1
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Combs MA, Golnar AJ, Overcash JM, Lloyd AL, Hayes KR, O'Brochta DA, Pepin KM. Leveraging eco-evolutionary models for gene drive risk assessment. Trends Genet 2023:S0168-9525(23)00090-2. [PMID: 37198063 DOI: 10.1016/j.tig.2023.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 04/07/2023] [Accepted: 04/14/2023] [Indexed: 05/19/2023]
Abstract
Engineered gene drives create potential for both widespread benefits and irreversible harms to ecosystems. CRISPR-based systems of allelic conversion have rapidly accelerated gene drive research across diverse taxa, putting field trials and their necessary risk assessments on the horizon. Dynamic process-based models provide flexible quantitative platforms to predict gene drive outcomes in the context of system-specific ecological and evolutionary features. Here, we synthesize gene drive dynamic modeling studies to highlight research trends, knowledge gaps, and emergent principles, organized around their genetic, demographic, spatial, environmental, and implementation features. We identify the phenomena that most significantly influence model predictions, discuss limitations of biological complexity and uncertainty, and provide insights to promote responsible development and model-assisted risk assessment of gene drives.
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Affiliation(s)
- Matthew A Combs
- National Wildlife Research Center, United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Fort Collins, CO, 80521, USA.
| | - Andrew J Golnar
- National Wildlife Research Center, United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Fort Collins, CO, 80521, USA
| | - Justin M Overcash
- United States Department of Agriculture, Animal and Plant Health Inspection Service, Biotechnology Regulatory Services, 20737, USA
| | - Alun L Lloyd
- North Carolina State University, Biomathematics Graduate Program and Department of Mathematics, Raleigh, NC, 27695, USA
| | - Keith R Hayes
- The Commonwealth Scientific and Industrial Research Organisation, Data 61, Hobart, TAS, 7004, Australia
| | - David A O'Brochta
- Foundation for the National Institutes of Health, North Bethesda, MD, 20852, USA
| | - Kim M Pepin
- National Wildlife Research Center, United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Fort Collins, CO, 80521, USA
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2
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Frieß JL, Lalyer CR, Giese B, Simon S, Otto M. Review of gene drive modelling and implications for risk assessment of gene drive organisms. Ecol Modell 2023. [DOI: 10.1016/j.ecolmodel.2023.110285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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3
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Abstract
Invasive rodents are a major cause of environmental damage and biodiversity loss, particularly on islands. Unlike insects, genetic biocontrol strategies including population-suppressing gene drives with biased inheritance have not been developed in mice. Here, we demonstrate a gene drive strategy (tCRISPR) that leverages super-Mendelian transmission of the t haplotype to spread inactivating mutations in a haplosufficient female fertility gene (Prl). Using spatially explicit individual-based in silico modeling, we show that tCRISPR can eradicate island populations under a range of realistic field-based parameter values. We also engineer transgenic tCRISPR mice that, crucially, exhibit biased transmission of the modified t haplotype and Prl mutations at levels our modeling predicts would be sufficient for eradication. This is an example of a feasible gene drive system for invasive alien rodent population control.
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4
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Runge JN, Kokko H, Lindholm AK. Selfish migrants: How a meiotic driver is selected to increase dispersal. J Evol Biol 2022; 35:621-632. [PMID: 35255164 PMCID: PMC9311743 DOI: 10.1111/jeb.13989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 02/09/2022] [Accepted: 02/14/2022] [Indexed: 11/28/2022]
Abstract
Meiotic drivers are selfish genetic elements that manipulate meiosis to increase their transmission to the next generation to the detriment of the rest of the genome. One example is the t haplotype in house mice, which is a naturally occurring meiotic driver with deleterious traits—poor fitness in polyandrous matings and homozygote inviability or infertility—that prevent its fixation. Recently, we discovered and validated a novel effect of t in a long‐term field study on free‐living wild house mice and with experiments: t‐carriers are more likely to disperse. Here, we ask what known traits of the t haplotype can select for a difference in dispersal between t‐carriers and wildtype mice. To that end, we built individual‐based models with dispersal loci on the t and the homologous wildtype chromosomes. We also allow for density‐dependent expression of these loci. The t haplotype consistently evolves to increase the dispersal propensity of its carriers, particularly at high densities. By examining variants of the model that modify different costs caused by t, we show that the increase in dispersal is driven by the deleterious traits of t, disadvantage in polyandrous matings and lethal homozygosity or male sterility. Finally, we show that an increase in driver‐carrier dispersal can evolve across a range of values in driver strength and disadvantages.
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Affiliation(s)
- Jan-Niklas Runge
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
| | - Hanna Kokko
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.,Konrad Lorenz Institute of Ethology, University of Veterinary Medicine, Vienna, Austria
| | - Anna K Lindholm
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
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5
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Birand A, Cassey P, Ross JV, Russell JC, Thomas P, Prowse TAA. Gene drives for vertebrate pest control: realistic spatial modelling of eradication probabilities and times for island mouse populations. Mol Ecol 2022; 31:1907-1923. [PMID: 35073448 PMCID: PMC9303646 DOI: 10.1111/mec.16361] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Revised: 01/07/2022] [Accepted: 01/12/2022] [Indexed: 11/29/2022]
Abstract
Invasive alien species continue to threaten global biodiversity. CRISPR‐based gene drives, which can theoretically spread through populations despite imparting a fitness cost, could be used to suppress or eradicate pest populations. We develop an individual‐based, spatially explicit, stochastic model to simulate the ability of CRISPR‐based homing and X chromosome shredding drives to eradicate populations of invasive house mice (Mus muculus) from islands. Using the model, we explore the interactive effect of the efficiency of the drive constructs and the spatial ecology of the target population on the outcome of a gene‐drive release. We also consider the impact of polyandrous mating and sperm competition, which could compromise the efficacy of some gene‐drive strategies. Our results show that both drive strategies could be used to eradicate large populations of mice. Whereas parameters related to drive efficiency and demography strongly influence drive performance, we find that sperm competition following polyandrous mating is unlikely to impact the outcome of an eradication effort substantially. Assumptions regarding the spatial ecology of mice influenced the probability of and time required for eradication, with short‐range dispersal capacities and limited mate‐search areas producing ‘chase’ dynamics across the island characterized by cycles of local extinction and recolonization by mice. We also show that highly efficient drives are not always optimal, when dispersal and mate‐search capabilities are low. Rapid local population suppression around the introduction sites can cause loss of the gene drive before it can spread to the entire island. We conclude that, although the design of efficient gene drives is undoubtedly critical, accurate data on the spatial ecology of target species are critical for predicting the result of a gene‐drive release.
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Affiliation(s)
- Aysegul Birand
- Invasion Science and Wildlife Ecology Lab, School of Biological Sciences, The University of Adelaide, Adelaide, Australia
| | - Phillip Cassey
- Invasion Science and Wildlife Ecology Lab, School of Biological Sciences, The University of Adelaide, Adelaide, Australia
| | - Joshua V Ross
- School of Mathematical Sciences, The University of Adelaide, Adelaide, Australia
| | - James C Russell
- School of Biological Sciences, Department of Statistics, University of Auckland, Auckland, New Zealand
| | - Paul Thomas
- School of Medicine, Robinson Research Institute, The University of Adelaide, Adelaide, Australia.,South Australian Health and Medical Research Institute, Adelaide, Australia
| | - Thomas A A Prowse
- Invasion Science and Wildlife Ecology Lab, School of Biological Sciences, The University of Adelaide, Adelaide, Australia
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6
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Weitzel AJ, Grunwald HA, Weber C, Levina R, Gantz VM, Hedrick SM, Bier E, Cooper KL. Meiotic Cas9 expression mediates gene conversion in the male and female mouse germline. PLoS Biol 2021; 19:e3001478. [PMID: 34941868 PMCID: PMC8699911 DOI: 10.1371/journal.pbio.3001478] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Accepted: 11/10/2021] [Indexed: 11/18/2022] Open
Abstract
Highly efficient gene conversion systems have the potential to facilitate the study of complex genetic traits using laboratory mice and, if implemented as a "gene drive," to limit loss of biodiversity and disease transmission caused by wild rodent populations. We previously showed that such a system of gene conversion from heterozygous to homozygous after a sequence targeted CRISPR/Cas9 double-strand DNA break (DSB) is feasible in the female mouse germline. In the male germline, however, all DSBs were instead repaired by end joining (EJ) mechanisms to form an "insertion/deletion" (indel) mutation. These observations suggested that timing Cas9 expression to coincide with meiosis I is critical to favor conditions when homologous chromosomes are aligned and interchromosomal homology-directed repair (HDR) mechanisms predominate. Here, using a Cas9 knock-in allele at the Spo11 locus, we show that meiotic expression of Cas9 does indeed mediate gene conversion in the male as well as in the female germline. However, the low frequency of both HDR and indel mutation in both male and female germlines suggests that Cas9 may be expressed from the Spo11 locus at levels too low for efficient DSB formation. We suggest that more robust Cas9 expression initiated during early meiosis I may improve the efficiency of gene conversion and further increase the rate of "super-mendelian" inheritance from both male and female mice.
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Affiliation(s)
- Alexander J. Weitzel
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
| | - Hannah A. Grunwald
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
| | - Ceri Weber
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
| | - Rimma Levina
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
| | - Valentino M. Gantz
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
| | - Stephen M. Hedrick
- Division of Biological Sciences, Section of Molecular Biology, University of California San Diego, La Jolla, California, United States of America
| | - Ethan Bier
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
- Tata Institute for Genetics and Society, University of California San Diego, La Jolla, California, United States of America
| | - Kimberly L. Cooper
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California San Diego, La Jolla, California, United States of America
- Tata Institute for Genetics and Society, University of California San Diego, La Jolla, California, United States of America
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7
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Genome-Wide SNP Analysis Reveals Multiple Paternity in Burmese Pythons Invasive to the Greater Florida Everglades. J HERPETOL 2021. [DOI: 10.1670/20-104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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8
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Edgington MP, Harvey-Samuel T, Alphey L. Split drive killer-rescue provides a novel threshold-dependent gene drive. Sci Rep 2020; 10:20520. [PMID: 33239631 PMCID: PMC7689494 DOI: 10.1038/s41598-020-77544-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Accepted: 11/12/2020] [Indexed: 12/20/2022] Open
Abstract
A wide range of gene drive mechanisms have been proposed that are predicted to increase in frequency within a population even when they are deleterious to individuals carrying them. This also allows associated desirable genetic material ("cargo genes") to increase in frequency. Gene drives have garnered much attention for their potential use against a range of globally important problems including vector borne disease, crop pests and invasive species. Here we propose a novel gene drive mechanism that could be engineered using a combination of toxin-antidote and CRISPR components, each of which are already being developed for other purposes. Population genetics mathematical models are developed here to demonstrate the threshold-dependent nature of the proposed system and its robustness to imperfect homing, incomplete penetrance of toxins and transgene fitness costs, each of which are of practical significance given that real-world components inevitably have such imperfections. We show that although end-joining repair mechanisms may cause the system to break down, under certain conditions, it should persist over time scales relevant for genetic control programs. The potential of such a system to provide localised population suppression via sex ratio distortion or female-specific lethality is also explored. Additionally, we investigate the effect on introduction thresholds of adding an extra CRISPR base element, showing that this may either increase or decrease dependent on parameter context.
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Affiliation(s)
| | - Tim Harvey-Samuel
- The Pirbright Institute, Ash Road, Woking, Surrey, Pirbright, GU24 0NF, UK
| | - Luke Alphey
- The Pirbright Institute, Ash Road, Woking, Surrey, Pirbright, GU24 0NF, UK
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9
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Manser A, König B, Lindholm AK. Polyandry blocks gene drive in a wild house mouse population. Nat Commun 2020; 11:5590. [PMID: 33149121 PMCID: PMC7643059 DOI: 10.1038/s41467-020-18967-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 09/21/2020] [Indexed: 12/18/2022] Open
Abstract
Gene drives are genetic elements that manipulate Mendelian inheritance ratios in their favour. Understanding the forces that explain drive frequency in natural populations is a long-standing focus of evolutionary research. Recently, the possibility to create artificial drive constructs to modify pest populations has exacerbated our need to understand how drive spreads in natural populations. Here, we study the impact of polyandry on a well-known gene drive, called t haplotype, in an intensively monitored population of wild house mice. First, we show that house mice are highly polyandrous: 47% of 682 litters were sired by more than one male. Second, we find that drive-carrying males are particularly compromised in sperm competition, resulting in reduced reproductive success. As a result, drive frequency decreased during the 4.5 year observation period. Overall, we provide the first direct evidence that the spread of a gene drive is hampered by reproductive behaviour in a natural population. This study resolves a long-standing mystery of why t haplotypes, an example of selfish genes, have persisted at unexpectedly low frequencies in wild mouse populations. It shows that multiple mating by females, which is more common at higher mouse population densities, decreases the frequency of driving t haplotypes.
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Affiliation(s)
- Andri Manser
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland. .,Department of Evolution, Ecology and Behaviour, University of Liverpool, Biosciences Building, Crown Street, Liverpool, UK.
| | - Barbara König
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland
| | - Anna K Lindholm
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, Zurich, Switzerland
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10
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Naegeli H, Bresson J, Dalmay T, Dewhurst IC, Epstein MM, Guerche P, Hejatko J, Moreno FJ, Mullins E, Nogué F, Rostoks N, Sánchez Serrano JJ, Savoini G, Veromann E, Veronesi F, Bonsall MB, Mumford J, Wimmer EA, Devos Y, Paraskevopoulos K, Firbank LG. Adequacy and sufficiency evaluation of existing EFSA guidelines for the molecular characterisation, environmental risk assessment and post-market environmental monitoring of genetically modified insects containing engineered gene drives. EFSA J 2020; 18:e06297. [PMID: 33209154 PMCID: PMC7658669 DOI: 10.2903/j.efsa.2020.6297] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Advances in molecular and synthetic biology are enabling the engineering of gene drives in insects for disease vector/pest control. Engineered gene drives (that bias their own inheritance) can be designed either to suppress interbreeding target populations or modify them with a new genotype. Depending on the engineered gene drive system, theoretically, a genetic modification of interest could spread through target populations and persist indefinitely, or be restricted in its spread or persistence. While research on engineered gene drives and their applications in insects is advancing at a fast pace, it will take several years for technological developments to move to practical applications for deliberate release into the environment. Some gene drive modified insects (GDMIs) have been tested experimentally in the laboratory, but none has been assessed in small-scale confined field trials or in open release trials as yet. There is concern that the deliberate release of GDMIs in the environment may have possible irreversible and unintended consequences. As a proactive measure, the European Food Safety Authority (EFSA) has been requested by the European Commission to review whether its previously published guidelines for the risk assessment of genetically modified animals (EFSA, 2012 and 2013), including insects (GMIs), are adequate and sufficient for GDMIs, primarily disease vectors, agricultural pests and invasive species, for deliberate release into the environment. Under this mandate, EFSA was not requested to develop risk assessment guidelines for GDMIs. In this Scientific Opinion, the Panel on Genetically Modified Organisms (GMO) concludes that EFSA's guidelines are adequate, but insufficient for the molecular characterisation (MC), environmental risk assessment (ERA) and post-market environmental monitoring (PMEM) of GDMIs. While the MC,ERA and PMEM of GDMIs can build on the existing risk assessment framework for GMIs that do not contain engineered gene drives, there are specific areas where further guidance is needed for GDMIs.
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11
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Keais GL, Lu S, Perlman SJ. Autosomal suppression and fitness costs of an old driving X chromosome in Drosophila testacea. J Evol Biol 2020; 33:619-628. [PMID: 31990433 DOI: 10.1111/jeb.13596] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 12/18/2019] [Accepted: 01/07/2020] [Indexed: 12/19/2022]
Abstract
Driving X chromosomes (XD s) bias their own transmission through males by killing Y-bearing gametes. These chromosomes can in theory spread rapidly in populations and cause extinction, but many are found as balanced polymorphisms or as "cryptic" XD s shut down by drive suppressors. The relative likelihood of these outcomes and the evolutionary pathways through which they come about are not well understood. An XD was recently discovered in the mycophagous fly, Drosophila testacea, presenting the opportunity to compare this XD with the well-studied XD of its sister species, Drosophila neotestacea. Comparing features of independently evolved XD s in young sister species is a promising avenue towards understanding how XD s and their counteracting forces change over time. In contrast to the XD of D. neotestacea, we find that the XD of D. testacea is old, with its origin predating the radiation of three species: D. testacea, D. neotestacea and their shared sister species, Drosophila orientacea. Motivated by the suggestion that older XD s should be more deleterious to carriers, we assessed the effect of the XD on both male and female fertility. Unlike what is known from D. neotestacea, we found a strong fitness cost in females homozygous for the XD in D. testacea: a large proportion of homozygous females failed to produce offspring after being housed with males for several days. Our male fertility experiments show that although XD male fertility is lower under sperm-depleting conditions, XD males have comparable fertility to males carrying a standard X chromosome under a free-mating regime, which may better approximate conditions in wild populations of D. testacea. Lastly, we demonstrate the presence of autosomal suppression of X chromosome drive. Our results provide support for a model of XD evolution where the dynamics of young XD s are governed by fitness consequences in males, whereas in older XD systems, both suppression and fitness consequences in females likely supersede male fitness costs.
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Affiliation(s)
- Graeme L Keais
- Department of Biology, University of Victoria, Victoria, BC, Canada.,Department of Botany, University of British Columbia, Vancouver, BC, Canada
| | - Sijia Lu
- Department of Biology, University of Victoria, Victoria, BC, Canada
| | - Steve J Perlman
- Department of Biology, University of Victoria, Victoria, BC, Canada
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12
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Dyer KA, Hall DW. Fitness consequences of a non-recombining sex-ratio drive chromosome can explain its prevalence in the wild. Proc Biol Sci 2019; 286:20192529. [PMID: 31847762 DOI: 10.1098/rspb.2019.2529] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Understanding the pleiotropic consequences of gene drive systems on host fitness is essential to predict their spread through a host population. Here, we study sex-ratio (SR) X-chromosome drive in the fly Drosophila recens, where SR causes the death of Y-bearing sperm in male carriers. SR males only sire daughters, which all carry SR, thus giving the chromosome a transmission advantage. The prevalence of the SR chromosome appears stable, suggesting pleiotropic costs. It was previously shown that females homozygous for SR are sterile, and here, we test for additional fitness costs of SR. We found that females heterozygous for SR have reduced fecundity and that male SR carriers have reduced fertility in conditions of sperm competition. We then use our fitness estimates to parametrize theoretical models of SR drive and show that the decrease in fecundity and sperm competition performance can account for the observed prevalence of SR in natural populations. In addition, we found that the expected equilibrium frequency of the SR chromosome is particularly sensitive to the degree of multiple mating and performance in sperm competition. Together, our data suggest that the mating system of the organism should be carefully considered during the development of gene drive systems.
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Affiliation(s)
- Kelly A Dyer
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - David W Hall
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
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13
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Wedell N, Price TAR, Lindholm AK. Gene drive: progress and prospects. Proc Biol Sci 2019; 286:20192709. [PMID: 31847764 PMCID: PMC6939923 DOI: 10.1098/rspb.2019.2709] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 11/26/2019] [Indexed: 12/12/2022] Open
Abstract
Gene drive is a naturally occurring phenomenon in which selfish genetic elements manipulate gametogenesis and reproduction to increase their own transmission to the next generation. Currently, there is great excitement about the potential of harnessing such systems to control major pest and vector populations. If synthetic gene drive systems can be constructed and applied to key species, they may be able to rapidly spread either modifying or eliminating the targeted populations. This approach has been lauded as a revolutionary and efficient mechanism to control insect-borne diseases and crop pests. Driving endosymbionts have already been deployed to combat the transmission of dengue and Zika virus in mosquitoes. However, there are a variety of barriers to successfully implementing gene drive techniques in wild populations. There is a risk that targeted organisms will rapidly evolve an ability to suppress the synthetic drive system, rendering it ineffective. There are also potential risks of synthetic gene drivers invading non-target species or populations. This Special Feature covers the current state of affairs regarding both natural and synthetic gene drive systems with the aim to identify knowledge gaps. By understanding how natural drive systems spread through populations, we may be able to better predict the outcomes of synthetic drive release.
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Affiliation(s)
- N. Wedell
- Department of Biosciences, University of Exeter, Penryn Campus, Penryn TR10 9FE, UK
| | - T. A. R. Price
- Institution for Integrative Biology, University of Liverpool, Liverpool L69 7ZB, UK
| | - A. K. Lindholm
- Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
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14
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Godwin J, Serr M, Barnhill-Dilling SK, Blondel DV, Brown PR, Campbell K, Delborne J, Lloyd AL, Oh KP, Prowse TAA, Saah R, Thomas P. Rodent gene drives for conservation: opportunities and data needs. Proc Biol Sci 2019; 286:20191606. [PMID: 31690240 PMCID: PMC6842857 DOI: 10.1098/rspb.2019.1606] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 10/11/2019] [Indexed: 12/18/2022] Open
Abstract
Invasive rodents impact biodiversity, human health and food security worldwide. The biodiversity impacts are particularly significant on islands, which are the primary sites of vertebrate extinctions and where we are reaching the limits of current control technologies. Gene drives may represent an effective approach to this challenge, but knowledge gaps remain in a number of areas. This paper is focused on what is currently known about natural and developing synthetic gene drive systems in mice, some key areas where key knowledge gaps exist, findings in a variety of disciplines relevant to those gaps and a brief consideration of how engagement at the regulatory, stakeholder and community levels can accompany and contribute to this effort. Our primary species focus is the house mouse, Mus musculus, as a genetic model system that is also an important invasive pest. Our primary application focus is the development of gene drive systems intended to reduce reproduction and potentially eliminate invasive rodents from islands. Gene drive technologies in rodents have the potential to produce significant benefits for biodiversity conservation, human health and food security. A broad-based, multidisciplinary approach is necessary to assess this potential in a transparent, effective and responsible manner.
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Affiliation(s)
- John Godwin
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA
- Genetic Engineering and Society Center, North Carolina State University, Raleigh, NC 27695, USA
- W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695, USA
| | - Megan Serr
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | | | - Dimitri V. Blondel
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695, USA
| | - Peter R. Brown
- Health and Biosecurity, Commonwealth Scientific and Industrial Research Organisation (CSIRO), Canberra, Australian Capital Territory, Australia
| | - Karl Campbell
- Island Conservation, Charles Darwin Avenue, Puerto Ayora, Galapagos Islands, Ecuador
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, Queensland, Australia
| | - Jason Delborne
- Genetic Engineering and Society Center, North Carolina State University, Raleigh, NC 27695, USA
- Department of Forestry and Environmental Resources, North Carolina State University, Raleigh, NC 27695, USA
| | - Alun L. Lloyd
- Department of Mathematics, North Carolina State University, Raleigh, NC 27695, USA
| | - Kevin P. Oh
- National Wildlife Research Center, US Department of Agriculture, Fort Collins, CO 80521, USA
| | - Thomas A. A. Prowse
- School of Mathematical Sciences, The University of Adelaide, Adelaide, South Australia, Australia
| | - Royden Saah
- Genetic Engineering and Society Center, North Carolina State University, Raleigh, NC 27695, USA
- Island Conservation, Charles Darwin Avenue, Puerto Ayora, Galapagos Islands, Ecuador
| | - Paul Thomas
- School of Medicine, The University of Adelaide, Adelaide, South Australia, Australia
- South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
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15
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Manser A, Cornell SJ, Sutter A, Blondel DV, Serr M, Godwin J, Price TAR. Controlling invasive rodents via synthetic gene drive and the role of polyandry. Proc Biol Sci 2019; 286:20190852. [PMID: 31431159 PMCID: PMC6732378 DOI: 10.1098/rspb.2019.0852] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2019] [Accepted: 07/25/2019] [Indexed: 12/25/2022] Open
Abstract
House mice are a major ecosystem pest, particularly threatening island ecosystems as a non-native invasive species. Rapid advances in synthetic biology offer new avenues to control pest species for biodiversity conservation. Recently, a synthetic sperm-killing gene drive construct called t-Sry has been proposed as a means to eradicate target mouse populations owing to a lack of females. A factor that has received little attention in the discussion surrounding such drive applications is polyandry. Previous research has demonstrated that sperm-killing drivers are extremely damaging to a male's sperm competitive ability. Here, we examine the importance of this effect on the t-Sry system using a theoretical model. We find that polyandry substantially hampers the spread of t-Sry such that release efforts have to be increased three- to sixfold for successful eradication. We discuss the implications of our finding for potential pest control programmes, the risk of drive spread beyond the target population, and the emergence of drive resistance. Our work highlights that a solid understanding of the forces that determine drive dynamics in a natural setting is key for successful drive application, and that exploring the natural diversity of gene drives may inform effective gene drive design.
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Affiliation(s)
- Andri Manser
- Institute of Integrative Biology, University of Liverpool, Biosciences Building, Liverpool, UK
| | - Stephen J. Cornell
- Institute of Integrative Biology, University of Liverpool, Biosciences Building, Liverpool, UK
| | - Andreas Sutter
- Centre for Ecology, Evolution and Conservation, University of East Anglia, Norwich, UK
| | - Dimitri V. Blondel
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695-7617, USA
| | - Megan Serr
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695-7617, USA
| | - John Godwin
- Department of Biological Sciences, North Carolina State University, Raleigh, NC 27695-7617, USA
| | - Tom A. R. Price
- Institute of Integrative Biology, University of Liverpool, Biosciences Building, Liverpool, UK
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