaping adaptive differences within and among wild populations of non-model organisms. In Atlantic Salmon (Salmo salar), variations in chromosomal rearrangements exist across the species natural range, yet the role and importance of these structural variants in maintaining adaptive differences among wild populations remains poorly understood. We genotyped Atlantic Salmon (n = 1429) from 26 populations within a highly genetically structured region of southern Newfoundland, Canada with a 220K SNP array. Multivariate analysis, across two independent years, consistently identified variation in a structural variant (translocation between chromosomes Ssa01 and Ssa23), previously associated with evidence of trans-Atlantic secondary contact, as the dominant factor influencing population structure in the region. Redundancy analysis suggested that variation in the Ssa01/Ssa23 chromosomal translocation is strongly correlated with temperature. Our analyses suggest environmentally mediated selection acting on standing genetic variation in genomic architecture introduced through secondary contact may underpin fine-scale local adaptation in Placentia Bay, Newfoundland, Canada, a large and deep embayment, highlighting the importance of chromosomal structural variation as a driver of contemporary adaptive divergence.
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Affiliation(s)
- K Beth Watson
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Northwest Atlantic Fisheries Centre, Fisheries and Oceans Canada, St. John's, Newfoundland and Labrador, Canada
| | - Sarah J Lehnert
- Northwest Atlantic Fisheries Centre, Fisheries and Oceans Canada, St. John's, Newfoundland and Labrador, Canada
| | - Paul Bentzen
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Tony Kess
- Northwest Atlantic Fisheries Centre, Fisheries and Oceans Canada, St. John's, Newfoundland and Labrador, Canada
| | - Antony Einfeldt
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Steven Duffy
- Northwest Atlantic Fisheries Centre, Fisheries and Oceans Canada, St. John's, Newfoundland and Labrador, Canada
| | - Ben Perriman
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Sigbjørn Lien
- Department of Animal and Aquacultural Sciences (IHA), Faculty of Life Sciences (BIOVIT), Centre for Integrative Genetics (CIGENE), Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Matthew Kent
- Department of Animal and Aquacultural Sciences (IHA), Faculty of Life Sciences (BIOVIT), Centre for Integrative Genetics (CIGENE), Norwegian University of Life Sciences (NMBU), Ås, Norway
| | - Ian R Bradbury
- Department of Biology, Dalhousie University, Halifax, Nova Scotia, Canada.,Northwest Atlantic Fisheries Centre, Fisheries and Oceans Canada, St. John's, Newfoundland and Labrador, Canada
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2
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Ackiss AS, Magee MR, Sass GG, Turnquist K, McIntyre PB, Larson WA. Genomic and environmental influences on resilience in a cold-water fish near the edge of its range. Evol Appl 2021; 14:2794-2814. [PMID: 34950230 PMCID: PMC8674893 DOI: 10.1111/eva.13313] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 10/05/2021] [Accepted: 10/07/2021] [Indexed: 02/06/2023] Open
Abstract
Small, isolated populations present a challenge for conservation. The dueling effects of selection and drift in a limited pool of genetic diversity make the responses of small populations to environmental perturbations erratic and difficult to predict. This is particularly true at the edge of a species range, where populations often persist at the limits of their environmental tolerances. Populations of cisco, Coregonus artedi, in inland lakes have experienced numerous extirpations along the southern edge of their range in recent decades, which are thought to result from environmental degradation and loss of cold, well-oxygenated habitat as lakes warm. Yet, cisco extirpations do not show a clear latitudinal pattern, suggesting that local environmental factors and potentially local adaptation may influence resilience. Here, we used genomic tools to investigate the nature of this pattern of resilience. We used restriction site-associated DNA capture (Rapture) sequencing to survey genomic diversity and differentiation in southern inland lake cisco populations and compared the frequency of deleterious mutations that potentially influence fitness across lakes. We also examined haplotype diversity in a region of the major histocompatibility complex involved in stress and immune system response. We correlated these metrics to spatial and environmental factors including latitude, lake size, and measures of oxythermal habitat and found significant relationships between genetic metrics and broad and local factors. High levels of genetic differentiation among populations were punctuated by a phylogeographic break and residual patterns of isolation-by-distance. Although the prevalence of deleterious mutations and inbreeding coefficients was significantly correlated with latitude, neutral and non-neutral genetic diversity were most strongly correlated with lake surface area. Notably, differences among lakes in the availability of estimated oxythermal habitat left no clear population genomic signature. Our results shed light on the complex dynamics influencing these isolated populations and provide valuable information for their conservation.
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Affiliation(s)
- Amanda S. Ackiss
- Wisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
- U.S. Geological SurveyGreat Lakes Science CenterAnn ArborMichiganUSA
| | | | - Greg G. Sass
- Escanaba Lake Research StationWisconsin Department of Natural ResourcesBoulder JunctionWisconsinUSA
| | - Keith Turnquist
- Wisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
| | - Peter B. McIntyre
- Department of Natural Resources and the EnvironmentCornell UniversityIthacaNew YorkUSA
| | - Wesley A. Larson
- U.S. Geological SurveyWisconsin Cooperative Fishery Research UnitCollege of Natural ResourcesUniversity of Wisconsin‐Stevens PointStevens PointWisconsinUSA
- National Oceanographic and Atmospheric AdministrationNational Marine Fisheries ServiceAlaska Fisheries Science CenterAuke Bay LaboratoriesJuneauAlaskaUSA
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3
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Des Roches S, Pendleton LH, Shapiro B, Palkovacs EP. Conserving intraspecific variation for nature's contributions to people. Nat Ecol Evol 2021; 5:574-582. [PMID: 33649544 DOI: 10.1038/s41559-021-01403-5] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Accepted: 01/25/2021] [Indexed: 01/31/2023]
Abstract
The rapid loss of intraspecific variation is a hidden biodiversity crisis. Intraspecific variation, which includes the genomic and phenotypic diversity found within and among populations, is threatened by local extinctions, abundance declines, and anthropogenic selection. However, biodiversity assessments often fail to highlight this loss of diversity within species. We review the literature on how intraspecific variation supports critical ecological functions and nature's contributions to people (NCP). Results show that the main categories of NCP (material, non-material, and regulating) are supported by intraspecific variation. We highlight new strategies that are needed to further explore these connections and to make explicit the value of intraspecific variation for NCP. These strategies will require collaboration with local and Indigenous groups who possess critical knowledge on the relationships between intraspecific variation and ecosystem function. New genomic methods provide a promising set of tools to uncover hidden variation. Urgent action is needed to document, conserve, and restore the intraspecific variation that supports nature and people. Thus, we propose that the maintenance and restoration of intraspecific variation should be raised to a major global conservation objective.
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Affiliation(s)
- Simone Des Roches
- Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, CA, USA.,School of Aquatic and Fisheries Sciences, University of Washington, Seattle, WA, USA
| | - Linwood H Pendleton
- Centre for the Fourth Industrial Revolution - Ocean, Lysaker, Norway.,Ifremer, CNRS, UMR 6308, AMURE, IUEM University of Western Brittany, Plouzané, France.,Global Change Institute, University of Queensland, Brisbane, Queensland, Australia.,Duke University, Durham, NC, USA
| | - Beth Shapiro
- Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, CA, USA.,Howard Hughes Medical Institute, University of California, Santa Cruz, CA, USA
| | - Eric P Palkovacs
- Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, CA, USA.
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4
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Armstrong JB, Schindler DE, Cunningham CJ, Deacy W, Walsh P. Watershed complexity increases the capacity for salmon–wildlife interactions in coastal ecosystems. Conserv Lett 2019. [DOI: 10.1111/conl.12689] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Affiliation(s)
| | - Daniel E. Schindler
- School of Aquatic and Fishery Sciences University of Washington Seattle Washington
| | - Curry J. Cunningham
- College of Fisheries and Ocean Sciences University of Alaska Fairbanks Juneau Alaska
| | - William Deacy
- Department of Fisheries and Wildlife Oregon State University Corvallis Oregon
- Arctic Network U.S. National Park Service 4175 Geist Road Fairbanks Alaska 99709 USA
| | - Patrick Walsh
- U.S. Fish and Wildlife Service Togiak National Wildlife Refuge Togiak Alaska
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5
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Armstrong C, Davies RG, González‐Quevedo C, Dunne M, Spurgin LG, Richardson DS. Adaptive landscape genetics and malaria across divergent island bird populations. Ecol Evol 2019; 9:12482-12502. [PMID: 31788192 PMCID: PMC6875583 DOI: 10.1002/ece3.5700] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2019] [Revised: 08/28/2019] [Accepted: 09/02/2019] [Indexed: 12/31/2022] Open
Abstract
Environmental conditions play a major role in shaping the spatial distributions of pathogens, which in turn can drive local adaptation and divergence in host genetic diversity. Haemosporidians, such as Plasmodium (malaria), are a strong selective force, impacting survival and fitness of hosts, with geographic distributions largely determined by habitat suitability for their insect vectors. Here, we have tested whether patterns of fine-scale local adaptation to malaria are replicated across discrete, ecologically differing island populations of Berthelot's pipits Anthus berthelotii. We sequenced TLR4, an innate immunity gene that is potentially under positive selection in Berthelot's pipits, and two SNPs previously identified as being associated with malaria infection in a genome-wide association study (GWAS) in Berthelot's pipits in the Canary Islands. We determined the environmental predictors of malaria infection, using these to estimate variation in malaria risk on Porto Santo, and found some congruence with previously identified environmental risk factors on Tenerife. We also found a negative association between malaria infection and a TLR4 variant in Tenerife. In contrast, one of the GWAS SNPs showed an association with malaria risk in Porto Santo, but in the opposite direction to that found in the Canary Islands GWAS. Together, these findings suggest that disease-driven local adaptation may be an important factor in shaping variation among island populations.
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Affiliation(s)
| | | | - Catalina González‐Quevedo
- School of Biological SciencesUniversity of East AngliaNorwichUK
- Grupo Ecología y Evolución de VertebradosInstituto de BiologíaFacultad de Ciencias Exactas y NaturalesUniversidad de AntioquiaMedellínColombia
| | - Molly Dunne
- School of Biological SciencesUniversity of East AngliaNorwichUK
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6
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Toews SD, Wellband KW, Dixon B, Heath DD. Variation in juvenile Chinook salmon (Oncorhynchus tshawytscha) transcription profiles among and within eight population crosses from British Columbia, Canada. Mol Ecol 2019; 28:1890-1903. [DOI: 10.1111/mec.15025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Revised: 01/02/2019] [Accepted: 01/07/2019] [Indexed: 12/17/2022]
Affiliation(s)
- Shelby D. Toews
- Great Lakes Institute for Environmental Research University of Windsor Windsor Ontario Canada
| | - Kyle W. Wellband
- Great Lakes Institute for Environmental Research University of Windsor Windsor Ontario Canada
- Institute de Biologie Intégrative et des SystèmesUniversité LavalQuébec Québec Canada
| | - Brian Dixon
- Department of Biology University of Waterloo Waterloo Ontario Canada
| | - Daniel D. Heath
- Great Lakes Institute for Environmental Research University of Windsor Windsor Ontario Canada
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7
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Gerdol M, Lucente D, Buonocore F, Poerio E, Scapigliati G, Mattiucci S, Pallavicini A, Cimmaruta R. Molecular and Structural Characterization of MHC Class II β Genes Reveals High Diversity in the Cold-Adapted Icefish Chionodraco hamatus. Sci Rep 2019; 9:5523. [PMID: 30940855 DOI: 10.1038/s41598-019-42003-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 03/21/2019] [Indexed: 01/04/2023] Open
Abstract
This study reports the presence of two distinct MHC class II β genes in the Antarctic icefish Chionodraco hamatus, belonging to the classical (ChhaDAB) and nonclassical (ChhaDBB) evolutionary lineages. By the application of targeted sequencing approach, a remarkable molecular diversity in the exon 2 sequence of the highly expressed gene ChhaDAB has been observed, resulting in an estimate of 92 different variants translated in 87 different peptides from 54 analysed icefish individuals. A highly conservative estimate, based on a 95% sequence identity threshold clustering, translate this variability in 41 different peptide clusters belonging to four different clades and showing the signature of different kinds of selection. In stark contrast, the poorly expressed ChhaDBB gene displayed a very low level of molecular diversity within exon 2, in agreement with expectations for a nonclassical MHC class II β gene.
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8
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Sylvester EVA, Beiko RG, Bentzen P, Paterson I, Horne JB, Watson B, Lehnert S, Duffy S, Clément M, Robertson MJ, Bradbury IR. Environmental extremes drive population structure at the northern range limit of Atlantic salmon in North America. Mol Ecol 2018; 27:4026-4040. [PMID: 30152128 DOI: 10.1111/mec.14849] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 08/16/2018] [Accepted: 08/22/2018] [Indexed: 12/18/2022]
Abstract
Conservation of exploited species requires an understanding of both genetic diversity and the dominant structuring forces, particularly near range limits, where climatic variation can drive rapid expansions or contractions of geographic range. Here, we examine population structure and landscape associations in Atlantic salmon (Salmo salar) across a heterogeneous landscape near the northern range limit in Labrador, Canada. Analysis of two amplicon-based data sets containing 101 microsatellites and 376 single nucleotide polymorphisms (SNPs) from 35 locations revealed clear differentiation between populations spawning in rivers flowing into a large marine embayment (Lake Melville) compared to coastal populations. The mechanisms influencing the differentiation of embayment populations were investigated using both multivariate and machine-learning landscape genetic approaches. We identified temperature as the strongest correlate with genetic structure, particularly warm temperature extremes and wider annual temperature ranges. The genomic basis of this divergence was further explored using a subset of locations (n = 17) and a 220K SNP array. SNPs associated with spatial structuring and temperature mapped to a diverse set of genes and molecular pathways, including regulation of gene expression, immune response, and cell development and differentiation. The results spanning molecular marker types and both novel and established methods clearly show climate-associated, fine-scale population structure across an environmental gradient in Atlantic salmon near its range limit in North America, highlighting valuable approaches for predicting population responses to climate change and managing species sustainability.
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Affiliation(s)
- Emma V A Sylvester
- Science Branch, Department of Fisheries and Oceans Canada, St. John's, NL, Canada
| | - Robert G Beiko
- Faculty of Computer Science, Dalhousie University, Halifax, NS, Canada
| | - Paul Bentzen
- Marine Gene Probe Laboratory, Department of Biology, Dalhousie University, Halifax, NS, Canada
| | - Ian Paterson
- Faculty of Computer Science, Dalhousie University, Halifax, NS, Canada
| | - John B Horne
- University of Southern Mississippi Gulf Coast Research Laboratory, Ocean Springs, MS, Canada
| | - Beth Watson
- Marine Gene Probe Laboratory, Department of Biology, Dalhousie University, Halifax, NS, Canada
| | - Sarah Lehnert
- Science Branch, Department of Fisheries and Oceans Canada, St. John's, NL, Canada
| | - Steven Duffy
- Science Branch, Department of Fisheries and Oceans Canada, St. John's, NL, Canada
| | - Marie Clément
- Centre for Fisheries Ecosystems Research, Fisheries and Marine Institute, Memorial University of Newfoundland, St. John's, NL, Canada.,Labrador Institute, Memorial University of Newfoundland, Happy Valley-Goose Bay, NL, Canada
| | - Martha J Robertson
- Science Branch, Department of Fisheries and Oceans Canada, St. John's, NL, Canada
| | - Ian R Bradbury
- Science Branch, Department of Fisheries and Oceans Canada, St. John's, NL, Canada.,Faculty of Computer Science, Dalhousie University, Halifax, NS, Canada.,Marine Gene Probe Laboratory, Department of Biology, Dalhousie University, Halifax, NS, Canada
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9
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DeFilippo LB, Schindler DE, Carter JL, Walsworth TE, Cline TJ, Larson WA, Buehrens T. Associations of stream geomorphic conditions and prevalence of alternative reproductive tactics among sockeye salmon populations. J Evol Biol 2018; 31:239-253. [PMID: 29194863 DOI: 10.1111/jeb.13217] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Revised: 10/24/2017] [Accepted: 11/21/2017] [Indexed: 12/22/2022]
Abstract
In many species, males may exhibit alternative life histories to circumvent the costs of intrasexual competition and female courtship. While the evolution and underlying genetic and physiological mechanisms behind alternative reproductive tactics are well studied, there has been less consideration of the ecological factors that regulate their prevalence. Here, we examine six decades of age composition records from thirty-six populations of sockeye salmon (Oncorhynchus nerka) to quantify associations between spawning habitat characteristics and the prevalence of precocious sneakers known as 'jacks'. Jack prevalence was independent of neutral genetic structure among stream populations, but varied among habitat types and as a function of continuous geomorphic characteristics. Jacks were more common in streams relative to beaches and rivers, and their prevalence was negatively associated with stream width, depth, elevation, slope and area, but positively related to bank cover. Behavioural observations showed that jacks made greater use of banks, wood and shallows than guard males, indicating that their reproductive success depends on the availability of such refuges. Our results emphasize the role of the physical habitat in shaping reproductive tactic frequencies among populations, likely through local adaptation in response to variable fitness expectations under different geomorphic conditions.
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Affiliation(s)
- L B DeFilippo
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - D E Schindler
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - J L Carter
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - T E Walsworth
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - T J Cline
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA
| | - W A Larson
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA.,U. S. Geological Survey, Wisconsin Cooperative Fishery Research Unit, University of Wisconsin-Stevens Point, Stevens Point, WI, USA
| | - T Buehrens
- School of Aquatic and Fishery Sciences, University of Washington, Seattle, WA, USA.,Washington Department of Fish and Wildlife, Olympia, WA, USA
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10
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Gordeeva NV, Salmenkova EA. Genetic markers of adaptive processes in the Far Eastern pink salmon Oncorhynchus gorbuscha: Allelic diversity at the locus of major histocompatibility complex MHC I-A1. RUSS J GENET+ 2017. [DOI: 10.1134/s1022795417110035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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11
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Baillie SM, Hemstock RR, Muir AM, Krueger CC, Bentzen P. Small-scale intraspecific patterns of adaptive immunogenetic polymorphisms and neutral variation in Lake Superior lake trout. Immunogenetics 2018; 70:53-66. [PMID: 28547520 DOI: 10.1007/s00251-017-0996-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 04/26/2017] [Indexed: 10/19/2022]
Abstract
Many fishes express high levels of intraspecific variability, often linked to resource partitioning. Several studies show that a species' evolutionary trajectory of adaptive divergence can undergo reversals caused by changes in its environment. Such a reversal in neutral genetic and morphological variation among lake trout Salvelinus namaycush ecomorphs appears to be underway in Lake Superior. However, a water depth gradient in neutral genetic divergence was found to be associated with intraspecific diversity in the lake. To investigate patterns of adaptive immunogenetic variation among lake trout ecomorphs, we used Illumina high-throughput sequencing. The population's genetic structure of the major histocompatibility complex (MHC Class IIβ exon 2) and 18 microsatellite loci were compared to disentangle neutral and selective processes at a small geographic scale. Both MHC and microsatellite variation were partitioned more by water depth stratum than by ecomorph. Several metrics showed strong clustering by water depth in MHC alleles, but not microsatellites. We report a 75% increase in the number of MHC alleles shared between the predominant shallow and deep water ecomorphs since a previous lake trout MHC study at the same locale (c. 1990s data). This result is consistent with the reverse speciation hypothesis, although adaptive MHC polymorphisms persist along an ecological gradient. Finally, results suggested that the lake trout have multiple copies of the MHC II locus consistent with a historic genomic duplication event. Our findings indicated that conservation approaches for this species could focus on managing various ecological habitats by depth, in addition to regulating the fisheries specific to ecomorphs.
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