1
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Burda K, Konczal M. Validation of machine learning approach for direct mutation rate estimation. Mol Ecol Resour 2023; 23:1757-1771. [PMID: 37486035 DOI: 10.1111/1755-0998.13841] [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: 02/25/2023] [Revised: 06/16/2023] [Accepted: 07/05/2023] [Indexed: 07/25/2023]
Abstract
Mutations are the primary source of all genetic variation. Knowledge about their rates is critical for any evolutionary genetic analyses, but for a long time, that knowledge has remained elusive and indirectly inferred. In recent years, parent-offspring comparisons have yielded the first direct mutation rate estimates. The analyses are, however, challenging due to high rate of false positives and no consensus regarding standardized filtering of candidate de novo mutations. Here, we validate the application of a machine learning approach for such a task and estimate the mutation rate for the guppy (Poecilia reticulata), a model species in eco-evolutionary studies. We sequenced 4 parents and 20 offspring, followed by screening their genomes for de novo mutations. The initial large number of candidate de novo mutations was hard-filtered to remove false-positive results. These results were compared with mutation rate estimated with a supervised machine learning approach. Both approaches were followed by molecular validation of all candidate de novo mutations and yielded similar results. The ML method uniquely identified three mutations, but overall required more hands-on curation and had higher rates of false positives and false negatives. Both methods concordantly showed no difference in mutation rates between families. Estimated here the guppy mutation rate is among the lowest directly estimated mutation rates in vertebrates; however, previous research has also found low estimated rates in other teleost fishes. We discuss potential explanations for such a pattern, as well as future utility and limitations of machine learning approaches.
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Affiliation(s)
- Katarzyna Burda
- Evolutionary Biology Group, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
| | - Mateusz Konczal
- Evolutionary Biology Group, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
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2
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Zhang C, Reid K, Sands AF, Fraimout A, Schierup MH, Merilä J. De Novo Mutation Rates in Sticklebacks. Mol Biol Evol 2023; 40:msad192. [PMID: 37648662 PMCID: PMC10503787 DOI: 10.1093/molbev/msad192] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 08/21/2023] [Accepted: 08/24/2023] [Indexed: 09/01/2023] Open
Abstract
Mutation rate is a fundamental parameter in population genetics. Apart from being an important scaling parameter for demographic and phylogenetic inference, it allows one to understand at what rate new genetic diversity is generated and what the expected level of genetic diversity is in a population at equilibrium. However, except for well-established model organisms, accurate estimates of de novo mutation rates are available for a very limited number of organisms from the wild. We estimated mutation rates (µ) in two marine populations of the nine-spined stickleback (Pungitius pungitius) with the aid of several 2- and 3-generational family pedigrees, deep (>50×) whole-genome resequences and a high-quality reference genome. After stringent filtering, we discovered 308 germline mutations in 106 offspring translating to µ = 4.83 × 10-9 and µ = 4.29 × 10-9 per base per generation in the two populations, respectively. Up to 20% of the mutations were shared by full-sibs showing that the level of parental mosaicism was relatively high. Since the estimated µ was 3.1 times smaller than the commonly used substitution rate, recalibration with µ led to substantial increase in estimated divergence times between different stickleback species. Our estimates of the de novo mutation rate should provide a useful resource for research focused on fish population genetics and that of sticklebacks in particular.
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Affiliation(s)
- Chaowei Zhang
- Area of Ecology & Biodiversity, School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR
| | - Kerry Reid
- Area of Ecology & Biodiversity, School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR
| | - Arthur F Sands
- Area of Ecology & Biodiversity, School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR
| | - Antoine Fraimout
- Area of Ecology & Biodiversity, School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR
- Research Program in Organismal & Evolutionary Biology, Faculty Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | | | - Juha Merilä
- Area of Ecology & Biodiversity, School of Biological Sciences, The University of Hong Kong, Hong Kong, Hong Kong SAR
- Research Program in Organismal & Evolutionary Biology, Faculty Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
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3
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Lin Y, Darolti I, van der Bijl W, Morris J, Mank JE. Extensive variation in germline de novo mutations in Poecilia reticulata. Genome Res 2023; 33:1317-1324. [PMID: 37442578 PMCID: PMC10547258 DOI: 10.1101/gr.277936.123] [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: 03/30/2023] [Accepted: 07/07/2023] [Indexed: 07/15/2023]
Abstract
The rate of germline mutation is fundamental to evolutionary processes, as it generates the variation upon which selection acts. The guppy, Poecilia reticulata, is a model of rapid adaptation, however the relative contribution of standing genetic variation versus de novo mutation (DNM) to evolution in this species remains unclear. Here, we use pedigree-based approaches to quantify and characterize germline DNMs in three large guppy families. Our results suggest germline mutation rate in the guppy varies substantially across individuals and families. Most DNMs are shared across multiple siblings, suggesting they arose during early embryonic development. DNMs are randomly distributed throughout the genome, and male-biased mutation rate is low, as would be expected from the short guppy generation time. Overall, our study shows remarkable variation in germline mutation rate and provides insights into rapid evolution of guppies.
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Affiliation(s)
- Yuying Lin
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada;
| | - Iulia Darolti
- Department of Ecology and Evolution, University of Lausanne, CH-1015 Lausanne, Switzerland
| | - Wouter van der Bijl
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Jake Morris
- School of Biological Science, University of Bristol, Bristol BS8 1TQ, United Kingdom
| | - Judith E Mank
- Department of Zoology and Biodiversity Research Centre, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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4
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Krasovec M, Hoshino M, Zheng M, Lipinska AP, Coelho SM. Low Spontaneous Mutation Rate in Complex Multicellular Eukaryotes with a Haploid-Diploid Life Cycle. Mol Biol Evol 2023; 40:msad105. [PMID: 37140022 PMCID: PMC10254074 DOI: 10.1093/molbev/msad105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/22/2023] [Accepted: 05/01/2023] [Indexed: 05/05/2023] Open
Abstract
The spontaneous mutation rate µ is a crucial parameter to understand evolution and biodiversity. Mutation rates are highly variable across species, suggesting that µ is susceptible to selection and drift and that species life cycle and life history may impact its evolution. In particular, asexual reproduction and haploid selection are expected to affect the mutation rate, but very little empirical data are available to test this expectation. Here, we sequence 30 genomes of a parent-offspring pedigree in the model brown alga Ectocarpus sp.7, and 137 genomes of an interspecific cross of the closely related brown alga Scytosiphon to have access to the spontaneous mutation rate of representative organisms of a complex multicellular eukaryotic lineage outside animals and plants, and to evaluate the potential impact of life cycle on the mutation rate. Brown algae alternate between a haploid and a diploid stage, both multicellular and free living, and utilize both sexual and asexual reproduction. They are, therefore, excellent models to empirically test expectations of the effect of asexual reproduction and haploid selection on mutation rate evolution. We estimate that Ectocarpus has a base substitution rate of µbs = 4.07 × 10-10 per site per generation, whereas the Scytosiphon interspecific cross had µbs = 1.22 × 10-9. Overall, our estimations suggest that these brown algae, despite being multicellular complex eukaryotes, have unusually low mutation rates. In Ectocarpus, effective population size (Ne) could not entirely explain the low µbs. We propose that the haploid-diploid life cycle, combined with extensive asexual reproduction, may be additional key drivers of the mutation rate in these organisms.
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Affiliation(s)
- Marc Krasovec
- Sorbonne Université, CNRS, UMR 7232 Biologie Intégrative des Organismes Marins (BIOM), Observatoire Océanologique, Banyuls-sur-Mer, France
| | - Masakazu Hoshino
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Min Zheng
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Agnieszka P Lipinska
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
| | - Susana M Coelho
- Department of Algal Development and Evolution, Max Planck Institute for Biology Tübingen, Tübingen, Germany
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5
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Bergeron LA, Besenbacher S, Zheng J, Li P, Bertelsen MF, Quintard B, Hoffman JI, Li Z, St Leger J, Shao C, Stiller J, Gilbert MTP, Schierup MH, Zhang G. Evolution of the germline mutation rate across vertebrates. Nature 2023; 615:285-291. [PMID: 36859541 PMCID: PMC9995274 DOI: 10.1038/s41586-023-05752-y] [Citation(s) in RCA: 73] [Impact Index Per Article: 73.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/23/2023] [Indexed: 03/03/2023]
Abstract
The germline mutation rate determines the pace of genome evolution and is an evolving parameter itself1. However, little is known about what determines its evolution, as most studies of mutation rates have focused on single species with different methodologies2. Here we quantify germline mutation rates across vertebrates by sequencing and comparing the high-coverage genomes of 151 parent-offspring trios from 68 species of mammals, fishes, birds and reptiles. We show that the per-generation mutation rate varies among species by a factor of 40, with mutation rates being higher for males than for females in mammals and birds, but not in reptiles and fishes. The generation time, age at maturity and species-level fecundity are the key life-history traits affecting this variation among species. Furthermore, species with higher long-term effective population sizes tend to have lower mutation rates per generation, providing support for the drift barrier hypothesis3. The exceptionally high yearly mutation rates of domesticated animals, which have been continually selected on fecundity traits including shorter generation times, further support the importance of generation time in the evolution of mutation rates. Overall, our comparative analysis of pedigree-based mutation rates provides ecological insights on the mutation rate evolution in vertebrates.
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Affiliation(s)
- Lucie A Bergeron
- Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
| | - Søren Besenbacher
- Department of Molecular Medicine, Aarhus University, Aarhus, Denmark
| | - Jiao Zheng
- BGI-Shenzhen, Shenzhen, China
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen, China
| | | | | | | | - Joseph I Hoffman
- Department of Animal Behaviour, Bielefeld University, Bielefeld, Germany
- British Antarctic Survey, High Cross, Cambridge, UK
| | - Zhipeng Li
- College of Animal Science and Technology, Jilin Agricultural University, Changchun, China
| | - Judy St Leger
- Department of Biomedical Sciences, Cornell University, Ithaca, NY, USA
| | - Changwei Shao
- Key Lab of Sustainable Development of Marine Fisheries, Ministry of Agriculture and Rural Affairs, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, China
| | - Josefin Stiller
- Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - M Thomas P Gilbert
- Center for Evolutionary Hologenomics, The GLOBE Institute, University of Copenhagen, Copenhagen, Denmark
- University Museum, NTNU, Trondheim, Norway
| | | | - Guojie Zhang
- Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark.
- Centre for Evolutionary & Organismal Biology, Women's Hospital, Zhejiang University School of Medicine, Hangzhou, China.
- Liangzhu Laboratory, Zhejiang University Medical Center, Hangzhou, China.
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.
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6
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Armstrong EE, Campana MG. RatesTools: a Nextflow pipeline for detecting de novo germline mutations in pedigree sequence data. BIOINFORMATICS (OXFORD, ENGLAND) 2023; 39:6873736. [PMID: 36469327 DOI: 10.1093/bioinformatics/btac784] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 10/12/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022]
Abstract
SUMMARY Here, we introduce RatesTools, an automated pipeline to infer de novo mutation rates from parent-offspring trio data of diploid organisms. By providing a reference genome and high-coverage, whole-genome resequencing data of a minimum of three individuals (sire, dam and offspring), RatesTools provides a list of candidate de novo mutations and calculates a putative mutation rate. RatesTools uses several quality filtering steps, such as discarding sites with low mappability and highly repetitive regions, as well as sites with low genotype and mapping qualities to find potential de novo mutations. In addition, RatesTools implements several optional filters based on post hoc assumptions of the heterozygosity and mutation rate of the organism. Filters are highly customizable to user specifications in order to maximize utility across a wide range of applications. AVAILABILITY AND IMPLEMENTATION RatesTools is freely available at https://github.com/campanam/RatesTools under a Creative Commons Zero (CC0) license. The pipeline is implemented in Nextflow (Di Tommaso et al., 2017), Ruby (http://www.ruby-lang.org), Bash (https://www.gnu.org/software/bash/) and R (R Core Team, 2020) with reliance upon several other freely available tools. RatesTools is compatible with macOS and Linux operating systems. SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Ellie E Armstrong
- School of Biological Sciences, Washington State University, Pullman, WA 99164, USA.,Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Michael G Campana
- Center for Conservation Genomics, Smithsonian's National Zoo and Conservation Biology Institute, Washington, DC 20008, USA
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7
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Pozzi L, Penna A. Rocks and clocks revised: New promises and challenges in dating the primate tree of life. Evol Anthropol 2022; 31:138-153. [PMID: 35102633 DOI: 10.1002/evan.21940] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 10/04/2021] [Accepted: 01/12/2022] [Indexed: 01/14/2023]
Abstract
In recent years, multiple technological and methodological advances have increased our ability to estimate phylogenies, leading to more accurate dating of the primate tree of life. Here we provide an overview of the limitations and potentials of some of these advancements and discuss how dated phylogenies provide the crucial temporal scale required to understand primate evolution. First, we review new methods, such as the total-evidence dating approach, that promise a better integration between the fossil record and molecular data. We then explore how the ever-increasing availability of genomic-level data for more primate species can impact our ability to accurately estimate timetrees. Finally, we discuss more recent applications of mutation rates to date divergence times. We highlight example studies that have applied these approaches to estimate divergence dates within primates. Our goal is to provide a critical overview of these new developments and explore the promises and challenges of their application in evolutionary anthropology.
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Affiliation(s)
- Luca Pozzi
- Department of Anthropology, The University of Texas at San Antonio, San Antonio, Texas, USA
| | - Anna Penna
- Department of Anthropology, The University of Texas at San Antonio, San Antonio, Texas, USA
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8
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Zhang M, Yang Q, Ai H, Huang L. Revisiting the Evolutionary History of Pigs via De Novo Mutation Rate Estimation in A Three-generation Pedigree. GENOMICS, PROTEOMICS & BIOINFORMATICS 2022; 20:1040-1052. [PMID: 35181533 DOI: 10.1016/j.gpb.2022.02.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 12/20/2021] [Accepted: 02/09/2022] [Indexed: 12/30/2022]
Abstract
The mutation rate used in the previous analyses of pig evolution and demographics was cursory and hence invited potential bias in inferring evolutionary history. Herein, we estimated the de novo mutation rate of pigs as 3.6 × 10-9 per base per generation using high-quality whole-genome sequencing data from nine individuals in a three-generation pedigree through stringent filtering and validation. Using this mutation rate, we re-investigated the evolutionary history of pigs. The estimated divergence time of ∼ 10 kiloyears ago (KYA) between European wild and domesticated pigs was consistent with the domestication time of European pigs based on archaeological evidence. However, other divergence events inferred here were not as ancient as previously described. Our estimates suggested that Sus speciation occurred ∼ 1.36 million years ago (MYA); European wild pigs split from Asian wild pigs only ∼ 219 KYA; and south and north Chinese wild pigs split ∼ 25 KYA. Meanwhile, our results showed that the most recent divergence event between Chinese wild and domesticated pigs occurred in the Hetao plain, North China, approximately 20 KYA, supporting the possibly independent domestication in North China along the middle Yellow River. We also found that the maximum effective population size of pigs was ∼ 6 times larger than the previous estimate. An archaic migration from other Sus species originating ∼ 2 MYA to European pigs was detected during western colonization of pigs; this interfered with the previous demographic inference. Our de novo mutation rate estimation and its consequences for demographic history inference reasonably provide a new vision regarding the evolutionary history of pigs.
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Affiliation(s)
- Mingpeng Zhang
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang 330045, China
| | - Qiang Yang
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang 330045, China
| | - Huashui Ai
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang 330045, China.
| | - Lusheng Huang
- State Key Laboratory for Swine Genetic Improvement and Production Technology, Jiangxi Agricultural University, Nanchang 330045, China.
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9
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Bergeron LA, Besenbacher S, Turner T, Versoza CJ, Wang RJ, Price AL, Armstrong E, Riera M, Carlson J, Chen HY, Hahn MW, Harris K, Kleppe AS, López-Nandam EH, Moorjani P, Pfeifer SP, Tiley GP, Yoder AD, Zhang G, Schierup MH. The mutationathon highlights the importance of reaching standardization in estimates of pedigree-based germline mutation rates. eLife 2022; 11:73577. [PMID: 35018888 PMCID: PMC8830884 DOI: 10.7554/elife.73577] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2021] [Accepted: 01/11/2022] [Indexed: 11/13/2022] Open
Abstract
In the past decade, several studies have estimated the human per-generation germline mutation rate using large pedigrees. More recently, estimates for various nonhuman species have been published. However, methodological differences among studies in detecting germline mutations and estimating mutation rates make direct comparisons difficult. Here, we describe the many different steps involved in estimating pedigree-based mutation rates, including sampling, sequencing, mapping, variant calling, filtering, and appropriately accounting for false-positive and false-negative rates. For each step, we review the different methods and parameter choices that have been used in the recent literature. Additionally, we present the results from a ‘Mutationathon,’ a competition organized among five research labs to compare germline mutation rate estimates for a single pedigree of rhesus macaques. We report almost a twofold variation in the final estimated rate among groups using different post-alignment processing, calling, and filtering criteria, and provide details into the sources of variation across studies. Though the difference among estimates is not statistically significant, this discrepancy emphasizes the need for standardized methods in mutation rate estimations and the difficulty in comparing rates from different studies. Finally, this work aims to provide guidelines for computational and statistical benchmarks for future studies interested in identifying germline mutations from pedigrees.
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Affiliation(s)
- Lucie A Bergeron
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Søren Besenbacher
- Department of Molecular Medicine (MOMA), Aarhus University, Aarhus N, Denmark
| | - Tychele Turner
- Department of Genetics, Washington University in St. Louis, Saint Louis, United States
| | - Cyril J Versoza
- Center for Evolution and Medicine, Arizona State University, Tempe, United States
| | - Richard J Wang
- Department of Biology, Indiana University, Bloomington, United States
| | - Alivia Lee Price
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Ellie Armstrong
- Department of Biology, Stanford University, Stanford, United States
| | - Meritxell Riera
- Bioinformatics Research Centre, Aarhus University, Aarhus, Denmark
| | - Jedidiah Carlson
- Department of Genome Sciences, University of Washington, Seattle, United States
| | - Hwei-Yen Chen
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Matthew W Hahn
- Department of Biology, Indiana University, Bloomington, United States
| | - Kelley Harris
- Department of Genome Sciences, University of Washington, Seattle, United States
| | | | | | - Priya Moorjani
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, United States
| | - Susanne P Pfeifer
- School of Life Sciences, Arizona State University, Tempe, United States
| | - George P Tiley
- Department of Biology, Duke University, Durham, United States
| | - Anne D Yoder
- Department of Biology, Duke University, Durham, United States
| | - Guojie Zhang
- Department of Biology, University of Copenhagen, Copenhagen, Denmark
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10
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Rashid I, Campos M, Collier T, Crepeau M, Weakley A, Gripkey H, Lee Y, Schmidt H, Lanzaro GC. Spontaneous mutation rate estimates for the principal malaria vectors Anopheles coluzzii and Anopheles stephensi. Sci Rep 2022; 12:226. [PMID: 34996998 PMCID: PMC8742016 DOI: 10.1038/s41598-021-03943-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Accepted: 12/07/2021] [Indexed: 11/17/2022] Open
Abstract
Using high-depth whole genome sequencing of F0 mating pairs and multiple individual F1 offspring, we estimated the nuclear mutation rate per generation in the malaria vectors Anopheles coluzzii and Anopheles stephensi by detecting de novo genetic mutations. A purpose-built computer program was employed to filter actual mutations from a deep background of superficially similar artifacts resulting from read misalignment. Performance of filtering parameters was determined using software-simulated mutations, and the resulting estimate of false negative rate was used to correct final mutation rate estimates. Spontaneous mutation rates by base substitution were estimated at 1.00 × 10−9 (95% confidence interval, 2.06 × 10−10—2.91 × 10−9) and 1.36 × 10−9 (95% confidence interval, 4.42 × 10−10—3.18 × 10−9) per site per generation in A. coluzzii and A. stephensi respectively. Although similar studies have been performed on other insect species including dipterans, this is the first study to empirically measure mutation rates in the important genus Anopheles, and thus provides an estimate of µ that will be of utility for comparative evolutionary genomics, as well as for population genetic analysis of malaria vector mosquito species.
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Affiliation(s)
- Iliyas Rashid
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, UC Davis, 1089 Veterinary Medicine Dr, 4225 VM3B, Davis, CA, 95616, USA.,Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA, USA.,Tata Institute for Genetics and Society, Center at inStem, Bangalore, Karnataka, 560065, India
| | - Melina Campos
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, UC Davis, 1089 Veterinary Medicine Dr, 4225 VM3B, Davis, CA, 95616, USA
| | - Travis Collier
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, UC Davis, 1089 Veterinary Medicine Dr, 4225 VM3B, Davis, CA, 95616, USA
| | - Marc Crepeau
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, UC Davis, 1089 Veterinary Medicine Dr, 4225 VM3B, Davis, CA, 95616, USA
| | - Allison Weakley
- Department of ChEM-H Operations, Stanford University, 450 Serra Mall, Stanford, CA, 94305, USA
| | - Hans Gripkey
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, UC Davis, 1089 Veterinary Medicine Dr, 4225 VM3B, Davis, CA, 95616, USA
| | - Yoosook Lee
- Florida Medical Entomology Laboratory, University of Florida, 200 9th St SE, Vero Beach, FL, 32962, USA
| | - Hanno Schmidt
- Anthropology, Institute of Organismic and Molecular Evolution (iomE), Johannes Gutenberg University of Mainz, Saarstraße 21, 55122, Mainz, Germany
| | - Gregory C Lanzaro
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, UC Davis, 1089 Veterinary Medicine Dr, 4225 VM3B, Davis, CA, 95616, USA.
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11
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Warmuth VM, Burgess MD, Laaksonen T, Manica A, Mägi M, Nord A, Primmer CR, Sætre GP, Winkel W, Ellegren H. Major population splits coincide with episodes of rapid climate change in a forest-dependent bird. Proc Biol Sci 2021; 288:20211066. [PMID: 34727712 PMCID: PMC8564624 DOI: 10.1098/rspb.2021.1066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 10/07/2021] [Indexed: 11/17/2022] Open
Abstract
Climate change influences population demography by altering patterns of gene flow and reproductive isolation. Direct mutation rates offer the possibility for accurate dating on the within-species level but are currently only available for a handful of vertebrate species. Here, we use the first directly estimated mutation rate in birds to study the evolutionary history of pied flycatchers (Ficedula hypoleuca). Using a combination of demographic inference and species distribution modelling, we show that all major population splits in this forest-dependent system occurred during periods of increased climate instability and rapid global temperature change. We show that the divergent Spanish subspecies originated during the Eemian-Weichselian transition 115-104 thousand years ago (kya), and not during the last glacial maximum (26.5-19 kya), as previously suggested. The magnitude and rates of climate change during the glacial-interglacial transitions that preceded population splits in pied flycatchers were similar to, or exceeded, those predicted to occur in the course of the current, human-induced climate crisis. As such, our results provide a timely reminder of the strong impact that episodes of climate instability and rapid temperature changes can have on species' evolutionary trajectories, with important implications for the natural world in the Anthropocene.
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Affiliation(s)
- Vera M. Warmuth
- Department of Evolutionary Biology, Biozentrum Martinsried, Ludwig-Maximilians Universität München, Planegg-Martinsried, Germany
- Department of Evolutionary Biology, Evolutionary Biology Centre (EBC), Uppsala University, Uppsala, Sweden
| | - Malcolm D. Burgess
- Centre for Animal Behaviour, University of Exeter, Exeter, UK
- RSPB Centre for Conservation Science, Sandy, UK
| | - Toni Laaksonen
- Department of Biology, University of Turku, Turku, Finland
| | - Andrea Manica
- Department of Zoology, University of Cambridge, Cambridge, UK
| | - Marko Mägi
- Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - Andreas Nord
- Department of Biology, Section for Evolutionary Ecology, Lund University, Lund, Sweden
| | - Craig R. Primmer
- Organismal and Evolutionary Biology Research Program, University of Helsinki, Finland
- Institute of Biotechnology, Helsinki Institute of Life Sciences (HiLIFE), University of Helsinki, Finland
| | - Glenn-Peter Sætre
- Centre for Ecological and Evolutionary Synthesis, University of Oslo, Oslo, Norway
| | - Wolfgang Winkel
- Institute of Avian Research, ‘Vogelwarte Helgoland’, Wilhelmshaven, Germany
| | - Hans Ellegren
- Department of Evolutionary Biology, Evolutionary Biology Centre (EBC), Uppsala University, Uppsala, Sweden
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12
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Bergeron LA, Besenbacher S, Schierup MH, Zhang G. Studying mutation rate evolution in primates-a need for systematic comparison of computational pipelines. Gigascience 2021; 10:giab072. [PMID: 34673928 PMCID: PMC8529962 DOI: 10.1093/gigascience/giab072] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 10/04/2021] [Accepted: 10/04/2021] [Indexed: 11/14/2022] Open
Abstract
The lack of consensus methods to estimate germline mutation rates from pedigrees has led to substantial differences in computational pipelines in the published literature. Here, we answer Susanne Pfeifer's opinion piece discussing the pipeline choices of our recent article estimating the germline mutation rate of rhesus macaques (Macaca mulatta). We acknowledge the differences between the method that we applied and the one preferred by Pfeifer. Yet, we advocate for full transparency and justification of choices as long as rigorous comparison of pipelines remains absent because it is the only way to conclude on best practices for the field.
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Affiliation(s)
- Lucie A Bergeron
- Section for Ecology and Evolution, Department of Biology, University of
Copenhagen, 2100, Copenhagen, Denmark
| | - Søren Besenbacher
- Department of Molecular Medicine, Aarhus University, 8200,
Aarhus, Denmark
| | - Mikkel H Schierup
- Bioinformatics Research Centre, Aarhus University, 8000,
Aarhus, Denmark
| | - Guojie Zhang
- Section for Ecology and Evolution, Department of Biology, University of
Copenhagen, 2100, Copenhagen, Denmark
- BGI-Shenzhen, Shenzhen, Guangdong 518083, China
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute
of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of
Sciences, Kunming 650223, China
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13
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Pfeifer SP. Studying mutation rate evolution in primates-the effects of computational pipelines and parameter choices. Gigascience 2021; 10:6407243. [PMID: 34673929 PMCID: PMC8529961 DOI: 10.1093/gigascience/giab069] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Accepted: 09/13/2021] [Indexed: 11/12/2022] Open
Abstract
This commentary investigates the important role of computational pipeline and parameter choices in performing mutation rate estimation, using the recent article published in this journal by Bergeron et al. entitled "The germline mutational process in rhesus macaque and its implications for phylogenetic dating" as an illustrative example.
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Affiliation(s)
- Susanne P Pfeifer
- Correspondence address. Susanne P. Pfeifer, School of Life Sciences, Arizona
State University, Tempe, AZ 85281, USA. E-mail:
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14
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Breton G, Johansson ACV, Sjödin P, Schlebusch CM, Jakobsson M. Comparison of sequencing data processing pipelines and application to underrepresented African human populations. BMC Bioinformatics 2021; 22:488. [PMID: 34627144 PMCID: PMC8502359 DOI: 10.1186/s12859-021-04407-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 09/27/2021] [Indexed: 11/10/2022] Open
Abstract
Background Population genetic studies of humans make increasing use of high-throughput sequencing in order to capture diversity in an unbiased way. There is an abundance of sequencing technologies, bioinformatic tools and the available genomes are increasing in number. Studies have evaluated and compared some of these technologies and tools, such as the Genome Analysis Toolkit (GATK) and its “Best Practices” bioinformatic pipelines. However, studies often focus on a few genomes of Eurasian origin in order to detect technical issues. We instead surveyed the use of the GATK tools and established a pipeline for processing high coverage full genomes from a diverse set of populations, including Sub-Saharan African groups, in order to reveal challenges from human diversity and stratification. Results We surveyed 29 studies using high-throughput sequencing data, and compared their strategies for data pre-processing and variant calling. We found that processing of data is very variable across studies and that the GATK “Best Practices” are seldom followed strictly. We then compared three versions of a GATK pipeline, differing in the inclusion of an indel realignment step and with a modification of the base quality score recalibration step. We applied the pipelines on a diverse set of 28 individuals. We compared the pipelines in terms of count of called variants and overlap of the callsets. We found that the pipelines resulted in similar callsets, in particular after callset filtering. We also ran one of the pipelines on a larger dataset of 179 individuals. We noted that including more individuals at the joint genotyping step resulted in different counts of variants. At the individual level, we observed that the average genome coverage was correlated to the number of variants called. Conclusions We conclude that applying the GATK “Best Practices” pipeline, including their recommended reference datasets, to underrepresented populations does not lead to a decrease in the number of called variants compared to alternative pipelines. We recommend to aim for coverage of > 30X if identifying most variants is important, and to work with large sample sizes at the variant calling stage, also for underrepresented individuals and populations. Supplementary Information The online version contains supplementary material available at 10.1186/s12859-021-04407-x.
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Affiliation(s)
- Gwenna Breton
- Human Evolution, Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18C, 752 36, Uppsala, Sweden.
| | - Anna C V Johansson
- Department of Cell and Molecular Biology, National Bioinformatics Infrastructure Sweden, Science for Life Laboratory, Uppsala University, Husargatan 3, 752 37, Uppsala, Sweden
| | - Per Sjödin
- Human Evolution, Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18C, 752 36, Uppsala, Sweden
| | - Carina M Schlebusch
- Human Evolution, Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18C, 752 36, Uppsala, Sweden.,Palaeo-Research Institute, University of Johannesburg, P.O. Box 524, Auckland Park, 2006, South Africa.,Science for Life Laboratory, Uppsala, Sweden
| | - Mattias Jakobsson
- Human Evolution, Department of Organismal Biology, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18C, 752 36, Uppsala, Sweden. .,Palaeo-Research Institute, University of Johannesburg, P.O. Box 524, Auckland Park, 2006, South Africa. .,Science for Life Laboratory, Uppsala, Sweden.
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15
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Campbell CR, Tiley GP, Poelstra JW, Hunnicutt KE, Larsen PA, Lee HJ, Thorne JL, Dos Reis M, Yoder AD. Pedigree-based and phylogenetic methods support surprising patterns of mutation rate and spectrum in the gray mouse lemur. Heredity (Edinb) 2021; 127:233-244. [PMID: 34272504 PMCID: PMC8322134 DOI: 10.1038/s41437-021-00446-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 05/25/2021] [Accepted: 05/26/2021] [Indexed: 02/06/2023] Open
Abstract
Mutations are the raw material on which evolution acts, and knowledge of their frequency and genomic distribution is crucial for understanding how evolution operates at both long and short timescales. At present, the rate and spectrum of de novo mutations have been directly characterized in relatively few lineages. Our study provides the first direct mutation-rate estimate for a strepsirrhine (i.e., the lemurs and lorises), which comprises nearly half of the primate clade. Using high-coverage linked-read sequencing for a focal quartet of gray mouse lemurs (Microcebus murinus), we estimated the mutation rate to be among the highest calculated for a mammal at 1.52 × 10-8 (95% credible interval: 1.28 × 10-8-1.78 × 10-8) mutations/site/generation. Further, we found an unexpectedly low count of paternal mutations, and only a modest overrepresentation of mutations at CpG sites. Despite the surprising nature of these results, we found both the rate and spectrum to be robust to the manipulation of a wide range of computational filtering criteria. We also sequenced a technical replicate to estimate a false-negative and false-positive rate for our data and show that any point estimate of a de novo mutation rate should be considered with a large degree of uncertainty. For validation, we conducted an independent analysis of context-dependent substitution types for gray mouse lemur and five additional primate species for which de novo mutation rates have also been estimated. These comparisons revealed general consistency of the mutation spectrum between the pedigree-based and the substitution-rate analyses for all species compared.
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Affiliation(s)
- C Ryan Campbell
- Department of Biology, Duke University, Durham, NC, USA
- Department of Evolutionary Anthropology, Duke University, Durham, NC, USA
| | | | | | - Kelsie E Hunnicutt
- Department of Biology, Duke University, Durham, NC, USA
- Department of Biological Sciences, University of Denver, Denver, CO, USA
| | - Peter A Larsen
- Department of Biology, Duke University, Durham, NC, USA
- Department of Veterinary and Biomedical Sciences, University of Minnesota, St. Paul, MN, USA
| | - Hui-Jie Lee
- Department of Biostatistics and Bioinformatics, Duke University, Durham, NC, USA
| | - Jeffrey L Thorne
- Bioinformatics Research Center, North Carolina State University, Raleigh, NC, USA
| | - Mario Dos Reis
- School of Biological and Chemical Sciences, Queen Mary University of London, London, UK
| | - Anne D Yoder
- Department of Biology, Duke University, Durham, NC, USA.
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16
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Yoder AD, Tiley GP. The challenge and promise of estimating the de novo mutation rate from whole-genome comparisons among closely related individuals. Mol Ecol 2021; 30:6087-6100. [PMID: 34062029 DOI: 10.1111/mec.16007] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 04/22/2021] [Accepted: 05/26/2021] [Indexed: 12/20/2022]
Abstract
Germline mutations are the raw material for natural selection, driving species evolution and the generation of earth's biodiversity. Without this driver of genetic diversity, life on earth would stagnate. Yet, it is a double-edged sword. An excess of mutations can have devastating effects on fitness and population viability. It is therefore one of the great challenges of molecular ecology to determine the rate and mechanisms by which these mutations accrue across the tree of life. Advances in high-throughput sequencing technologies are providing new opportunities for characterizing the rates and mutational spectra within species and populations thus informing essential evolutionary parameters such as the timing of speciation events, the intricacies of historical demography, and the degree to which lineages are subject to the burdens of mutational load. Here, we will focus on both the challenge and promise of whole-genome comparisons among parents and their offspring from known pedigrees for the detection of germline mutations as they arise in a single generation. The potential of these studies is high, but the field is still in its infancy and much uncertainty remains. Namely, the technical challenges are daunting given that pedigree-based genome comparisons are essentially searching for needles in a haystack given the very low signal to noise ratio. Despite the challenges, we predict that rapidly developing methods for whole-genome comparisons hold great promise for integrating empirically derived estimates of de novo mutation rates and mutation spectra across many molecular ecological applications.
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Affiliation(s)
- Anne D Yoder
- Department of Biology, Duke University, Durham, NC, USA
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17
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Stability across the Whole Nuclear Genome in the Presence and Absence of DNA Mismatch Repair. Cells 2021; 10:cells10051224. [PMID: 34067668 PMCID: PMC8156620 DOI: 10.3390/cells10051224] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 05/13/2021] [Accepted: 05/14/2021] [Indexed: 01/06/2023] Open
Abstract
We describe the contribution of DNA mismatch repair (MMR) to the stability of the eukaryotic nuclear genome as determined by whole-genome sequencing. To date, wild-type nuclear genome mutation rates are known for over 40 eukaryotic species, while measurements in mismatch repair-defective organisms are fewer in number and are concentrated on Saccharomyces cerevisiae and human tumors. Well-studied organisms include Drosophila melanogaster and Mus musculus, while less genetically tractable species include great apes and long-lived trees. A variety of techniques have been developed to gather mutation rates, either per generation or per cell division. Generational rates are described through whole-organism mutation accumulation experiments and through offspring–parent sequencing, or they have been identified by descent. Rates per somatic cell division have been estimated from cell line mutation accumulation experiments, from systemic variant allele frequencies, and from widely spaced samples with known cell divisions per unit of tissue growth. The latter methods are also used to estimate generational mutation rates for large organisms that lack dedicated germlines, such as trees and hyphal fungi. Mechanistic studies involving genetic manipulation of MMR genes prior to mutation rate determination are thus far confined to yeast, Arabidopsis thaliana, Caenorhabditis elegans, and one chicken cell line. A great deal of work in wild-type organisms has begun to establish a sound baseline, but far more work is needed to uncover the variety of MMR across eukaryotes. Nonetheless, the few MMR studies reported to date indicate that MMR contributes 100-fold or more to genome stability, and they have uncovered insights that would have been impossible to obtain using reporter gene assays.
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18
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Bergeron LA, Besenbacher S, Bakker J, Zheng J, Li P, Pacheco G, Sinding MHS, Kamilari M, Gilbert MTP, Schierup MH, Zhang G. The germline mutational process in rhesus macaque and its implications for phylogenetic dating. Gigascience 2021; 10:giab029. [PMID: 33954793 PMCID: PMC8099771 DOI: 10.1093/gigascience/giab029] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 01/05/2021] [Accepted: 03/29/2021] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Understanding the rate and pattern of germline mutations is of fundamental importance for understanding evolutionary processes. RESULTS Here we analyzed 19 parent-offspring trios of rhesus macaques (Macaca mulatta) at high sequencing coverage of ∼76× per individual and estimated a mean rate of 0.77 × 10-8de novo mutations per site per generation (95% CI: 0.69 × 10-8 to 0.85 × 10-8). By phasing 50% of the mutations to parental origins, we found that the mutation rate is positively correlated with the paternal age. The paternal lineage contributed a mean of 81% of the de novo mutations, with a trend of an increasing male contribution for older fathers. Approximately 3.5% of de novo mutations were shared between siblings, with no parental bias, suggesting that they arose from early development (postzygotic) stages. Finally, the divergence times between closely related primates calculated on the basis of the yearly mutation rate of rhesus macaque generally reconcile with divergence estimated with molecular clock methods, except for the Cercopithecoidea/Hominoidea molecular divergence dated at 58 Mya using our new estimate of the yearly mutation rate. CONCLUSIONS When compared to the traditional molecular clock methods, new estimated rates from pedigree samples can provide insights into the evolution of well-studied groups such as primates.
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Affiliation(s)
- Lucie A Bergeron
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen Ø, Denmark
| | - Søren Besenbacher
- Department of Molecular Medicine, Aarhus University, Brendstrupgårdsvej 21A, 8200 Aarhus N, Denmark
| | - Jaco Bakker
- Animal Science Department, Biomedical Primate Research Centre, Lange Kleiweg 161, 2288 GJ Rijswijk, Netherlands
| | - Jiao Zheng
- BGI-Shenzhen, Shenzhen 518083, Guangdong, China
- BGI Education Center, University of Chinese Academy of Sciences, Shenzhen 518083, Guangdong, China
| | - Panyi Li
- BGI-Shenzhen, Shenzhen 518083, Guangdong, China
| | - George Pacheco
- Section for Evolutionary Genomics, The GLOBE Institute, University of Copenhagen, Oester Voldgade 5-7, 1350 Copenhagen K, Denmark
| | - Mikkel-Holger S Sinding
- Department of genetics, Trinity College Dublin, 2 college green, D02 VF25, Dublin, Ireland
- Greenland Institute of Natural Resources, Kivioq 2, 3900 Nuuk, Greenland
| | - Maria Kamilari
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen Ø, Denmark
| | - M Thomas P Gilbert
- Section for Evolutionary Genomics, The GLOBE Institute, University of Copenhagen, Oester Voldgade 5-7, 1350 Copenhagen K, Denmark
- Department of Natural History, NTNU University Museum, Norwegian University of Science and Technology (NTNU), NO-7491 Trondheim, Norway
| | - Mikkel H Schierup
- Bioinformatics Research Centre, Aarhus University, C.F.Møllers Allé 8, 8000, Aarhus C, Denmark
| | - Guojie Zhang
- Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Universitetsparken 15, 2100 Copenhagen Ø, Denmark
- BGI-Shenzhen, Shenzhen 518083, Guangdong, China
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China
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19
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Yang C, Zhou Y, Marcus S, Formenti G, Bergeron LA, Song Z, Bi X, Bergman J, Rousselle MMC, Zhou C, Zhou L, Deng Y, Fang M, Xie D, Zhu Y, Tan S, Mountcastle J, Haase B, Balacco J, Wood J, Chow W, Rhie A, Pippel M, Fabiszak MM, Koren S, Fedrigo O, Freiwald WA, Howe K, Yang H, Phillippy AM, Schierup MH, Jarvis ED, Zhang G. Evolutionary and biomedical insights from a marmoset diploid genome assembly. Nature 2021; 594:227-233. [PMID: 33910227 PMCID: PMC8189906 DOI: 10.1038/s41586-021-03535-x] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2020] [Accepted: 04/12/2021] [Indexed: 01/23/2023]
Abstract
The accurate and complete assembly of both haplotype sequences of a diploid organism is essential to understanding the role of variation in genome functions, phenotypes and diseases1. Here, using a trio-binning approach, we present a high-quality, diploid reference genome, with both haplotypes assembled independently at the chromosome level, for the common marmoset (Callithrix jacchus), an primate model system that is widely used in biomedical research2,3. The full spectrum of heterozygosity between the two haplotypes involves 1.36% of the genome-much higher than the 0.13% indicated by the standard estimation based on single-nucleotide heterozygosity alone. The de novo mutation rate is 0.43 × 10-8 per site per generation, and the paternal inherited genome acquired twice as many mutations as the maternal. Our diploid assembly enabled us to discover a recent expansion of the sex-differentiation region and unique evolutionary changes in the marmoset Y chromosome. In addition, we identified many genes with signatures of positive selection that might have contributed to the evolution of Callithrix biological features. Brain-related genes were highly conserved between marmosets and humans, although several genes experienced lineage-specific copy number variations or diversifying selection, with implications for the use of marmosets as a model system.
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Affiliation(s)
- Chentao Yang
- BGI-Shenzhen, Shenzhen, China.,Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | | | - Stephanie Marcus
- Laboratory of Neurogenetics of Language, The Rockefeller University, New York, NY, USA
| | - Giulio Formenti
- Laboratory of Neurogenetics of Language, The Rockefeller University, New York, NY, USA.,Vertebrate Genome Laboratory, The Rockefeller University, New York, NY, USA
| | - Lucie A Bergeron
- Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Zhenzhen Song
- University of the Chinese Academy of Sciences, Beijing, China
| | | | - Juraj Bergman
- Bioinformatics Research Centre, Aarhus University, Aarhus, Denmark
| | | | | | | | - Yuan Deng
- BGI-Shenzhen, Shenzhen, China.,Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | | | - Duo Xie
- BGI-Shenzhen, Shenzhen, China
| | | | | | | | - Bettina Haase
- Vertebrate Genome Laboratory, The Rockefeller University, New York, NY, USA
| | - Jennifer Balacco
- Vertebrate Genome Laboratory, The Rockefeller University, New York, NY, USA
| | | | | | - Arang Rhie
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Martin Pippel
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.,Center for Systems Biology, Dresden, Germany
| | | | - Sergey Koren
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Olivier Fedrigo
- Vertebrate Genome Laboratory, The Rockefeller University, New York, NY, USA
| | - Winrich A Freiwald
- Laboratory of Neural Systems, The Rockefeller University, New York, NY, USA.,Center for Brains, Minds and Machines (CBMM), The Rockefeller University, New York, NY, USA
| | | | - Huanming Yang
- BGI-Shenzhen, Shenzhen, China.,University of the Chinese Academy of Sciences, Beijing, China.,James D. Watson Institute of Genome Sciences, Hangzhou, China.,Guangdong Provincial Academician Workstation of BGI Synthetic Genomics, BGI-Shenzhen, Shenzhen, China
| | - Adam M Phillippy
- Genome Informatics Section, Computational and Statistical Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | | | - Erich D Jarvis
- Laboratory of Neurogenetics of Language, The Rockefeller University, New York, NY, USA.,Vertebrate Genome Laboratory, The Rockefeller University, New York, NY, USA.,Howard Hughes Medical Institute, Chevy Chase, MD, USA
| | - Guojie Zhang
- Villum Centre for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark. .,State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China. .,China National GeneBank, BGI-Shenzhen, Shenzhen, China. .,Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, China.
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20
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Abstract
Despite its important biological role, the evolution of recombination rates remains relatively poorly characterized. This owes, in part, to the lack of high-quality genomic resources to address this question across diverse species. Humans and our closest evolutionary relatives, anthropoid apes, have remained a major focus of large-scale sequencing efforts, and thus recombination rate variation has been comparatively well studied in this group-with earlier work revealing a conservation at the broad- but not the fine-scale. However, in order to better understand the nature of this variation, and the time scales on which substantial modifications occur, it is necessary to take a broader phylogenetic perspective. I here present the first fine-scale genetic map for vervet monkeys based on whole-genome population genetic data from ten individuals and perform a series of comparative analyses with the great apes. The results reveal a number of striking features. First, owing to strong positive correlations with diversity and weak negative correlations with divergence, analyses suggest a dominant role for purifying and background selection in shaping patterns of variation in this species. Second, results support a generally reduced broad-scale recombination rate compared with the great apes, as well as a narrower fraction of the genome in which the majority of recombination events are observed to occur. Taken together, this data set highlights the great necessity of future research to identify genomic features and quantify evolutionary processes that are driving these rate changes across primates.
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Affiliation(s)
- Susanne P Pfeifer
- Center for Evolution and Medicine, School of Life Sciences, Arizona State University, Tempe, AZ
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21
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Ayoola AO, Zhang BL, Meisel RP, Nneji LM, Shao Y, Morenikeji OB, Adeola AC, Ng’ang’a SI, Ogunjemite BG, Okeyoyin AO, Roos C, Wu DD. Population Genomics Reveals Incipient Speciation, Introgression, and Adaptation in the African Mona Monkey (Cercopithecus mona). Mol Biol Evol 2021; 38:876-890. [PMID: 32986826 PMCID: PMC7947840 DOI: 10.1093/molbev/msaa248] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Guenons (tribe Cercopithecini) are the most widely distributed nonhuman primate in the tropical forest belt of Africa and show considerable phenotypic, taxonomic, and ecological diversity. However, genomic information for most species within this group is still lacking. Here, we present a high-quality de novo genome (total 2.90 Gb, contig N50 equal to 22.7 Mb) of the mona monkey (Cercopithecus mona), together with genome resequencing data of 13 individuals sampled across Nigeria. Our results showed differentiation between populations from East and West of the Niger River ∼84 ka and potential ancient introgression in the East population from other mona group species. The PTPRK, FRAS1, BNC2, and EDN3 genes related to pigmentation displayed signals of introgression in the East population. Genomic scans suggest that immunity genes such as AKT3 and IL13 (possibly involved in simian immunodeficiency virus defense), and G6PD, a gene involved in malaria resistance, are under positive natural selection. Our study gives insights into differentiation, natural selection, and introgression in guenons.
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Affiliation(s)
- Adeola Oluwakemi Ayoola
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Kunming College of Life Science, University of the Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Bao-Lin Zhang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Richard P Meisel
- Department of Biology and Biochemistry, University of Houston, Houston, TX
| | - Lotanna M Nneji
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Yong Shao
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Olanrewaju B Morenikeji
- Department of Biomedical Sciences, Rochester Institute of Technology, Rochester, NY
- Department of Biology, Hamilton College, Clinton, NY
| | - Adeniyi C Adeola
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Sino-Africa Joint Research Center, Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Said I Ng’ang’a
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Kunming College of Life Science, University of the Chinese Academy of Sciences, Kunming, Yunnan, China
| | - Babafemi G Ogunjemite
- Department of Ecotourism and Wildlife Management, Federal University of Technology, Akure, Nigeria
| | - Agboola O Okeyoyin
- National Park Service Headquarters, Federal Capital Territory, Abuja, Nigeria
| | - Christian Roos
- Gene Bank of Primates and Primate Genetics Laboratory, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
| | - Dong-Dong Wu
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- National Resource Center for Non-Human Primates, Kunming Primate Research Center, and National Research Facility for Phenotypic & Genetic Analysis of Model Animals (Primate Facility), Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, Yunnan, China
- Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming, Yunnan, China
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22
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Wu FL, Strand AI, Cox LA, Ober C, Wall JD, Moorjani P, Przeworski M. A comparison of humans and baboons suggests germline mutation rates do not track cell divisions. PLoS Biol 2020; 18:e3000838. [PMID: 32804933 PMCID: PMC7467331 DOI: 10.1371/journal.pbio.3000838] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 09/02/2020] [Accepted: 07/28/2020] [Indexed: 12/19/2022] Open
Abstract
In humans, most germline mutations are inherited from the father. This observation has been widely interpreted as reflecting the replication errors that accrue during spermatogenesis. If so, the male bias in mutation should be substantially lower in a closely related species with similar rates of spermatogonial stem cell divisions but a shorter mean age of reproduction. To test this hypothesis, we resequenced two 3-4 generation nuclear families (totaling 29 individuals) of olive baboons (Papio anubis), who reproduce at approximately 10 years of age on average, and analyzed the data in parallel with three 3-generation human pedigrees (26 individuals). We estimated a mutation rate per generation in baboons of 0.57×10-8 per base pair, approximately half that of humans. Strikingly, however, the degree of male bias in germline mutations is approximately 4:1, similar to that of humans-indeed, a similar male bias is seen across mammals that reproduce months, years, or decades after birth. These results mirror the finding in humans that the male mutation bias is stable with parental ages and cast further doubt on the assumption that germline mutations track cell divisions. Our mutation rate estimates for baboons raise a further puzzle, suggesting a divergence time between apes and Old World monkeys of 65 million years, too old to be consistent with the fossil record; reconciling them now requires not only a slowdown of the mutation rate per generation in humans but also in baboons.
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Affiliation(s)
- Felix L. Wu
- Department of Systems Biology, Columbia University, New York, New York, United States of America
- Integrated Program in Cellular, Molecular, and Biomedical Studies, Columbia University, New York, New York, United States of America
| | - Alva I. Strand
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
| | - Laura A. Cox
- Center for Precision Medicine, Department of Internal Medicine, Section of Molecular Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, United States of America
- Southwest National Primate Research Center, Texas Biomedical Research Institute, San Antonio, Texas, United States of America
| | - Carole Ober
- Department of Human Genetics, The University of Chicago, Chicago, Illinois, United States of America
| | - Jeffrey D. Wall
- Institute for Human Genetics, Department of Epidemiology & Biostatistics, University of California, San Francisco, San Francisco, California, United States of America
| | - Priya Moorjani
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
| | - Molly Przeworski
- Department of Systems Biology, Columbia University, New York, New York, United States of America
- Department of Biological Sciences, Columbia University, New York, New York, United States of America
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23
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Molecular Clocks without Rocks: New Solutions for Old Problems. Trends Genet 2020; 36:845-856. [PMID: 32709458 DOI: 10.1016/j.tig.2020.06.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 06/02/2020] [Accepted: 06/11/2020] [Indexed: 02/07/2023]
Abstract
Molecular data have been used to date species divergences ever since they were described as documents of evolutionary history in the 1960s. Yet, an inadequate fossil record and discordance between gene trees and species trees are persistently problematic. We examine how, by accommodating gene tree discordance and by scaling branch lengths to absolute time using mutation rate and generation time, multispecies coalescent (MSC) methods can potentially overcome these challenges. We find that time estimates can differ - in some cases, substantially - depending on whether MSC methods or traditional phylogenetic methods that apply concatenation are used, and whether the tree is calibrated with pedigree-based mutation rates or with fossils. We discuss the advantages and shortcomings of both approaches and provide practical guidance for data analysis when using these methods.
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24
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Chintalapati M, Moorjani P. Evolution of the mutation rate across primates. Curr Opin Genet Dev 2020; 62:58-64. [PMID: 32634682 DOI: 10.1016/j.gde.2020.05.028] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 05/10/2020] [Accepted: 05/22/2020] [Indexed: 12/31/2022]
Abstract
Germline mutations are the source of all heritable variation. In the past few years, whole genome sequencing has allowed direct and comprehensive surveys of mutation patterns in humans and other species. These studies have documented substantial variation in both mutation rates and spectra across primates, the causes of which remain unclear. Here, we review what is currently known about mutation rates in primates, highlight the factors proposed to explain the variation across species, and discuss some implications of these findings on our understanding of the chronology of primate evolution and the process of mutagenesis.
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Affiliation(s)
- Manjusha Chintalapati
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, United States; Center for Computational Biology, University of California, Berkeley, CA, United States
| | - Priya Moorjani
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, United States; Center for Computational Biology, University of California, Berkeley, CA, United States.
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25
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van der Valk T, Gonda CM, Silegowa H, Almanza S, Sifuentes-Romero I, Hart TB, Hart JA, Detwiler KM, Guschanski K. The Genome of the Endangered Dryas Monkey Provides New Insights into the Evolutionary History of the Vervets. Mol Biol Evol 2020; 37:183-194. [PMID: 31529046 PMCID: PMC6984364 DOI: 10.1093/molbev/msz213] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Genomic data can be a powerful tool for inferring ecology, behavior, and conservation needs of highly elusive species, particularly, when other sources of information are hard to come by. Here, we focus on the Dryas monkey (Cercopithecus dryas), an endangered primate endemic to the Congo Basin with cryptic behavior and possibly <250 remaining adult individuals. Using whole-genome sequencing data, we show that the Dryas monkey represents a sister lineage to the vervets (Chlorocebus sp.) and has diverged from them ∼1.4 Ma with additional bidirectional gene flow ∼750,000–∼500,000 years ago that has likely involved the crossing of the Congo River. Together with evidence of gene flow across the Congo River in bonobos and okapis, our results suggest that the fluvial topology of the Congo River might have been more dynamic than previously recognized. Despite the presence of several homozygous loss-of-function mutations in genes associated with sperm mobility and immunity, we find high genetic diversity and low levels of inbreeding and genetic load in the studied Dryas monkey individual. This suggests that the current population carries sufficient genetic variability for long-term survival and might be larger than currently recognized. We thus provide an example of how genomic data can directly improve our understanding of highly elusive species.
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Affiliation(s)
- Tom van der Valk
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Catalina M Gonda
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
| | - Henri Silegowa
- Frankfurt Zoological Society, TL2 Project, Kinshasa, Democratic Republic of the Congo
| | - Sandra Almanza
- Department of Anthropology, Florida Atlantic University, Boca Raton, FL
| | | | - Terese B Hart
- Frankfurt Zoological Society, TL2 Project, Kinshasa, Democratic Republic of the Congo
| | - John A Hart
- Frankfurt Zoological Society, TL2 Project, Kinshasa, Democratic Republic of the Congo
| | - Kate M Detwiler
- Department of Anthropology, Florida Atlantic University, Boca Raton, FL.,Department of Biological Sciences, Florida Atlantic University, Boca Raton, FL
| | - Katerina Guschanski
- Animal Ecology, Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, Uppsala, Sweden
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26
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Monaghan P, Metcalfe NB. The deteriorating soma and the indispensable germline: gamete senescence and offspring fitness. Proc Biol Sci 2019; 286:20192187. [PMID: 31847776 DOI: 10.1098/rspb.2019.2187] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The idea that there is an impenetrable barrier that separates the germline and soma has shaped much thinking in evolutionary biology and in many other disciplines. However, recent research has revealed that the so-called 'Weismann Barrier' is leaky, and that information is transferred from soma to germline. Moreover, the germline itself is now known to age, and to be influenced by an age-related deterioration of the soma that houses and protects it. This could reduce the likelihood of successful reproduction by old individuals, but also lead to long-term deleterious consequences for any offspring that they do produce (including a shortened lifespan). Here, we review the evidence from a diverse and multidisciplinary literature for senescence in the germline and its consequences; we also examine the underlying mechanisms responsible, emphasizing changes in mutation rate, telomere loss, and impaired mitochondrial function in gametes. We consider the effect on life-history evolution, particularly reproductive scheduling and mate choice. Throughout, we draw attention to unresolved issues, new questions to consider, and areas where more research is needed. We also highlight the need for a more comparative approach that would reveal the diversity of processes that organisms have evolved to slow or halt age-related germline deterioration.
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Affiliation(s)
- Pat Monaghan
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
| | - Neil B Metcalfe
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Graham Kerr Building, Glasgow G12 8QQ, UK
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27
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Koch EM, Schweizer RM, Schweizer TM, Stahler DR, Smith DW, Wayne RK, Novembre J. De Novo Mutation Rate Estimation in Wolves of Known Pedigree. Mol Biol Evol 2019; 36:2536-2547. [PMID: 31297530 PMCID: PMC6805234 DOI: 10.1093/molbev/msz159] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Revised: 06/18/2019] [Accepted: 06/24/2019] [Indexed: 12/11/2022] Open
Abstract
Knowledge of mutation rates is crucial for calibrating population genetics models of demographic history in units of years. However, mutation rates remain challenging to estimate because of the need to identify extremely rare events. We estimated the nuclear mutation rate in wolves by identifying de novo mutations in a pedigree of seven wolves. Putative de novo mutations were discovered by whole-genome sequencing and were verified by Sanger sequencing of parents and offspring. Using stringent filters and an estimate of the false negative rate in the remaining observable genome, we obtain an estimate of ∼4.5 × 10-9 per base pair per generation and provide conservative bounds between 2.6 × 10-9 and 7.1 × 10-9. Although our estimate is consistent with recent mutation rate estimates from ancient DNA (4.0 × 10-9 and 3.0-4.5 × 10-9), it suggests a wider possible range. We also examined the consequences of our rate and the accompanying interval for dating several critical events in canid demographic history. For example, applying our full range of rates to coalescent models of dog and wolf demographic history implies a wide set of possible divergence times between the ancestral populations of dogs and extant Eurasian wolves (16,000-64,000 years ago) although our point estimate indicates a date between 25,000 and 33,000 years ago. Aside from one study in mice, ours provides the only direct mammalian mutation rate outside of primates and is likely to be vital to future investigations of mutation rate evolution.
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Affiliation(s)
- Evan M Koch
- Department of Ecology and Evolution, University of Chicago, Chicago, IL
| | - Rena M Schweizer
- Division of Biological Sciences, University of Montana, Missoula, MT
| | - Teia M Schweizer
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA
- Department of Biology, Colorado State University, Fort Collins, CO
| | - Daniel R Stahler
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park, WY
| | - Douglas W Smith
- Yellowstone Center for Resources, National Park Service, Yellowstone National Park, WY
| | - Robert K Wayne
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA
| | - John Novembre
- Department of Ecology and Evolution, University of Chicago, Chicago, IL
- Department of Human Genetics, University of Chicago, Chicago, IL
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28
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Abstract
Primordial germ cells (PGCs) must complete a complex and dynamic developmental program during embryogenesis to establish the germline. This process is highly conserved and involves a diverse array of tasks required of PGCs, including migration, survival, sex differentiation, and extensive epigenetic reprogramming. A common theme across many organisms is that PGC success is heterogeneous: only a portion of all PGCs complete all these steps while many other PGCs are eliminated from further germline contribution. The differences that distinguish successful PGCs as a population are not well understood. Here, we examine variation that exists in PGCs as they navigate the many stages of this developmental journey. We explore potential sources of PGC heterogeneity and their potential implications in affecting germ cell behaviors. Lastly, we discuss the potential for PGC development to function as a multistage selection process that assesses heterogeneity in PGCs to refine germline quality.
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Affiliation(s)
- Daniel H Nguyen
- Department of Obstetrics, Gynecology and Reproductive Science, Center for Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA, United States
| | - Rebecca G Jaszczak
- Department of Obstetrics, Gynecology and Reproductive Science, Center for Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA, United States
| | - Diana J Laird
- Department of Obstetrics, Gynecology and Reproductive Science, Center for Reproductive Sciences, Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research, University of California, San Francisco, CA, United States.
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29
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Katju V, Bergthorsson U. Old Trade, New Tricks: Insights into the Spontaneous Mutation Process from the Partnering of Classical Mutation Accumulation Experiments with High-Throughput Genomic Approaches. Genome Biol Evol 2019; 11:136-165. [PMID: 30476040 PMCID: PMC6330053 DOI: 10.1093/gbe/evy252] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2018] [Indexed: 12/17/2022] Open
Abstract
Mutations spawn genetic variation which, in turn, fuels evolution. Hence, experimental investigations into the rate and fitness effects of spontaneous mutations are central to the study of evolution. Mutation accumulation (MA) experiments have served as a cornerstone for furthering our understanding of spontaneous mutations for four decades. In the pregenomic era, phenotypic measurements of fitness-related traits in MA lines were used to indirectly estimate key mutational parameters, such as the genomic mutation rate, new mutational variance per generation, and the average fitness effect of mutations. Rapidly emerging next-generating sequencing technology has supplanted this phenotype-dependent approach, enabling direct empirical estimates of the mutation rate and a more nuanced understanding of the relative contributions of different classes of mutations to the standing genetic variation. Whole-genome sequencing of MA lines bears immense potential to provide a unified account of the evolutionary process at multiple levels-the genetic basis of variation, and the evolutionary dynamics of mutations under the forces of selection and drift. In this review, we have attempted to synthesize key insights into the spontaneous mutation process that are rapidly emerging from the partnering of classical MA experiments with high-throughput sequencing, with particular emphasis on the spontaneous rates and molecular properties of different mutational classes in nuclear and mitochondrial genomes of diverse taxa, the contribution of mutations to the evolution of gene expression, and the rate and stability of transgenerational epigenetic modifications. Future advances in sequencing technologies will enable greater species representation to further refine our understanding of mutational parameters and their functional consequences.
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Affiliation(s)
- Vaishali Katju
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843-4458
| | - Ulfar Bergthorsson
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX 77843-4458
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