1
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Masila EM, Ogada SO, Ogali IN, Kennedy GM, Too EK, Ommeh CS. Mitochondrial DNA D-Loop Polymorphisms among the Galla Goats Reveals Multiple Maternal Origins with Implication on the Functional Diversity of the HSP70 Gene. Genet Res (Camb) 2024; 2024:5564596. [PMID: 38348366 PMCID: PMC10861283 DOI: 10.1155/2024/5564596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 01/12/2024] [Accepted: 01/18/2024] [Indexed: 02/15/2024] Open
Abstract
Despite much attention given to the history of goat evolution in Kenya, information on the origin, demographic history, dispersal route, and genetic diversity of Galla goats remains unclear. Here, we examined the genetic background, diversity, demographic history, and population genetic variation of Galla goats using mtDNA D-loop and HSP70 single-nucleotide polymorphism markers. The results revealed 90 segregating sites and 68 haplotypes in a 600-bp mtDNA D-loop sequence. The overall mean mitochondrial haplotype diversity was 0.993. The haplotype diversities ranged between 0.8939 ± 0.0777 and 1.0000 ± 0.0221 in all populations supporting high genetic diversity. Mitochondrial phylogenetic analysis revealed three Galla goat haplogroups (A, G, and D), supporting multiple maternal ancestries, of which haplogroup A was the most predominant. Analysis of molecular variance (AMOVA) showed considerable variation within populations at 94.39%, evidence of high genetic diversity. Bimodal mismatch distribution patterns were observed while most populations recorded negative results for Tajima and Fu's Fs neutrality tests supporting population expansion. Genetic variation among populations was also confirmed using HSP70 gene fragment sequences, where six polymorphic sites which defined 21 haplotypes were discovered. Analysis of molecular variance revealed a significant FST index value of 0.134 and a high FIS index value of 0.746, an indication of inbreeding. This information will pave the way for conservation strategies and informed breeding to improve Galla or other goat breeds for climate-smart agriculture.
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Affiliation(s)
- Ednah M. Masila
- Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Juja, Kenya
- Veterinary Science Research Institute (VSRI), Kenya Agricultural Livestock and Research Organization (KALRO), P.O. Box 32-00902, Nairobi, Kenya
| | - Stephen O. Ogada
- Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Juja, Kenya
| | - Irene N. Ogali
- Veterinary Science Research Institute (VSRI), Kenya Agricultural Livestock and Research Organization (KALRO), P.O. Box 32-00902, Nairobi, Kenya
| | - Grace M. Kennedy
- Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Juja, Kenya
| | - Eric K. Too
- Veterinary Science Research Institute (VSRI), Kenya Agricultural Livestock and Research Organization (KALRO), P.O. Box 32-00902, Nairobi, Kenya
| | - Cecily S. Ommeh
- Institute for Biotechnology Research, Jomo Kenyatta University of Agriculture and Technology, P.O. Box 62000-00200, Juja, Kenya
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2
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Wolff R, Garud NR. Pervasive selective sweeps across human gut microbiomes. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.22.573162. [PMID: 38187688 PMCID: PMC10769429 DOI: 10.1101/2023.12.22.573162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
The human gut microbiome is composed of a highly diverse consortia of species which are continually evolving within and across hosts. The ability to identify adaptations common to many host gut microbiomes would not only reveal shared selection pressures across hosts, but also key drivers of functional differentiation of the microbiome that may affect community structure and host traits. However, to date there has not been a systematic scan for adaptations that have spread across host microbiomes. Here, we develop a novel selection scan statistic, named the integrated linkage disequilibrium score (iLDS), that can detect the spread of adaptive haplotypes across host microbiomes via migration and horizontal gene transfer. Specifically, iLDS leverages signals of hitchhiking of deleterious variants with the beneficial variant, a common feature of adaptive evolution. We find that iLDS is capable of detecting simulated and known cases of selection, and moreover is robust to potential confounders that can also elevate LD. Application of the statistic to ~20 common commensal gut species from a large cohort of healthy, Western adults reveals pervasive spread of selected alleles across human microbiomes mediated by horizontal gene transfer. Among the candidate selective sweeps recovered by iLDS is an enrichment for genes involved in the metabolism of maltodextrin, a synthetic starch that has recently become a widespread component of Western diets. In summary, we demonstrate that selective sweeps across host microbiomes are a common feature of the evolution of the human gut microbiome.
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Affiliation(s)
- Richard Wolff
- Department of Ecology and Evolutionary Biology, UCLA
| | - Nandita R. Garud
- Department of Ecology and Evolutionary Biology, UCLA
- Department of Human Genetics, UCLA
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3
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Panigrahi M, Rajawat D, Nayak SS, Ghildiyal K, Sharma A, Jain K, Lei C, Bhushan B, Mishra BP, Dutt T. Landmarks in the history of selective sweeps. Anim Genet 2023; 54:667-688. [PMID: 37710403 DOI: 10.1111/age.13355] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2023] [Accepted: 08/28/2023] [Indexed: 09/16/2023]
Abstract
Half a century ago, a seminal article on the hitchhiking effect by Smith and Haigh inaugurated the concept of the selection signature. Selective sweeps are characterised by the rapid spread of an advantageous genetic variant through a population and hence play an important role in shaping evolution and research on genetic diversity. The process by which a beneficial allele arises and becomes fixed in a population, leading to a increase in the frequency of other linked alleles, is known as genetic hitchhiking or genetic draft. Kimura's neutral theory and hitchhiking theory are complementary, with Kimura's neutral evolution as the 'null model' and positive selection as the 'signal'. Both are widely accepted in evolution, especially with genomics enabling precise measurements. Significant advances in genomic technologies, such as next-generation sequencing, high-density SNP arrays and powerful bioinformatics tools, have made it possible to systematically investigate selection signatures in a variety of species. Although the history of selection signatures is relatively recent, progress has been made in the last two decades, owing to the increasing availability of large-scale genomic data and the development of computational methods. In this review, we embark on a journey through the history of research on selective sweeps, ranging from early theoretical work to recent empirical studies that utilise genomic data.
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Affiliation(s)
- Manjit Panigrahi
- Division of Animal Genetics, Indian Veterinary Research Institute, Bareilly, India
| | - Divya Rajawat
- Division of Animal Genetics, Indian Veterinary Research Institute, Bareilly, India
| | | | - Kanika Ghildiyal
- Division of Animal Genetics, Indian Veterinary Research Institute, Bareilly, India
| | - Anurodh Sharma
- Division of Animal Genetics, Indian Veterinary Research Institute, Bareilly, India
| | - Karan Jain
- Division of Animal Genetics, Indian Veterinary Research Institute, Bareilly, India
| | - Chuzhao Lei
- College of Animal Science and Technology, Northwest A&F University, Yangling, Shaanxi, China
| | - Bharat Bhushan
- Division of Animal Genetics, Indian Veterinary Research Institute, Bareilly, India
| | - Bishnu Prasad Mishra
- Division of Animal Biotechnology, ICAR-National Bureau of Animal Genetic Resources, Karnal, India
| | - Triveni Dutt
- Livestock Production and Management Section, Indian Veterinary Research Institute, Bareilly, India
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4
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Yelmen B, Decelle A, Boulos LL, Szatkownik A, Furtlehner C, Charpiat G, Jay F. Deep convolutional and conditional neural networks for large-scale genomic data generation. PLoS Comput Biol 2023; 19:e1011584. [PMID: 37903158 PMCID: PMC10635570 DOI: 10.1371/journal.pcbi.1011584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 11/09/2023] [Accepted: 10/09/2023] [Indexed: 11/01/2023] Open
Abstract
Applications of generative models for genomic data have gained significant momentum in the past few years, with scopes ranging from data characterization to generation of genomic segments and functional sequences. In our previous study, we demonstrated that generative adversarial networks (GANs) and restricted Boltzmann machines (RBMs) can be used to create novel high-quality artificial genomes (AGs) which can preserve the complex characteristics of real genomes such as population structure, linkage disequilibrium and selection signals. However, a major drawback of these models is scalability, since the large feature space of genome-wide data increases computational complexity vastly. To address this issue, we implemented a novel convolutional Wasserstein GAN (WGAN) model along with a novel conditional RBM (CRBM) framework for generating AGs with high SNP number. These networks implicitly learn the varying landscape of haplotypic structure in order to capture complex correlation patterns along the genome and generate a wide diversity of plausible haplotypes. We performed comparative analyses to assess both the quality of these generated haplotypes and the amount of possible privacy leakage from the training data. As the importance of genetic privacy becomes more prevalent, the need for effective privacy protection measures for genomic data increases. We used generative neural networks to create large artificial genome segments which possess many characteristics of real genomes without substantial privacy leakage from the training dataset. In the near future, with further improvements in haplotype quality and privacy preservation, large-scale artificial genome databases can be assembled to provide easily accessible surrogates of real databases, allowing researchers to conduct studies with diverse genomic data within a safe ethical framework in terms of donor privacy.
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Affiliation(s)
- Burak Yelmen
- Université Paris-Saclay, CNRS, INRIA, LISN, Paris, France
- University of Tartu, Institute of Genomics, Tartu, Estonia
| | - Aurélien Decelle
- Université Paris-Saclay, CNRS, INRIA, LISN, Paris, France
- Universidad Complutense de Madrid, Departamento de Física Teórica, Madrid, Spain
| | - Leila Lea Boulos
- Université Paris-Saclay, CNRS, INRIA, LISN, Paris, France
- Université d’Évry Val-d’Essonne, Évry-Courcouronnes, France
| | | | | | | | - Flora Jay
- Université Paris-Saclay, CNRS, INRIA, LISN, Paris, France
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5
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Bringloe TT, Fort A, Inaba M, Sulpice R, Ghriofa CN, Mols‐Mortensen A, Filbee‐Dexter K, Vieira C, Kawai H, Hanyuda T, Krause‐Jensen D, Olesen B, Starko S, Verbruggen H. Whole genome population structure of North Atlantic kelp confirms high-latitude glacial refugia. Mol Ecol 2022; 31:6473-6488. [PMID: 36200326 PMCID: PMC10091776 DOI: 10.1111/mec.16714] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 09/21/2022] [Indexed: 01/13/2023]
Abstract
Coastal refugia during the Last Glacial Maximum (~21,000 years ago) have been hypothesized at high latitudes in the North Atlantic, suggesting marine populations persisted through cycles of glaciation and are potentially adapted to local environments. Here, whole-genome sequencing was used to test whether North Atlantic marine coastal populations of the kelp Alaria esculenta survived in the area of southwestern Greenland during the Last Glacial Maximum. We present the first annotated genome for A. esculenta and call variant positions in 54 individuals from populations in Atlantic Canada, Greenland, Faroe Islands, Norway and Ireland. Differentiation across populations was reflected in ~1.9 million single nucleotide polymorphisms, which further revealed mixed ancestry in the Faroe Islands individuals between putative Greenlandic and European lineages. Time-calibrated organellar phylogenies suggested Greenlandic populations were established during the last interglacial period more than 100,000 years ago, and that the Faroe Islands population was probably established following the Last Glacial Maximum. Patterns in population statistics, including nucleotide diversity, minor allele frequencies, heterozygosity and linkage disequilibrium decay, nonetheless suggested glaciation reduced Canadian Atlantic and Greenlandic populations to small effective sizes during the most recent glaciation. Functional differentiation was further reflected in exon read coverage, which revealed expansions unique to Greenland in 337 exons representing 162 genes, and a modest degree of exon loss (103 exons from 56 genes). Altogether, our genomic results provide strong evidence that A. esculenta populations were resilient to past climatic fluctuations related to glaciations and that high-latitude populations are potentially already adapted to local conditions as a result.
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Affiliation(s)
| | - Antoine Fort
- Plant Systems Biology Lab, Ryan Institute, SFI MaREI Centre for Climate, Energy and Marine, School of Natural SciencesNational University of Ireland GalwayGalwayIreland
- Present address:
Department of Life and Physical SciencesAthlone Institute of TechnologyAthloneIreland
| | - Masami Inaba
- Plant Systems Biology Lab, Ryan Institute, SFI MaREI Centre for Climate, Energy and Marine, School of Natural SciencesNational University of Ireland GalwayGalwayIreland
| | - Ronan Sulpice
- Plant Systems Biology Lab, Ryan Institute, SFI MaREI Centre for Climate, Energy and Marine, School of Natural SciencesNational University of Ireland GalwayGalwayIreland
| | - Cliodhna Ní Ghriofa
- Business Development ManagerMarine Innovation Development Centre Páirc Na MaraGalwayIreland
| | | | - Karen Filbee‐Dexter
- School of Biological Sciences and UWA Oceans InstituteUniversity of Western AustraliaPerthWestern AustraliaAustralia
| | - Christophe Vieira
- Kobe University Research Center for Inland SeasKobe UniversityKobeJapan
| | - Hiroshi Kawai
- Kobe University Research Center for Inland SeasKobe UniversityKobeJapan
| | - Takeaki Hanyuda
- School of Marine BiosciencesKitasato UniversitySagamiharaJapan
| | - Dorte Krause‐Jensen
- Department of EcoscienceAarhus UniversityAarhusDenmark
- Arctic Research CenterAarhus UniversityAarhusDenmark
| | | | - Samuel Starko
- Department of BiologyUniversity of VictoriaVictoriaCanada
| | - Heroen Verbruggen
- School of BioSciencesUniversity of MelbourneParkvilleVictoriaAustralia
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6
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Schlichta F, Moinet A, Peischl S, Excoffier L. The Impact of Genetic Surfing on Neutral Genomic Diversity. Mol Biol Evol 2022; 39:msac249. [PMID: 36403964 PMCID: PMC9703594 DOI: 10.1093/molbev/msac249] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Range expansions have been common in the history of most species. Serial founder effects and subsequent population growth at expansion fronts typically lead to a loss of genomic diversity along the expansion axis. A frequent consequence is the phenomenon of "gene surfing," where variants located near the expanding front can reach high frequencies or even fix in newly colonized territories. Although gene surfing events have been characterized thoroughly for a specific locus, their effects on linked genomic regions and the overall patterns of genomic diversity have been little investigated. In this study, we simulated the evolution of whole genomes during several types of 1D and 2D range expansions differing by the extent of migration, founder events, and recombination rates. We focused on the characterization of local dips of diversity, or "troughs," taken as a proxy for surfing events. We find that, for a given recombination rate, once we consider the amount of diversity lost since the beginning of the expansion, it is possible to predict the initial evolution of trough density and their average width irrespective of the expansion condition. Furthermore, when recombination rates vary across the genome, we find that troughs are over-represented in regions of low recombination. Therefore, range expansions can leave local and global genomic signatures often interpreted as evidence of past selective events. Given the generality of our results, they could be used as a null model for species having gone through recent expansions, and thus be helpful to correctly interpret many evolutionary biology studies.
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Affiliation(s)
- Flávia Schlichta
- Computational and Molecular Population Genetics lab, Institute of Ecology and Evolution, University of Bern, Baltzerstrasse 6, 3012 Bern, Switzerland
- Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
| | - Antoine Moinet
- Computational and Molecular Population Genetics lab, Institute of Ecology and Evolution, University of Bern, Baltzerstrasse 6, 3012 Bern, Switzerland
- Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
- Interfaculty Bioinformatics Unit, University of Bern, Baltzerstrasse 6, 3012 Bern, Switzerland
| | - Stephan Peischl
- Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
- Interfaculty Bioinformatics Unit, University of Bern, Baltzerstrasse 6, 3012 Bern, Switzerland
| | - Laurent Excoffier
- Computational and Molecular Population Genetics lab, Institute of Ecology and Evolution, University of Bern, Baltzerstrasse 6, 3012 Bern, Switzerland
- Swiss Institute of Bioinformatics, 1015 Lausanne, Switzerland
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7
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Kumar H, Panigrahi M, Panwar A, Rajawat D, Nayak SS, Saravanan KA, Kaisa K, Parida S, Bhushan B, Dutt T. Machine-Learning Prospects for Detecting Selection Signatures Using Population Genomics Data. J Comput Biol 2022; 29:943-960. [PMID: 35639362 DOI: 10.1089/cmb.2021.0447] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Natural selection has been given a lot of attention because it relates to the adaptation of populations to their environments, both biotic and abiotic. An allele is selected when it is favored by natural selection. Consequently, the favored allele increases in frequency in the population and neighboring linked variation diminishes, causing so-called selective sweeps. A high-throughput genomic sequence allows one to disentangle the evolutionary forces at play in populations. With the development of high-throughput genome sequencing technologies, it has become easier to detect these selective sweeps/selection signatures. Various methods can be used to detect selective sweeps, from simple implementations using summary statistics to complex statistical approaches. One of the important problems of these statistical models is the potential to provide inaccurate results when their assumptions are violated. The use of machine learning (ML) in population genetics has been introduced as an alternative method of detecting selection by treating the problem of detecting selection signatures as a classification problem. Since the availability of population genomics data is increasing, researchers may incorporate ML into these statistical models to infer signatures of selection with higher predictive accuracy and better resolution. This article describes how ML can be used to aid in detecting and studying natural selection patterns using population genomic data.
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Affiliation(s)
- Harshit Kumar
- Divisions of Animal Genetics, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - Manjit Panigrahi
- Divisions of Animal Genetics, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - Anuradha Panwar
- Divisions of Animal Genetics, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - Divya Rajawat
- Divisions of Animal Genetics, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - Sonali Sonejita Nayak
- Divisions of Animal Genetics, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - K A Saravanan
- Divisions of Animal Genetics, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - Kaiho Kaisa
- Divisions of Animal Genetics, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - Subhashree Parida
- Divisions of Pharmacology and Toxicology, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - Bharat Bhushan
- Divisions of Animal Genetics, ICAR-Indian Veterinary Research Institute, Izatnagar, India
| | - Triveni Dutt
- Livestock Production and Management Section, ICAR-Indian Veterinary Research Institute, Izatnagar, India
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8
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Semagn K, Iqbal M, Alachiotis N, N'Diaye A, Pozniak C, Spaner D. Genetic diversity and selective sweeps in historical and modern Canadian spring wheat cultivars using the 90K SNP array. Sci Rep 2021; 11:23773. [PMID: 34893626 PMCID: PMC8664822 DOI: 10.1038/s41598-021-02666-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 11/22/2021] [Indexed: 12/14/2022] Open
Abstract
Previous molecular characterization studies conducted in Canadian wheat cultivars shed some light on the impact of plant breeding on genetic diversity, but the number of varieties and markers used was small. Here, we used 28,798 markers of the wheat 90K single nucleotide polymorphisms to (a) assess the extent of genetic diversity, relationship, population structure, and divergence among 174 historical and modern Canadian spring wheat varieties registered from 1905 to 2018 and 22 unregistered lines (hereinafter referred to as cultivars), and (b) identify genomic regions that had undergone selection. About 91% of the pairs of cultivars differed by 20-40% of the scored alleles, but only 7% of the pairs had kinship coefficients of < 0.250, suggesting the presence of a high proportion of redundancy in allelic composition. Although the 196 cultivars represented eight wheat classes, our results from phylogenetic, principal component, and the model-based population structure analyses revealed three groups, with no clear structure among most wheat classes, breeding programs, and breeding periods. FST statistics computed among different categorical variables showed little genetic differentiation (< 0.05) among breeding periods and breeding programs, but a diverse level of genetic differentiation among wheat classes and predicted groups. Diversity indices were the highest and lowest among cultivars registered from 1970 to 1980 and from 2011 to 2018, respectively. Using two outlier detection methods, we identified from 524 to 2314 SNPs and 41 selective sweeps of which some are close to genes with known phenotype, including plant height, photoperiodism, vernalization, gluten strength, and disease resistance.
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Affiliation(s)
- Kassa Semagn
- Department of Agricultural, Food, and Nutritional Science, 4-10 Agriculture-Forestry Centre, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
| | - Muhammad Iqbal
- Department of Agricultural, Food, and Nutritional Science, 4-10 Agriculture-Forestry Centre, University of Alberta, Edmonton, AB, T6G 2P5, Canada
| | - Nikolaos Alachiotis
- Faculty of Electrical Engineering, Mathematics and Computer Science, University of Twente, 3230, Enschede, OV, The Netherlands
| | - Amidou N'Diaye
- Crop Development Centre and Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
| | - Curtis Pozniak
- Crop Development Centre and Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, SK, S7N 5A8, Canada
| | - Dean Spaner
- Department of Agricultural, Food, and Nutritional Science, 4-10 Agriculture-Forestry Centre, University of Alberta, Edmonton, AB, T6G 2P5, Canada.
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9
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Bourgeois YXC, Warren BH. An overview of current population genomics methods for the analysis of whole-genome resequencing data in eukaryotes. Mol Ecol 2021; 30:6036-6071. [PMID: 34009688 DOI: 10.1111/mec.15989] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Revised: 04/26/2021] [Accepted: 05/11/2021] [Indexed: 01/01/2023]
Abstract
Characterizing the population history of a species and identifying loci underlying local adaptation is crucial in functional ecology, evolutionary biology, conservation and agronomy. The constant improvement of high-throughput sequencing techniques has facilitated the production of whole genome data in a wide range of species. Population genomics now provides tools to better integrate selection into a historical framework, and take into account selection when reconstructing demographic history. However, this improvement has come with a profusion of analytical tools that can confuse and discourage users. Such confusion limits the amount of information effectively retrieved from complex genomic data sets, and impairs the diffusion of the most recent analytical tools into fields such as conservation biology. It may also lead to redundancy among methods. To address these isssues, we propose an overview of more than 100 state-of-the-art methods that can deal with whole genome data. We summarize the strategies they use to infer demographic history and selection, and discuss some of their limitations. A website listing these methods is available at www.methodspopgen.com.
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Affiliation(s)
| | - Ben H Warren
- Institut de Systématique, Evolution, Biodiversité (ISYEB), Muséum National d'Histoire Naturelle, CNRS, Sorbonne Université, EPHE, UA, CP 51, Paris, France
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10
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Guirao‐Rico S, González J. Benchmarking the performance of Pool-seq SNP callers using simulated and real sequencing data. Mol Ecol Resour 2021; 21:1216-1229. [PMID: 33534960 PMCID: PMC8251607 DOI: 10.1111/1755-0998.13343] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 12/21/2020] [Accepted: 01/27/2021] [Indexed: 12/13/2022]
Abstract
Population genomics is a fast-developing discipline with promising applications in a growing number of life sciences fields. Advances in sequencing technologies and bioinformatics tools allow population genomics to exploit genome-wide information to identify the molecular variants underlying traits of interest and the evolutionary forces that modulate these variants through space and time. However, the cost of genomic analyses of multiple populations is still too high to address them through individual genome sequencing. Pooling individuals for sequencing can be a more effective strategy in Single Nucleotide Polymorphism (SNP) detection and allele frequency estimation because of a higher total coverage. However, compared to individual sequencing, SNP calling from pools has the additional difficulty of distinguishing rare variants from sequencing errors, which is often avoided by establishing a minimum threshold allele frequency for the analysis. Finding an optimal balance between minimizing information loss and reducing sequencing costs is essential to ensure the success of population genomics studies. Here, we have benchmarked the performance of SNP callers for Pool-seq data, based on different approaches, under different conditions, and using computer simulations and real data. We found that SNP callers performance varied for allele frequencies up to 0.35. We also found that SNP callers based on Bayesian (SNAPE-pooled) or maximum likelihood (MAPGD) approaches outperform the two heuristic callers tested (VarScan and PoolSNP), in terms of the balance between sensitivity and FDR both in simulated and sequencing data. Our results will help inform the selection of the most appropriate SNP caller not only for large-scale population studies but also in cases where the Pool-seq strategy is the only option, such as in metagenomic or polyploid studies.
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Affiliation(s)
- Sara Guirao‐Rico
- Institute of Evolutionary BiologyCSIC‐Universitat Pompeu FabraBarcelonaSpain
| | - Josefa González
- Institute of Evolutionary BiologyCSIC‐Universitat Pompeu FabraBarcelonaSpain
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11
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Dadshani S, Mathew B, Ballvora A, Mason AS, Léon J. Detection of breeding signatures in wheat using a linkage disequilibrium-corrected mapping approach. Sci Rep 2021; 11:5527. [PMID: 33750919 PMCID: PMC7970893 DOI: 10.1038/s41598-021-85226-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 02/25/2021] [Indexed: 01/31/2023] Open
Abstract
Marker assisted breeding, facilitated by reference genome assemblies, can help to produce cultivars adapted to changing environmental conditions. However, anomalous linkage disequilibrium (LD), where single markers show high LD with markers on other chromosomes but low LD with adjacent markers, is a serious impediment for genetic studies. We used a LD-correction approach to overcome these drawbacks, correcting the physical position of markers derived from 15 and 135 K arrays in a diversity panel of bread wheat representing 50 years of breeding history. We detected putative mismapping of 11.7% markers and improved the physical alignment of 5.4% markers. Population analysis indicated reduced genetic diversity over time as a result of breeding efforts. By analysis of outlier loci and allele frequency change over time we traced back the 2NS/2AS translocation of Aegilops ventricosa to one cultivar, "Cardos" (registered in 1998) which was the first among the panel to contain this translocation. A "selective sweep" for this important translocation region on chromosome 2AS was found, putatively linked to plant response to biotic stress factors. Our approach helps in overcoming the drawbacks of incorrectly anchored markers on the wheat reference assembly and facilitates detection of selective sweeps for important agronomic traits.
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Affiliation(s)
- Said Dadshani
- Institute of Crop Science and Resource Conservation (INRES), Plant Breeding, University of Bonn, Bonn, Germany.
| | - Boby Mathew
- Bayer CropScience, Monheim am Rhein, Germany
| | - Agim Ballvora
- Institute of Crop Science and Resource Conservation (INRES), Plant Breeding, University of Bonn, Bonn, Germany
| | - Annaliese S Mason
- Institute of Crop Science and Resource Conservation (INRES), Plant Breeding, University of Bonn, Bonn, Germany
| | - Jens Léon
- Institute of Crop Science and Resource Conservation (INRES), Plant Breeding, University of Bonn, Bonn, Germany.
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12
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Gu H, Zhu T, Li X, Chen Y, Wang L, Lv X, Yang W, Jia Y, Jiang Z, Qu L. A joint analysis strategy reveals genetic changes associated with artificial selection between egg-type and meat-type ducks. Anim Genet 2020; 51:890-898. [PMID: 33058234 DOI: 10.1111/age.13014] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/23/2020] [Indexed: 12/16/2022]
Abstract
Egg-type ducks and meat-type ducks are predominantly commercial or indigenous and have been subjected to artificial directional selection. These two duck types differ substantially in body shape, production performance and reproductivity. However, the genetic changes associated with phenotypic differences remain unclear. Here, we compared the two duck types at the genomic and transcriptomic levels. We identified a large number of SNPs and genes in genomic divergent regions in terms of FST and θπ values. The corresponding genes were mainly enriched in embryonic development function and metabolic pathway. RNA-seq analysis also revealed differential gene expression in the liver and gonads. The differentially expressed genes were functionally associated with signal transmission and substance metabolism respectively. Furthermore, we found that seven genes were related to differentiation between the two types by both g genome and transcriptome analysis and were plausible candidate genes. These genes were annotated to GO categories of cell development and disease immunity. These findings will enable a better understanding of the artificial selection history of meat and egg ducks and provide a valuable resource for future research on the breeding of these two lineages.
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Affiliation(s)
- H Gu
- Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Yuanmingyuan West Road 2#, Beijing, 100193, China
| | - T Zhu
- Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Yuanmingyuan West Road 2#, Beijing, 100193, China
| | - X Li
- College of Animal Science and Technology, Shandong Agricultural University, Daizong Street #61, Tai'an, Shandong, 271018, China
| | - Y Chen
- Beijing Municipal General Station of Animal Science, Beiyuan Road 15A#, Beijing, 100107, China
| | - L Wang
- Beijing Municipal General Station of Animal Science, Beiyuan Road 15A#, Beijing, 100107, China
| | - X Lv
- Beijing Municipal General Station of Animal Science, Beiyuan Road 15A#, Beijing, 100107, China
| | - W Yang
- Beijing Municipal General Station of Animal Science, Beiyuan Road 15A#, Beijing, 100107, China
| | - Y Jia
- Institute of Animal Science, Chinese Academy of Agricultural Sciences, Yuanmingyuan West Road 2#, Beijing, 100193, China
| | - Z Jiang
- Department of Animal Sciences, center for Reproductive Biology, Veterinary and Biomedical Research Building, Washington State University, Pullman, Washington, 647010, USA
| | - L Qu
- Department of Animal Genetics and Breeding, National Engineering Laboratory for Animal Breeding, College of Animal Science and Technology, China Agricultural University, Yuanmingyuan West Road 2#, Beijing, 100193, China
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