1
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Gao M, Hua T, Niu G, Masabni J, Dewalt W. A locus-dependent mixed inheritance in the segmental allohexaploid sweetpotato ( Ipomoea batatas [L.] Lam). FRONTIERS IN PLANT SCIENCE 2024; 15:1398081. [PMID: 38863536 PMCID: PMC11165125 DOI: 10.3389/fpls.2024.1398081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 05/06/2024] [Indexed: 06/13/2024]
Abstract
Two interrelated aspects of the sweetpotato genome, its polyploid origin and inheritance type, remain uncertain. We recently proposed a segmental allohexaploid sweetpotato and thus sought to clarify its inheritance type by direct analyses of homoeolog segregations at selected single-copy loci. For such analyses, we developed a digital quantitative PCR genotyping method using one nondiscriminatory and three discriminatory probes for each selected locus to discriminate and quantify three homoeolog-differentiating variation types (homoeolog-types) in genomic DNA samples for genotype fitting and constructed a F2 population for segregation analyses. We confirmed inter-subgenomic distinctions of three identified homoeolog-types at each of five selected loci by their interspecific differentiations among 14 species in Ipomoea section batatas and genotyped the loci in 549 F2 lines, selected F1 progenies, and their founding parents. Segregation and genotype analyses revealed a locus-dependent mixed inheritance (disomic, polysomic, and intermediate types) of the homoeolog-types at 4 loci in the F2 population, displaying estimated disomic-inheritance frequencies of 0, 2.72%, 14.52%, and 36.92%, and probably in the F1 population too. There were also low-frequency non-hexaploid F1 and F2 genotypes that were probably derived from double-reduction recombination or partially unreduced gametes, and F2 genotypes of apparent aneuploids/dysploids with neopolyploid-like frequencies. Additional analyses of homoeolog-type genotypes at the 5 loci in 46 lines from various regions revealed locus-dependent selection biases, favoring genotypes having more of one homoeolog-type, i.e. more of di- or homogenized homoeolog-type composition, and one-direction ploidy trending among apparent aneuploids/dysploids. These inheritance features pointed to an evolving segmental allohexaploid sweetpotato impacted by selection biases.
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Affiliation(s)
- Ming Gao
- Cooperative Agricultural Research Center, College of Agriculture, Food and Natural Resources, Prairie View A&M University, Prairie View, TX, United States
| | - Tien Hua
- Cooperative Agricultural Research Center, College of Agriculture, Food and Natural Resources, Prairie View A&M University, Prairie View, TX, United States
| | - Genhua Niu
- AgriLife Research and Extension Center at Dallas, Texas A&M University, Dallas, TX, United States
| | - Joe Masabni
- AgriLife Research and Extension Center at Dallas, Texas A&M University, Dallas, TX, United States
| | - Willie Dewalt
- Cooperative Agricultural Research Center, College of Agriculture, Food and Natural Resources, Prairie View A&M University, Prairie View, TX, United States
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2
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Stoeckel S, Becheler R, Bocharova E, Barloy D. GenAPoPop 1.0: A user-friendly software to analyse genetic diversity and structure from partially clonal and selfed autopolyploid organisms. Mol Ecol Resour 2024; 24:e13886. [PMID: 37902131 DOI: 10.1111/1755-0998.13886] [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] [Received: 11/23/2022] [Revised: 10/05/2023] [Accepted: 10/16/2023] [Indexed: 10/31/2023]
Abstract
Autopolyploidy is quite common in most clades of eukaryotes. The emergence of sequence-based genotyping methods with individual and marker tags now enables confident allele dosage, overcoming the main obstacle to the democratization of the population genetic approaches when studying ecology and evolution of autopolyploid populations and species. Reproductive modes, including clonality, selfing and allogamy, have deep consequences on the ecology and evolution of population and species. Analysing genetic diversity and its dynamics over generations is one efficient way to infer the relative importance of clonality, selfing and allogamy in populations. GenAPoPop is a user-friendly solution to compute the specific corpus of population genetic indices, including indices about genotypic diversity, needed to analyse partially clonal, selfed and allogamous polysomic populations genotyped with confident allele dosage. It also easily provides the posterior probabilities of quantitative reproductive modes in autopolyploid populations genotyped at two-time steps and a graphical representation of the minimum spanning trees of the genetic distances between polyploid individuals, facilitating the interpretation of the genetic coancestry between individuals in hierarchically structured populations. GenAPoPop complements the previously existing solutions, including SPAGEDI and POLYGENE, to use genotypings to study the ecology and evolution of autopolyploid populations. It was specially developed with a simple graphical interface and workflow, and comes with a simulator to facilitate practical courses and teaching of population genetics for autopolyploid populations.
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Affiliation(s)
- Solenn Stoeckel
- IGEPP, INRAE, Institut Agro, Université de Rennes, Le Rheu, France
- DECOD (Ecosystem Dynamics and Sustainability), Institut Agro, IFREMER, INRAE, Rennes, France
| | - Ronan Becheler
- IGEPP, INRAE, Institut Agro, Université de Rennes, Le Rheu, France
- DECOD (Ecosystem Dynamics and Sustainability), Institut Agro, IFREMER, INRAE, Rennes, France
| | - Ekaterina Bocharova
- Evolutionary Developmental Biology laboratory, Koltzov Institute of Developmental Biology of Russian Academy of Sciences (IDB RAS), Moscow, Russia
| | - Dominique Barloy
- DECOD (Ecosystem Dynamics and Sustainability), Institut Agro, IFREMER, INRAE, Rennes, France
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3
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Gerard D. Bayesian tests for random mating in polyploids. Mol Ecol Resour 2023; 23:1812-1822. [PMID: 37578636 DOI: 10.1111/1755-0998.13856] [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] [Received: 09/02/2022] [Revised: 07/24/2023] [Accepted: 08/03/2023] [Indexed: 08/15/2023]
Abstract
Hardy-Weinberg proportions (HWP) are often explored to evaluate the assumption of random mating. However, in autopolyploids, organisms with more than two sets of homologous chromosomes, HWP and random mating are different hypotheses that require different statistical testing approaches. Currently, the only available methods to test for random mating in autopolyploids (i) heavily rely on asymptotic approximations and (ii) assume genotypes are known, ignoring genotype uncertainty. Furthermore, these approaches are all frequentist, and so do not carry the benefits of Bayesian analysis, including ease of interpretability, incorporation of prior information, and consistency under the null. Here, we present Bayesian approaches to test for random mating, bringing the benefits of Bayesian analysis to this problem. Our Bayesian methods also (i) do not rely on asymptotic approximations, being appropriate for small sample sizes, and (ii) optionally account for genotype uncertainty via genotype likelihoods. We validate our methods in simulations and demonstrate on two real datasets how testing for random mating is more useful for detecting genotyping errors than testing for HWP (in a natural population) and testing for Mendelian segregation (in an experimental S1 population). Our methods are implemented in Version 2.0.2 of the hwep R package on the Comprehensive R Archive Network https://cran.r-project.org/package=hwep.
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Affiliation(s)
- David Gerard
- Department of Mathematics and Statistics, American University, Washington DC, USA
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4
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Gerard D. Double reduction estimation and equilibrium tests in natural autopolyploid populations. Biometrics 2023; 79:2143-2156. [PMID: 35848417 DOI: 10.1111/biom.13722] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Accepted: 07/11/2022] [Indexed: 11/27/2022]
Abstract
Many bioinformatics pipelines include tests for equilibrium. Tests for diploids are well studied and widely available, but extending these approaches to autopolyploids is hampered by the presence of double reduction, the comigration of sister chromatid segments into the same gamete during meiosis. Though a hindrance for equilibrium tests, double reduction rates are quantities of interest in their own right, as they provide insights about the meiotic behavior of autopolyploid organisms. Here, we develop procedures to (i) test for equilibrium while accounting for double reduction, and (ii) estimate the double reduction rate given equilibrium. To do so, we take two approaches: a likelihood approach, and a novel U-statistic minimization approach that we show generalizes the classical equilibrium χ2 test in diploids. For small sample sizes and uncertain genotypes, we further develop a bootstrap procedure based on our U-statistic to test for equilibrium. We validate our methods on both simulated and real data.
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Affiliation(s)
- David Gerard
- Department of Mathematics and Statistics, American University, Washington, District of Columbia, USA
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5
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Huang K, Li W, Yang B, Wang D, He S, Shen Y, Ao J, Li Y, Cui Y, Kong Y, Li W, Li N, Dunn DW, Li B. vcfpop: Performing population genetics analyses for autopolyploids and aneuploids based on next-generation sequencing data sets. Mol Ecol Resour 2022. [PMID: 36458971 DOI: 10.1111/1755-0998.13744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 11/28/2022] [Accepted: 11/30/2022] [Indexed: 12/05/2022]
Abstract
Polyploids are cells or organisms with a genome consisting of more than two sets of homologous chromosomes. Polyploid plants have important traits that facilitate speciation and are thus often model systems for evolutionary, molecular ecology and agricultural studies. However, due to their unusual mode of inheritance and double-reduction, diploid models of population genetic analysis cannot properly be applied to autopolyploids. To overcome this problem, we developed a software package entitled vcfpop to perform a variety of population genetic analyses for autopolyploids, such as parentage analysis, analysis of molecular variance, principal coordinates analysis, hierarchical clustering analysis and Bayesian clustering. We used three data sets to evaluate the capability of vcfpop to analyse large data sets on a desktop computer. This software is freely available at http://github.com/huangkang1987/vcfpop.
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Affiliation(s)
- Kang Huang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, British Columbia, Canada
| | - Wenkai Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Bing Yang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Dan Wang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Shujun He
- Shaanxi Key Laboratory for Animal Conservation, Institute of Zoology, Shaanxi Academy of Sciences, Xi'an, China
| | - Yujia Shen
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Jincuo Ao
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Yuhang Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Yunxia Cui
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Yuchen Kong
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Wei Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Nianlong Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Derek W Dunn
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
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6
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Gerard D. Comment on three papers about Hardy–Weinberg equilibrium tests in autopolyploids. Front Genet 2022; 13:1027209. [PMID: 36267399 PMCID: PMC9576855 DOI: 10.3389/fgene.2022.1027209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Accepted: 09/12/2022] [Indexed: 12/04/2022] Open
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7
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Recursive Test of Hardy-Weinberg Equilibrium in Tetraploids. Trends Genet 2021; 37:504-513. [DOI: 10.1016/j.tig.2020.11.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/15/2020] [Accepted: 11/17/2020] [Indexed: 02/08/2023]
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8
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The recombination landscape and multiple QTL mapping in a Solanum tuberosum cv. 'Atlantic'-derived F 1 population. Heredity (Edinb) 2021; 126:817-830. [PMID: 33753876 PMCID: PMC8102480 DOI: 10.1038/s41437-021-00416-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 02/02/2021] [Accepted: 02/04/2021] [Indexed: 02/01/2023] Open
Abstract
There are many challenges involved with the genetic analyses of autopolyploid species, such as the tetraploid potato, Solanum tuberosum (2n = 4x = 48). The development of new analytical methods has made it valuable to re-analyze an F1 population (n = 156) derived from a cross involving 'Atlantic', a widely grown chipping variety in the USA. A fully integrated genetic map with 4285 single nucleotide polymorphisms, spanning 1630 cM, was constructed with MAPpoly software. We observed that bivalent configurations were the most abundant ones (51.0~72.4% depending on parent and linkage group), though multivalent configurations were also observed (2.2~39.2%). Seven traits were evaluated over four years (2006-8 and 2014) and quantitative trait loci (QTL) mapping was carried out using QTLpoly software. Based on a multiple-QTL model approach, we detected 21 QTL for 15 out of 27 trait-year combination phenotypes. A hotspot on linkage group 5 was identified with co-located QTL for maturity, plant yield, specific gravity, and internal heat necrosis resistance evaluated over different years. Additional QTL for specific gravity and dry matter were detected with maturity-corrected phenotypes. Among the genes around QTL peaks, we found those on chromosome 5 that have been previously implicated in maturity (StCDF1) and tuber formation (POTH1). These analyses have the potential to provide insights into the biology and breeding of tetraploid potato and other autopolyploid species.
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9
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Huang K, Huber G, Ritland K, Dunn DW, Li B. Performing parentage analysis for polysomic inheritances based on allelic phenotypes. G3-GENES GENOMES GENETICS 2021; 11:6080682. [PMID: 33585871 PMCID: PMC8022955 DOI: 10.1093/g3journal/jkaa064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 11/09/2020] [Indexed: 11/26/2022]
Abstract
Polyploidy poses several problems for parentage analysis. We present a new polysomic inheritance model for parentage analysis based on genotypes or allelic phenotypes to solve these problems. The effects of five factors are simultaneously accommodated in this model: (1) double-reduction, (2) null alleles, (3) negative amplification, (4) genotyping errors and (5) self-fertilization. To solve genotyping ambiguity (unknown allele dosage), we developed a new method to establish the likelihood formulas for allelic phenotype data and to simultaneously include the effects of our five chosen factors. We then evaluated and compared the performance of our new method with three established methods by using both simulated data and empirical data from the cultivated blueberry (Vaccinium corymbosum). We also developed and compared the performance of two additional estimators to estimate the genotyping error rate and the sample rate. We make our new methods freely available in the software package polygene, at http://github.com/huangkang1987/polygene.
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Affiliation(s)
- Kang Huang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an 710069, China.,Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T1Z4, Canada
| | - Gwendolyn Huber
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T1Z4, Canada
| | - Kermit Ritland
- Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, BC V6T1Z4, Canada
| | - Derek W Dunn
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an 710069, China
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an 710069, China.,Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
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10
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Xiong Z, Gaeta RT, Edger PP, Cao Y, Zhao K, Zhang S, Pires JC. Chromosome inheritance and meiotic stability in allopolyploid Brassica napus. G3-GENES GENOMES GENETICS 2021; 11:6044140. [PMID: 33704431 PMCID: PMC8022990 DOI: 10.1093/g3journal/jkaa011] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Accepted: 11/05/2020] [Indexed: 12/23/2022]
Abstract
Homoeologous recombination, aneuploidy, and other genetic changes are common in resynthesized allopolyploid Brassica napus. In contrast, the chromosomes of cultivars have long been considered to be meiotically stable. To gain a better understanding of the underlying mechanisms leading to stabilization in the allopolyploid, the behavior of chromosomes during meiosis can be compared by unambiguous chromosome identification between resynthesized and natural B. napus. Compared with natural B. napus, resynthesized lines show high rates of nonhomologous centromere association, homoeologous recombination leading to translocation, homoeologous chromosome replacement, and association and breakage of 45S rDNA loci. In both natural and resynthesized B. napus, we observed low rates of univalents, A–C bivalents, and early sister chromatid separations. Reciprocal homoeologous chromosome exchanges and double reductions were photographed for the first time in meiotic telophase I. Meiotic errors were non-uniformly distributed across the genome in resynthesized B. napus, and in particular homoeologs sharing synteny along their entire length exhibited multivalents at diakinesis and polysomic inheritance at telophase I. Natural B. napus appeared to resolve meiotic errors mainly by suppressing homoeologous pairing, resolving nonhomologous centromere associations and 45S rDNA associations before diakinesis, and reducing homoeologous cross-overs.
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Affiliation(s)
- Zhiyong Xiong
- Key Laboratory of Herbage and Endemic Crop Biotechnology, Ministry of Education, College of Life Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021, PR China.,Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
| | - Robert T Gaeta
- Bayer's Crop Science Division, Chesterfield, MO 63017, USA
| | - Patrick P Edger
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA.,Department of Horticulture, Michigan State University, East Lansing, MI 48823, USA
| | - Yao Cao
- Key Laboratory of Herbage and Endemic Crop Biotechnology, Ministry of Education, College of Life Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021, PR China
| | - Kanglu Zhao
- Key Laboratory of Herbage and Endemic Crop Biotechnology, Ministry of Education, College of Life Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021, PR China
| | - Siqi Zhang
- Key Laboratory of Herbage and Endemic Crop Biotechnology, Ministry of Education, College of Life Science, Inner Mongolia University, Hohhot, Inner Mongolia 010021, PR China
| | - J Chris Pires
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211, USA
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11
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Wang C, Ma X, Tang L. Isolation and characterization of twelve polymorphic microsatellite markers in the endangered Hopea hainanensis (Dipterocarpaceae). Ecol Evol 2021; 11:4-10. [PMID: 33437410 PMCID: PMC7790650 DOI: 10.1002/ece3.7077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 11/02/2020] [Accepted: 11/10/2020] [Indexed: 12/22/2022] Open
Abstract
Microsatellite markers were isolated and characterized for Hopea hainanensis Merrill & Chun, an endangered tree species with scattered distribution in Hainan Island and northern Vietnam. Twenty-six microsatellite markers were developed based on next-generation sequencing data and were genotyped by capillary electrophoresis on an ABI 3730xl DNA Analyzer. Twelve markers were found to be polymorphic in H. hainanensis. GENODIVE analyses indicated that the number of alleles ranged from 2 to 6 per locus, and the observed and expected heterozygosity varied from 0 to 0.755 and from 0.259 to 0.779, respectively. Primer transferability was tested with Hopea chinensis Hand.-Mazz. and Hopea reticulata Tardieu, in which 3 and 7 microsatellite markers were found to be polymorphic, separately. The results showed that H. reticulata and H. hainanensis had similar levels of genetic diversity. A neighbor joining dendrogram clustered all individuals into two major groups, one of which was exclusively constituted by H. hainanensis, while the other consisted of two subgroups, corresponding to H. reticulata and H. chinensis, respectively. The 12 polymorphic microsatellite markers could be applied to study genetic diversity, population differentiation, mating system, and fine-scale spatial genetic structures of H. hainanensis as well as its close relatives, facilitating the conservation and restoration of these endangered but valuable Hopea species.
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Affiliation(s)
- Chen Wang
- Key Laboratory of Tropical Biological Resources of Ministry of EducationSchool of Life and Pharmaceutical SciencesHainan UniversityHaikouChina
| | - Xiang Ma
- Key Laboratory of Tropical Biological Resources of Ministry of EducationSchool of Life and Pharmaceutical SciencesHainan UniversityHaikouChina
| | - Liang Tang
- College of Ecology and EnvironmentHainan UniversityHaikouChina
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12
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Wang C, Ma X, Ren M, Tang L. Genetic diversity and population structure in the endangered tree Hopea hainanensis (Dipterocarpaceae) on Hainan Island, China. PLoS One 2020; 15:e0241452. [PMID: 33253236 PMCID: PMC7703895 DOI: 10.1371/journal.pone.0241452] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 10/15/2020] [Indexed: 11/29/2022] Open
Abstract
Hopea hainanensis Merrill & Chun (Dipterocarpaceae) is an endangered tree species restricted to Hainan Island, China and a small part of Northern Vietnam. On Hainan Island, it is an important indicator species for tropical forests. However, because of its highly valued timber, H. hainanensis has suffered from overexploitation, leading to a sharp population decline. To facilitate the conservation of this species, genetic diversity and population structure were assessed using 12 SSR markers for 10 populations sampled across Hainan Island. Compared to non-threatened Hopea species, H. hainanensis exhibited reduced overall genetic diversity and increased population differentiation (AMOVA: FST = 0.23). Bayesian model-based clustering and principal coordinate analysis consistently assigned H. hainanensis individuals into three genetic groups, which were found to be widespread and overlapping geographically. A Mantel test found no correlation between genetic and geographical distances (r = 0.040, p = 0.418). The observed genetic structure suggests that long-distance gene flow occurred among H. hainanensis populations prior to habitat fragmentation. A recent population bottleneck was revealed, which may cause rapid loss of genetic diversity and increased differentiation across populations. Based on these findings, appropriate strategies for the long-term conservation of the endangered species H. hainanensis are proposed.
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Affiliation(s)
- Chen Wang
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Life and Pharmaceutical Sciences, Hainan University, Haikou, China
| | - Xiang Ma
- Key Laboratory of Tropical Biological Resources of Ministry of Education, School of Life and Pharmaceutical Sciences, Hainan University, Haikou, China
| | - Mingxun Ren
- College of Ecology and Environment, Hainan University, Haikou, China
| | - Liang Tang
- College of Ecology and Environment, Hainan University, Haikou, China
- * E-mail:
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13
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Huang K, Wang T, Dunn DW, Zhang P, Sun H, Li B. A generalized framework for AMOVA with multiple hierarchies and ploidies. Integr Zool 2020; 16:33-52. [PMID: 32648364 DOI: 10.1111/1749-4877.12460] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The analysis of molecular variance (AMOVA) is a widely used statistical method in population genetics and molecular ecology. The classic framework of AMOVA only supports haploid and diploid data, in which the number of hierarchies ranges from two to four. In practice, natural populations can be classified into more hierarchies, and polyploidy is frequently observed in extant species. The ploidy level may even vary within the same species, and/or within the same individual. We generalized the framework of AMOVA such that it can be used for any number of hierarchies and any level of ploidy. Based on this framework, we present four methods to account for data that are multilocus genotypic and allelic phenotypic (with unknown allele dosage). We use simulated datasets and an empirical dataset to evaluate the performance of our framework. We make freely available our methods in a new software package, polygene, which is freely available at https://github.com/huangkang1987/polygene.
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Affiliation(s)
- Kang Huang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China.,Department of Forest and Conservation Sciences, University of British Columbia, Vancouver, Canada
| | - Tiantian Wang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Derek W Dunn
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Pei Zhang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Hongjuan Sun
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences, Northwest University, Xi'an, China.,Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China
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14
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Deo TG, Ferreira RCU, Lara LAC, Moraes ACL, Alves-Pereira A, de Oliveira FA, Garcia AAF, Santos MF, Jank L, de Souza AP. High-Resolution Linkage Map With Allele Dosage Allows the Identification of Regions Governing Complex Traits and Apospory in Guinea Grass ( Megathyrsus maximus). FRONTIERS IN PLANT SCIENCE 2020; 11:15. [PMID: 32161603 PMCID: PMC7054243 DOI: 10.3389/fpls.2020.00015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 01/08/2020] [Indexed: 05/11/2023]
Abstract
Forage grasses are mainly used in animal feed to fatten cattle and dairy herds, and guinea grass (Megathyrsus maximus) is considered one of the most productive of the tropical forage crops that reproduce by seeds. Due to the recent process of domestication, this species has several genomic complexities, such as autotetraploidy and aposporous apomixis. Consequently, approaches that relate phenotypic and genotypic data are incipient. In this context, we built a linkage map with allele dosage and generated novel information of the genetic architecture of traits that are important for the breeding of M. maximus. From a full-sib progeny, a linkage map containing 858 single nucleotide polymorphism (SNP) markers with allele dosage information expected for an autotetraploid was obtained. The high genetic variability of the progeny allowed us to map 10 quantitative trait loci (QTLs) related to agronomic traits, such as regrowth capacity and total dry matter, and 36 QTLs related to nutritional quality, which were distributed among all homology groups (HGs). Various overlapping regions associated with the quantitative traits suggested QTL hotspots. In addition, we were able to map one locus that controls apospory (apo-locus) in HG II. A total of 55 different gene families involved in cellular metabolism and plant growth were identified from markers adjacent to the QTLs and APOSPORY locus using the Panicum virgatum genome as a reference in comparisons with the genomes of Arabidopsis thaliana and Oryza sativa. Our results provide a better understanding of the genetic basis of reproduction by apomixis and traits important for breeding programs that considerably influence animal productivity as well as the quality of meat and milk.
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Affiliation(s)
- Thamiris G. Deo
- Center for Molecular Biology and Genetic Engineering, University of Campinas, Campinas, Brazil
| | - Rebecca C. U. Ferreira
- Center for Molecular Biology and Genetic Engineering, University of Campinas, Campinas, Brazil
| | - Letícia A. C. Lara
- Genetics Department, Escola Superior de Agricultura “Luiz de Queiroz,” University of São Paulo, Piracicaba, Brazil
| | - Aline C. L. Moraes
- Plant Biology Department, Biology Institute, University of Campinas, Campinas, Brazil
| | | | - Fernanda A. de Oliveira
- Center for Molecular Biology and Genetic Engineering, University of Campinas, Campinas, Brazil
| | - Antonio A. F. Garcia
- Genetics Department, Escola Superior de Agricultura “Luiz de Queiroz,” University of São Paulo, Piracicaba, Brazil
| | - Mateus F. Santos
- Embrapa Beef Cattle, Brazilian Agricultural Research Corporation, Campo Grande, Brazil
| | - Liana Jank
- Embrapa Beef Cattle, Brazilian Agricultural Research Corporation, Campo Grande, Brazil
| | - Anete P. de Souza
- Center for Molecular Biology and Genetic Engineering, University of Campinas, Campinas, Brazil
- Plant Biology Department, Biology Institute, University of Campinas, Campinas, Brazil
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15
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Huang K, Dunn DW, Ritland K, Li B. polygene: Population genetics analyses for autopolyploids based on allelic phenotypes. Methods Ecol Evol 2019. [DOI: 10.1111/2041-210x.13338] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Affiliation(s)
- Kang Huang
- Shaanxi Key Laboratory for Animal Conservation College of Life Sciences Northwest University Xi’an China
- Department of Forest and Conservation Sciences University of British Columbia Vancouver Canada
| | - Derek W. Dunn
- Shaanxi Key Laboratory for Animal Conservation College of Life Sciences Northwest University Xi’an China
| | - Kermit Ritland
- Department of Forest and Conservation Sciences University of British Columbia Vancouver Canada
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation College of Life Sciences Northwest University Xi’an China
- Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences Kunming China
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16
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Huang K, Dunn DW, Li Z, Zhang P, Dai Y, Li B. Inference of individual ploidy level using codominant markers. Mol Ecol Resour 2019; 19:1218-1229. [DOI: 10.1111/1755-0998.13032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 04/18/2019] [Accepted: 05/01/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Kang Huang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Derek W. Dunn
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Zhonghu Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Pei Zhang
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Yu Dai
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal Conservation, College of Life Sciences Northwest University Xi'an China
- Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sciences Kunming China
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17
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Mi R, Wang T, Dunn DW, Huang K, Li B. Development of simple sequence repeat markers for Chamerion angustifolium (Onagraceae). APPLICATIONS IN PLANT SCIENCES 2019; 7:e01244. [PMID: 31139510 PMCID: PMC6526638 DOI: 10.1002/aps3.1244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 12/02/2018] [Accepted: 01/09/2019] [Indexed: 06/09/2023]
Abstract
PREMISE Rosebay willowherb, or fireweed (Chamerion angustifolium: Onagraceae), has diploid, tetraploid, and hexaploid cytotypes. There are known physiological and ecological differences among the three cytotypes, but genetic differences remain undetermined. We developed simple sequence repeat (SSR) markers for this species. METHODS AND RESULTS Leaf samples were collected from three hexaploid C. angustifolium populations. We successfully amplified 16 SSR loci, which were found to be highly polymorphic. The number of alleles, the observed heterozygosity levels, and the expected heterozygosity levels ranged from four to 13, 0.286-0.899, and 0.372-0.871, respectively. Most primers could also be amplified successfully in C. conspersum and the closely related species Epilobium palustre. CONCLUSIONS The 16 polymorphic SSR markers developed here will be useful for genetic studies in C. angustifolium and related species.
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Affiliation(s)
- Rui Mi
- Shaanxi Key Laboratory for Animal ConservationCollege of Life SciencesNorthwest UniversityXi'an710069People's Republic of China
| | - Tongcheng Wang
- Shaanxi Key Laboratory for Animal ConservationCollege of Life SciencesNorthwest UniversityXi'an710069People's Republic of China
| | - Derek W. Dunn
- Shaanxi Key Laboratory for Animal ConservationCollege of Life SciencesNorthwest UniversityXi'an710069People's Republic of China
| | - Kang Huang
- Shaanxi Key Laboratory for Animal ConservationCollege of Life SciencesNorthwest UniversityXi'an710069People's Republic of China
| | - Baoguo Li
- Shaanxi Key Laboratory for Animal ConservationCollege of Life SciencesNorthwest UniversityXi'an710069People's Republic of China
- Center for Excellence in Animal Evolution and GeneticsChinese Academy of SciencesKunming650223People's Republic of China
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