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Saddler A, Kreppel KS, Chitnis N, Smith TA, Denz A, Moore JD, Tambwe MM, Moore SJ. The development and evaluation of a self-marking unit to estimate malaria vector survival and dispersal distance. Malar J 2019; 18:441. [PMID: 31870365 PMCID: PMC6929409 DOI: 10.1186/s12936-019-3077-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 12/14/2019] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND A clear understanding of mosquito biology is fundamental to the control efforts of mosquito-borne diseases such as malaria. Mosquito mark-release-recapture (MMRR) experiments are a popular method of measuring the survival and dispersal of disease vectors; however, examples with African malaria vectors are limited. Ethical and technical difficulties involved in carrying out MMRR studies may have held back research in this area and, therefore, a device that marks mosquitoes as they emerge from breeding sites was developed and evaluated to overcome the problems of MMRR. METHODS A modified self-marking unit that marks mosquitoes with fluorescent pigment as they emerge from their breeding site was developed based on a previous design for Culex mosquitoes. The self-marking unit was first evaluated under semi-field conditions with laboratory-reared Anopheles arabiensis to determine the marking success and impact on mosquito survival. Subsequently, a field evaluation of MMRR was conducted in Yombo village, Tanzania, to examine the feasibility of the system. RESULTS During the semi-field evaluation the self-marking units successfully marked 86% of emerging mosquitoes and there was no effect of fluorescent marker on mosquito survival. The unit successfully marked wild male and female Anopheles gambiae sensu lato (s.l.) in sufficiently large numbers to justify its use in MMRR studies. The estimated daily survival probability of An. gambiae s.l. was 0.87 (95% CI 0.69-1.10) and mean dispersal distance was 579 m (95% CI 521-636 m). CONCLUSIONS This study demonstrates the successful use of a self-marking device in an MMRR study with African malaria vectors. This method may be useful in investigating population structure and dispersal of mosquitoes for deployment and evaluation of future vector control tools, such as gene drive, and to better parameterize mathematical models.
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Affiliation(s)
- Adam Saddler
- Ifakara Health Institute, Environmental Health and Ecological Sciences, P.O. Box 74, Bagamoyo, Tanzania.
- Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland.
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland.
| | - Katharina S Kreppel
- Ifakara Health Institute, Environmental Health and Ecological Sciences, P.O. Box 74, Bagamoyo, Tanzania
- Nelson Mandela African Institution of Science and Technology, P.O. Box 447, Tengeru, Tanzania
| | - Nakul Chitnis
- Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Thomas A Smith
- Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Adrian Denz
- Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Jason D Moore
- Ifakara Health Institute, Environmental Health and Ecological Sciences, P.O. Box 74, Bagamoyo, Tanzania
- Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Mgeni M Tambwe
- Ifakara Health Institute, Environmental Health and Ecological Sciences, P.O. Box 74, Bagamoyo, Tanzania
- Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
| | - Sarah J Moore
- Ifakara Health Institute, Environmental Health and Ecological Sciences, P.O. Box 74, Bagamoyo, Tanzania
- Swiss Tropical & Public Health Institute, Socinstrasse 57, 4051, Basel, Switzerland
- University of Basel, Petersplatz 1, 4001, Basel, Switzerland
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102
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Maier T, Wheeler NJ, Namigai EKO, Tycko J, Grewelle RE, Woldeamanuel Y, Klohe K, Perez-Saez J, Sokolow SH, De Leo GA, Yoshino TP, Zamanian M, Reinhard-Rupp J. Gene drives for schistosomiasis transmission control. PLoS Negl Trop Dis 2019; 13:e0007833. [PMID: 31856157 PMCID: PMC6922350 DOI: 10.1371/journal.pntd.0007833] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Schistosomiasis is one of the most important and widespread neglected tropical diseases (NTD), with over 200 million people infected in more than 70 countries; the disease has nearly 800 million people at risk in endemic areas. Although mass drug administration is a cost-effective approach to reduce occurrence, extent, and severity of the disease, it does not provide protection to subsequent reinfection. Interventions that target the parasites’ intermediate snail hosts are a crucial part of the integrated strategy required to move toward disease elimination. The recent revolution in gene drive technology naturally leads to questions about whether gene drives could be used to efficiently spread schistosome resistance traits in a population of snails and whether gene drives have the potential to contribute to reduced disease transmission in the long run. Responsible implementation of gene drives will require solutions to complex challenges spanning multiple disciplines, from biology to policy. This Review Article presents collected perspectives from practitioners of global health, genome engineering, epidemiology, and snail/schistosome biology and outlines strategies for responsible gene drive technology development, impact measurements of gene drives for schistosomiasis control, and gene drive governance. Success in this arena is a function of many factors, including gene-editing specificity and efficiency, the level of resistance conferred by the gene drive, how fast gene drives may spread in a metapopulation over a complex landscape, ecological sustainability, social equity, and, ultimately, the reduction of infection prevalence in humans. With combined efforts from across the broad global health community, gene drives for schistosomiasis control could fortify our defenses against this devastating disease in the future.
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Affiliation(s)
- Theresa Maier
- Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge, United Kingdom
| | - Nicolas James Wheeler
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Global Health Institute of Merck (KGaA), Eysins, Switzerland
| | | | - Josh Tycko
- Department of Genetics, Stanford University School of Medicine, Stanford, California, United States of America
| | - Richard Ernest Grewelle
- Hopkins Marine Station, School of Humanities and Sciences, Stanford University, Pacific Grove, California, United States of America
| | - Yimtubezinash Woldeamanuel
- Department of Microbiology, Immunology & Parasitology, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | | | - Javier Perez-Saez
- Laboratory of Ecohydrology, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Susanne H. Sokolow
- Woods Institute for the Environment, Stanford University, Stanford, California, United States of America
- Marine Science Institute, University of California, Santa Barbara, California, United States of America
| | - Giulio A. De Leo
- Hopkins Marine Station, School of Humanities and Sciences, Stanford University, Pacific Grove, California, United States of America
| | - Timothy P. Yoshino
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Mostafa Zamanian
- Department of Pathobiological Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
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Experimental population modification of the malaria vector mosquito, Anopheles stephensi. PLoS Genet 2019; 15:e1008440. [PMID: 31856182 PMCID: PMC6922335 DOI: 10.1371/journal.pgen.1008440] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 09/19/2019] [Indexed: 12/14/2022] Open
Abstract
Small laboratory cage trials of non-drive and gene-drive strains of the Asian malaria vector mosquito, Anopheles stephensi, were used to investigate release ratios and other strain properties for their impact on transgene spread during simulated population modification. We evaluated the effects of transgenes on survival, male contributions to next-generation populations, female reproductive success and the impact of accumulation of gene drive-resistant genomic target sites resulting from nonhomologous end-joining (NHEJ) mutagenesis during Cas9, guide RNA-mediated cleavage. Experiments with a non-drive, autosomally-linked malaria-resistance gene cassette showed ‘full introduction’ (100% of the insects have at least one copy of the transgene) within 8 weeks (≤ 3 generations) following weekly releases of 10:1 transgenic:wild-type males in an overlapping generation trial design. Male release ratios of 1:1 resulted in cages where mosquitoes with at least one copy of the transgene fluctuated around 50%. In comparison, two of three cages in which the malaria-resistance genes were linked to a gene-drive system in an overlapping generation, single 1:1 release reached full introduction in 6–8 generations with a third cage at ~80% within the same time. Release ratios of 0.1:1 failed to establish the transgenes. A non-overlapping generation, single-release trial of the same gene-drive strain resulted in two of three cages reaching 100% introduction within 6–12 generations following a 1:1 transgenic:wild-type male release. Two of three cages with 0.33:1 transgenic:wild-type male single releases achieved full introduction in 13–16 generations. All populations exhibiting full introduction went extinct within three generations due to a significant load on females having disruptions of both copies of the target gene, kynurenine hydroxylase. While repeated releases of high-ratio (10:1) non-drive constructs could achieve full introduction, results from the 1:1 release ratios across all experimental designs favor the use of gene drive, both for efficiency and anticipated cost of the control programs. The experimental introduction of manipulated genes into insect species has a long history in basic genetics. Recent advances in genome editing technologies have spurred considerable effort to exploit these methodologies to provide genetic solutions to some of the worst medical and agricultural problems caused by insects. Insect population suppression and population modification approaches have been proposed to control transmission of vector-borne diseases, including malaria. We used small cage trials to explore the efficacy of non-drive and gene-drive releases to deliver anti-malarial effector genes to a vector mosquito, Anopheles stephensi. We show that both approaches can work to introduce genes to high percentages, but as expected, the gene-drive approaches were more efficient in that they needed only a single release with a much lower number of released insects. The gene-drive females in our studies exhibited a significant load that resulted in some cage populations going to extinction. Furthermore, the accumulation of drive-resistant target genes prevented full introduction of the transgenes in those cages that did not go extinct. While none of the strains evaluated here are proposed for open release, these laboratory cage trials reveal features that can be used to improve next-generation gene-drive strains for population modification.
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104
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Schmidt H, Lee Y, Collier TC, Hanemaaijer MJ, Kirstein OD, Ouledi A, Muleba M, Norris DE, Slatkin M, Cornel AJ, Lanzaro GC. Transcontinental dispersal of Anopheles gambiae occurred from West African origin via serial founder events. Commun Biol 2019; 2:473. [PMID: 31886413 PMCID: PMC6923408 DOI: 10.1038/s42003-019-0717-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Accepted: 11/28/2019] [Indexed: 01/20/2023] Open
Abstract
The mosquito Anopheles gambiae s.s. is distributed across most of sub-Saharan Africa and is of major scientific and public health interest for being an African malaria vector. Here we present population genomic analyses of 111 specimens sampled from west to east Africa, including the first whole genome sequences from oceanic islands, the Comoros. Genetic distances between populations of A. gambiae are discordant with geographic distances but are consistent with a stepwise migration scenario in which the species increases its range from west to east Africa through consecutive founder events over the last ~200,000 years. Geological barriers like the Congo River basin and the East African rift seem to play an important role in shaping this process. Moreover, we find a high degree of genetic isolation of populations on the Comoros, confirming the potential of these islands as candidate sites for potential field trials of genetically engineered mosquitoes for malaria control.
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Affiliation(s)
- Hanno Schmidt
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California - Davis, Davis, CA 95616 USA
| | - Yoosook Lee
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California - Davis, Davis, CA 95616 USA
| | - Travis C. Collier
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California - Davis, Davis, CA 95616 USA
| | - Mark J. Hanemaaijer
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California - Davis, Davis, CA 95616 USA
| | - Oscar D. Kirstein
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California - Davis, Davis, CA 95616 USA
| | - Ahmed Ouledi
- Université des Comores, Grande Comore, Union of the Comoros
| | | | - Douglas E. Norris
- The W. Harry Feinstone Department of Molecular Microbiology and Immunology, The Johns Hopkins Malaria Research Institute, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205 USA
| | - Montgomery Slatkin
- Department of Integrative Biology, University of California - Berkeley, Berkeley, CA 94720 USA
| | - Anthony J. Cornel
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California - Davis, Davis, CA 95616 USA
- Mosquito Control Research Laboratory, Department of Entomology and Nematology, University of California - Kearney Research and Extension Center, Parlier, CA 93648 USA
| | - Gregory C. Lanzaro
- Vector Genetics Laboratory, Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California - Davis, Davis, CA 95616 USA
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105
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Rosenthal PJ, John CC, Rabinovich NR. Malaria: How Are We Doing and How Can We Do Better? Am J Trop Med Hyg 2019; 100:239-241. [PMID: 30628572 PMCID: PMC6367613 DOI: 10.4269/ajtmh.18-0997] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Philip J Rosenthal
- Department of Medicine, University of California, San Francisco, San Francisco, California
| | - Chandy C John
- Department of Pediatrics, Indiana University, Indianapolis, Indiana
| | - N Regina Rabinovich
- Harvard T.H. Chan School of Public Health, Boston, Massachusetts.,ISIGlobal, Boston, Massachusetts
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106
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Schairer CE, Taitingfong R, Akbari OS, Bloss CS. A typology of community and stakeholder engagement based on documented examples in the field of novel vector control. PLoS Negl Trop Dis 2019; 13:e0007863. [PMID: 31765377 PMCID: PMC6901234 DOI: 10.1371/journal.pntd.0007863] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 12/09/2019] [Accepted: 10/21/2019] [Indexed: 01/17/2023] Open
Abstract
Background Despite broad consensus on the importance of community and stakeholder engagement (CSE) for guiding the development, regulation, field testing, and deployment of emerging vector control technologies (such as genetically engineered insects), the types of activities pursued have varied widely, as have the outcomes. We looked to previous CSE efforts for clarity about appropriate methods and goals. Our analysis yielded a typology of CSE, and related vocabulary, that describes distinctions that funders, organizers, and scholars should make when proposing or evaluating CSE. Methods We compiled available formal documentation of CSE projects, starting with projects mentioned in interviews with 17 key informants. Major features of these examples, including the initiators, target groups, timing, goals, and methods were identified using qualitative coding. Based on these examples, subcategories were developed for a subset of features and applied to the identified cases of CSE in the documents. Co-occurrence of subcategorized features was examined for patterns. Results We identified 14 documented examples CSE projects, which were comprised of 28 distinct CSE activities. We found no clear patterns with respect to timing. However, we found that grouping examples according to whether initiators or targets could enact the immediate desired outcome could help to clarify relationships between goals, methods, and targets. Conclusion Based on this analysis, we propose a typology that distinguishes three categories of CSE: engagement to inquire –where initiators are empowered to act on information collected through engagement with target groups; engagement to influence –where initiators engage to affect the actions of already-empowered target groups; and engagement to involve –where initiators engage to delegate authority to target groups. The proposed typology can serve as a guide for establishing the goals, identifying appropriate methods, and evaluating and reporting CSE projects by directing attention to important questions to be asked well before determining who to engage and how. Mosquito borne diseases, such as malaria and dengue, are major causes of illness and death worldwide. Furthermore, it is getting harder to control mosquitoes and other disease-carrying pests because global climate change is facilitating their spread to new areas, and over time, mosquitoes develop resistance to pesticides. Scientists are therefore developing new methods for controlling mosquito vectors using new gene editing tools. However, releasing genetically engineered insects into the environment is controversial. Many experts recommend that communities and stakeholders be consulted about if or how to use these new methods, but there are few guidelines for the best way to do this. We examined published accounts of community and stakeholder engagement pertaining to novel vector control and looked for patterns across these cases. We found that many efforts were not described in published sources, but those that were could be grouped into three categories: engagement to inquire, engagement to influence, and engagement to involve.
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Affiliation(s)
- Cynthia E. Schairer
- Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, CA, United States of America
- Department of Family Medicine and Public Health, School of Medicine, University of California, San Diego, La Jolla, CA, United States of America
| | - Riley Taitingfong
- Department of Communication, University of California, San Diego, La Jolla, CA, United States of America
| | - Omar S. Akbari
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, United States of America
- Tata Institute for Genetics and Society, University of California, San Diego, La Jolla, CA, United States of America
| | - Cinnamon S. Bloss
- Department of Psychiatry, School of Medicine, University of California, San Diego, La Jolla, CA, United States of America
- Department of Family Medicine and Public Health, School of Medicine, University of California, San Diego, La Jolla, CA, United States of America
- Center for Wireless and Population Health Systems, Calit2, University of California, San Diego La Jolla, CA, United States of America
- * E-mail:
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107
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Janjic A. Assisted Evolution in Astrobiology-Convergence of Ecology and Evolutionary Biology within the Context of Planetary Colonization. ASTROBIOLOGY 2019; 19:1410-1417. [PMID: 31657949 DOI: 10.1089/ast.2019.2061] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In ecology and conservation biology, the concept of assisted evolution aims at the optimization of the resilience of organisms and populations to changing environmental conditions. What has hardly been considered so far is that this concept is also relevant for future astrobiological research, since in artificial extraterrestrial habitats (e.g., plants and insects in martian greenhouses) novel environmental conditions will also affect the survival and performance of organisms. The question therefore arises whether and how space-relevant organisms can be artificially adapted to the desired circumstances in advance. Based on several adaptation and acclimatization strategies in wild ecosystems of Earth, I discuss which methods can be considered for assisted evolution in the context of astrobiological research. This includes enhanced selective breeding, induction of epigenetic inheritance, and genetic engineering, as well as possible problems of these applications. This short overview article aims to stimulate an emerging discussion as to whether humans, which are already prominent drivers of Earth's evolution, should consider such interventions for future planetary colonization as well.
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Affiliation(s)
- Aleksandar Janjic
- Technical University of Munich, School of Life Sciences Weihenstephan, Freising, Germany
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108
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Marshall JM, Raban RR, Kandul NP, Edula JR, León TM, Akbari OS. Winning the Tug-of-War Between Effector Gene Design and Pathogen Evolution in Vector Population Replacement Strategies. Front Genet 2019; 10:1072. [PMID: 31737050 PMCID: PMC6831721 DOI: 10.3389/fgene.2019.01072] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 10/07/2019] [Indexed: 12/19/2022] Open
Abstract
While efforts to control malaria with available tools have stagnated, and arbovirus outbreaks persist around the globe, the advent of clustered regularly interspaced short palindromic repeat (CRISPR)-based gene editing has provided exciting new opportunities for genetics-based strategies to control these diseases. In one such strategy, called "population replacement", mosquitoes, and other disease vectors are engineered with effector genes that render them unable to transmit pathogens. These effector genes can be linked to "gene drive" systems that can bias inheritance in their favor, providing novel opportunities to replace disease-susceptible vector populations with disease-refractory ones over the course of several generations. While promising for the control of vector-borne diseases on a wide scale, this sets up an evolutionary tug-of-war between the introduced effector genes and the pathogen. Here, we review the disease-refractory genes designed to date to target Plasmodium falciparum malaria transmitted by Anopheles gambiae, and arboviruses transmitted by Aedes aegypti, including dengue serotypes 2 and 3, chikungunya, and Zika viruses. We discuss resistance concerns for these effector genes, and genetic approaches to prevent parasite and viral escape variants. One general approach is to increase the evolutionary hurdle required for the pathogen to evolve resistance by attacking it at multiple sites in its genome and/or multiple stages of development. Another is to reduce the size of the pathogen population by other means, such as with vector control and antimalarial drugs. We discuss lessons learned from the evolution of resistance to antimalarial and antiviral drugs and implications for the management of resistance after its emergence. Finally, we discuss the target product profile for population replacement strategies for vector-borne disease control. This differs between early phase field trials and wide-scale disease control. In the latter case, the demands on effector gene efficacy are great; however, with new possibilities ushered in by CRISPR-based gene editing, and when combined with surveillance, monitoring, and rapid management of pathogen resistance, the odds are increasingly favoring effector genes in the upcoming evolutionary tug-of-war.
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Affiliation(s)
- John M. Marshall
- Division of Epidemiology and Biostatistics, School of Public Health, University of California, Berkeley, CA, United States
- Innovative Genomics Institute, Berkeley, CA, United States
| | - Robyn R. Raban
- Section of Cell and Developmental Biology, University of California, San Diego, CA, United States
| | - Nikolay P. Kandul
- Section of Cell and Developmental Biology, University of California, San Diego, CA, United States
| | - Jyotheeswara R. Edula
- Section of Cell and Developmental Biology, University of California, San Diego, CA, United States
| | - Tomás M. León
- Division of Epidemiology and Biostatistics, School of Public Health, University of California, Berkeley, CA, United States
| | - Omar S. Akbari
- Section of Cell and Developmental Biology, University of California, San Diego, CA, United States
- Tata Institute for Genetics and Society, University of California, San Diego, CA, United States
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109
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Teem JL, Ambali A, Glover B, Ouedraogo J, Makinde D, Roberts A. Problem formulation for gene drive mosquitoes designed to reduce malaria transmission in Africa: results from four regional consultations 2016-2018. Malar J 2019; 18:347. [PMID: 31615576 PMCID: PMC6794889 DOI: 10.1186/s12936-019-2978-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 09/26/2019] [Indexed: 01/10/2023] Open
Abstract
Background Gene drive mosquitoes have been proposed as a possible means to reduce the transmission of malaria in Africa. Because this technology has no prior use-history at this time, environmental risk assessments for gene drive mosquitoes will benefit from problem formulation—an organized and ordered process to identify protection goals and potential pathways to harm to the environment, or animal or human health. Recognizing this need, the New Partnership for Africa’s Development (NEPAD), with support from African and international partners, organized four regional consultative workshops in Africa to initiate this process. Methods The workshops were attended by a diverse set of participants and stakeholders, including scientists, ethicists, health professionals, government regulators in the fields of environment health and biosafety as well government policymakers, who met for 4 days to deliberate on protection goals and pathways relevant to the use of gene drive mosquitoes for malaria control. The goal of the workshops was not to produce a comprehensive and detailed environmental risk assessment of gene drive mosquitoes, but rather to introduce problem formulation as a tool to the stakeholder community, and to serve as a starting point for conducting systematic environmental risk assessments in the future, identifying protection goals related to gene drive mosquitoes that are particular to African stakeholders. Results Participants in the workshops frequently identified human health and biodiversity as being relevant broad protection goals. Results of the deliberations provide insight into the concerns of African participants at an early stage in the development of gene drive organism/products that should be instructive to developers using this technology. Conclusions In general, the African participants of the consultations had a precautionary perspective with regard to environmental risk assessment of gene drive technology. As gene drive technology develops, protection goals will become further refined and candidate products will be further defined. These workshops represent only the beginning of a continuing process that will ultimately inform environmental risk assessment for gene drive mosquitoes to control malaria in Africa.
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Affiliation(s)
- John L Teem
- ILSI Research Foundation, 740 Fifteenth Street NW, Suite 600, Washington, DC, 20005, USA
| | - Aggrey Ambali
- NEPAD Agency, Industrialization, Science, Technology and Innovation Hub, 230 15th Road, Midrand, South Africa
| | - Barbara Glover
- NEPAD Agency, Industrialization, Science, Technology and Innovation Hub, 230 15th Road, Midrand, South Africa
| | - Jeremy Ouedraogo
- ABNE, NEPAD Regional Office West Africa, Hann Maristes 2, Rue HB 350, BP 17204, Dakar, Senegal
| | - Diran Makinde
- NEPAD Agency, Industrialization, Science, Technology and Innovation Hub, 230 15th Road, Midrand, South Africa
| | - Andrew Roberts
- ILSI Research Foundation, 740 Fifteenth Street NW, Suite 600, Washington, DC, 20005, USA.
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110
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Feachem RGA, Chen I, Akbari O, Bertozzi-Villa A, Bhatt S, Binka F, Boni MF, Buckee C, Dieleman J, Dondorp A, Eapen A, Sekhri Feachem N, Filler S, Gething P, Gosling R, Haakenstad A, Harvard K, Hatefi A, Jamison D, Jones KE, Karema C, Kamwi RN, Lal A, Larson E, Lees M, Lobo NF, Micah AE, Moonen B, Newby G, Ning X, Pate M, Quiñones M, Roh M, Rolfe B, Shanks D, Singh B, Staley K, Tulloch J, Wegbreit J, Woo HJ, Mpanju-Shumbusho W. Malaria eradication within a generation: ambitious, achievable, and necessary. Lancet 2019; 394:1056-1112. [PMID: 31511196 DOI: 10.1016/s0140-6736(19)31139-0] [Citation(s) in RCA: 184] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 04/26/2019] [Accepted: 05/07/2019] [Indexed: 01/04/2023]
Affiliation(s)
- Richard G A Feachem
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Ingrid Chen
- Global Health Group, University of California San Francisco, San Francisco, CA, USA.
| | - Omar Akbari
- Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
| | - Amelia Bertozzi-Villa
- Malaria Atlas Project, University of Oxford, Oxford, UK; Institute for Disease Modeling, Bellevue, WA, USA
| | - Samir Bhatt
- Malaria Atlas Project, University of Oxford, Oxford, UK
| | - Fred Binka
- School of Public Health, University of Health and Allied Sciences, Ho, Ghana
| | - Maciej F Boni
- Center for Infectious Disease Dynamics, Department of Biology, Penn State, University Park, PA, USA
| | - Caroline Buckee
- Department of Epidemiology, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Joseph Dieleman
- Institute for Health Metrics, University of Washington, Seattle, WA, USA
| | - Arjen Dondorp
- Mahidol-Oxford Tropical Medicine Research Unit, Bangkok, Thailand
| | - Alex Eapen
- National Institute of Malaria Research, Chennai, India
| | - Neelam Sekhri Feachem
- Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Scott Filler
- The Global Fund to Fight AIDS, Tuberculosis and Malaria, Geneva, Switzerland
| | - Peter Gething
- Malaria Atlas Project, University of Oxford, Oxford, UK
| | - Roly Gosling
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Annie Haakenstad
- Institute for Health Metrics, University of Washington, Seattle, WA, USA
| | - Kelly Harvard
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Arian Hatefi
- Department of Medicine, University of California San Francisco, San Francisco, CA, USA
| | - Dean Jamison
- Institute for Global Health Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Kate E Jones
- Department of Genetics, Evolution and Environment, University College London, London, UK
| | | | | | - Altaf Lal
- Sun Pharma Industries, Mumbai, India
| | - Erika Larson
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Margaret Lees
- Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, San Francisco, CA, USA
| | - Neil F Lobo
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Angela E Micah
- Institute for Health Metrics, University of Washington, Seattle, WA, USA
| | - Bruno Moonen
- Bill & Melinda Gates Foundation, Seattle, WA, USA
| | - Gretchen Newby
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Xiao Ning
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, China
| | - Muhammad Pate
- Duke Global Health Institute, Duke University, Durham, NC, USA
| | - Martha Quiñones
- Department of Public Health, Universidad Nacional de Colombia, Bogota, Colombia
| | - Michelle Roh
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Ben Rolfe
- Asia Pacific Leaders Malaria Alliance, Singapore
| | | | - Balbir Singh
- Malaria Research Center, University Malaysia Sarawak, Sarawak, Malaysia
| | | | | | - Jennifer Wegbreit
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
| | - Hyun Ju Woo
- Global Health Group, University of California San Francisco, San Francisco, CA, USA
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Singh JA. Informed consent and community engagement in open field research: lessons for gene drive science. BMC Med Ethics 2019; 20:54. [PMID: 31351474 PMCID: PMC6660705 DOI: 10.1186/s12910-019-0389-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/09/2019] [Indexed: 11/30/2022] Open
Abstract
Background The development of the CRISPR/Cas9 gene editing system has generated new possibilities for the use of gene drive constructs to reduce or suppress mosquito populations to levels that do not support disease transmission. Despite this prospect, social resistance to genetically modified organisms remains high. Gene drive open field research thus raises important questions regarding what is owed to those who may not consent to such research, or those could be affected by the proposed research, but whose consent is not solicited. The precise circumstances under which informed consent must be obtained, and from whom, requires careful consideration. Furthermore, appropriate engagement processes should be central to any introduction of genetically modified mosquitos in proposed target settings. Discussion In this work, international guidance documents on informed consent and engagement are reviewed and applied to the genetically modified mosquito research context. Five analogous research endeavours that involve area-wide / open field experiments are reviewed. The approach of each in respect to the solicitation of individual informed consent and community engagement are highlighted. Conclusions While the solicitation of individual informed consent in host settings of gene drive field trials may not be possible or feasible in some instances, local community and stakeholder engagement will be key to building trust towards the proposed conduct of such research. In this regard, the approaches taken by investigators and sponsors of political science field research and weather modification field research should be avoided. Rather, proponents of gene drive field research should look to the Eliminate Dengue field trials, cluster randomised trials, and pragmatic clinical trials for guidance regarding how the solicitation of individual informed consent of host communities ought to be managed, and how these communities ought to be engaged.
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Affiliation(s)
- Jerome Amir Singh
- Centre for the AIDS Programme of Research in South Africa (CAPRISA), Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Durban, South Africa. .,Dalla Lana School of Public Health, University of Toronto, Toronto, Canada.
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113
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Devos Y, Craig W, Devlin RH, Ippolito A, Leggatt RA, Romeis J, Shaw R, Svendsen C, Topping CJ. Using problem formulation for fit-for-purpose pre-market environmental risk assessments of regulated stressors. EFSA J 2019; 17:e170708. [PMID: 32626445 PMCID: PMC7055725 DOI: 10.2903/j.efsa.2019.e170708] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Pre‐market/prospective environmental risk assessments (ERAs) contribute to risk analyses performed to facilitate decisions about the market introduction of regulated stressors. Robust ERAs begin with an explicit problem formulation, which involves among other steps: (1) formally devising plausible pathways to harm that describe how the deployment of a regulated stressor could be harmful; (2) formulating risk hypotheses about the likelihood and severity of such events; (3) identifying the information that will be useful to test the risk hypotheses; and (4) developing a plan to acquire new data for hypothesis testing should tests with existing information be insufficient for decision‐making. Here, we apply problem formulation to the assessment of possible adverse effects of RNA interference‐based insecticidal genetically modified (GM) plants, GM growth hormone coho salmon, gene drive‐modified mosquitoes and classical biological weed control agents on non‐target organisms in a prospective manner, and of neonicotinoid insecticides on bees in a retrospective manner. In addition, specific considerations for the problem formulation for the ERA of nanomaterials and for landscape‐scale population‐level ERAs are given. We argue that applying problem formulation to ERA maximises the usefulness of ERA studies for decision‐making, through an iterative process, because: (1) harm is defined explicitly from the start; (2) the construction of risk hypotheses is guided by policy rather than an exhaustive attempt to address any possible differences; (3) existing information is used effectively; (4) new data are collected with a clear purpose; (5) risk is characterised against well‐defined criteria of hypothesis corroboration or falsification; and (6) risk assessment conclusions can be communicated clearly. However, problem formulation is still often hindered by the absence of clear policy goals and decision‐making criteria (e.g. definition of protection goals and what constitutes harm) that are needed to guide the interpretation of scientific information. We therefore advocate further dialogue between risk assessors and risk managers to clarify how ERAs can address policy goals and decision‐making criteria. Ideally, this dialogue should take place for all classes of regulated stressors, as this can promote alignment and consistency on the desired level of protection and maximum tolerable impacts across regulated stressors.
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Affiliation(s)
- Yann Devos
- GMO Unit European Food Safety Authority (EFSA) Italy
| | - Wendy Craig
- Biosafety Group International Centre for Genetic Engineering & Biotechnology (ICGEB) Italy
| | | | | | | | - Jörg Romeis
- Research Division Agroecology and Environment Agroscope Switzerland
| | - Richard Shaw
- Centre for Agriculture and Biosciences International (CABI) United Kingdom
| | - Claus Svendsen
- Ecotoxicology and Chemical Risk Group United Kingdom Research and Innovation Centre for Ecology and Hydrology (CEH) United Kingdom
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114
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Resnik DB. Two unresolved issues in community engagement for field trials of genetically modified mosquitoes. Pathog Glob Health 2019; 113:238-245. [PMID: 31549925 PMCID: PMC6882470 DOI: 10.1080/20477724.2019.1670490] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
There is an emerging consensus among scientists, ethicists, and public health officials that substantive and effective engagement with communities and the wider public is required prior to releasing genetically modified mosquitoes into the environment. While there is little disagreement about the need for community and public engagement prior to releasing genetically modified mosquitoes into the environment, two important issues have not been resolved, namely: defining the community and dealing with potential conflicts between the community and the wider public. This commentary addresses these unresolved issues.
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Affiliation(s)
- David B. Resnik
- National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC, USA
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Ritchie SA, Staunton KM. Reflections from an old Queenslander: can rear and release strategies be the next great era of vector control? Proc Biol Sci 2019; 286:20190973. [PMID: 31238839 DOI: 10.1098/rspb.2019.0973] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
In this perspective, I discuss the great eras of vector control, centring on Aedes aegypti, the primary vector of dengue, Zika and several other viruses. Since the discovery and acceptance of the role of mosquitoes as vectors of disease agents, several significant strategies have been developed and deployed to control them and the diseases they transmit. Environmental management, insecticides and, to a lesser extent, biological control have emerged as great eras of vector control. In the past decade, the release of massive numbers of specifically modified mosquitoes that mate with wild populations has emerged as a significant new strategy to fight vector-borne diseases. These reared and released mosquitoes have been modified by the addition of a symbiont (e.g. Wolbachia bacteria), radiation or introduction of a genetic construct to either sterilize the wild mosquitoes they mate with, crashing the population, or to reduce the wild population's capacity to vector pathogens. Will these new rear and release strategies become the next great era of vector control? From my vantage point as a dengue control manager and researcher involved in two Wolbachia programmes, I will discuss the hurdles that rear and release programmes face to gain widespread acceptance and success.
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Affiliation(s)
- Scott A Ritchie
- 1 College of Public Health, Medical and Veterinary Sciences, James Cook University , Smithfield, Queensland 4878 , Australia.,2 Australian Institute of Tropical Health and Medicine, James Cook University , Smithfield, Queensland 4878 , Australia
| | - Kyran M Staunton
- 1 College of Public Health, Medical and Veterinary Sciences, James Cook University , Smithfield, Queensland 4878 , Australia.,2 Australian Institute of Tropical Health and Medicine, James Cook University , Smithfield, Queensland 4878 , Australia
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117
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Bartumeus F, Costa GB, Eritja R, Kelly AH, Finda M, Lezaun J, Okumu F, Quinlan MM, Thizy DC, Toé LP, Vaughan M. Sustainable innovation in vector control requires strong partnerships with communities. PLoS Negl Trop Dis 2019; 13:e0007204. [PMID: 31022178 PMCID: PMC6483154 DOI: 10.1371/journal.pntd.0007204] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Affiliation(s)
- Frederic Bartumeus
- CEAB-CSIC, Centre d’Estudis Avançats de Blanes, Girona, Spain
- CREAF, Centre de Recerca Ecològica i Aplicacions Forestals, Bellaterra, Spain
- ICREA, Institut Català de Recerca i Estudis Avançats, Barcelona, Spain
| | | | - Roger Eritja
- CREAF, Centre de Recerca Ecològica i Aplicacions Forestals, Bellaterra, Spain
| | - Ann H. Kelly
- Department of Global Health and Social Medicine, King’s College London, London, United Kingdom
| | | | - Javier Lezaun
- Institute for Science, Innovation and Society, University of Oxford, Oxford, United Kingdom
- * E-mail:
| | | | - M. Megan Quinlan
- Centre for Environmental Policy, Imperial College London, Ascot, United Kingdom
| | | | - Léa Paré Toé
- Institut de Recherche en Science de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Megan Vaughan
- Institute of Advanced Studies, University College London, London, United Kingdom
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118
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Hartley S, Thizy D, Ledingham K, Coulibaly M, Diabaté A, Dicko B, Diop S, Kayondo J, Namukwaya A, Nourou B, Paré Toé L. Knowledge engagement in gene drive research for malaria control. PLoS Negl Trop Dis 2019; 13:e0007233. [PMID: 31022169 PMCID: PMC6483158 DOI: 10.1371/journal.pntd.0007233] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Affiliation(s)
- Sarah Hartley
- Department of Science, Innovation, Technology and Entrepreneurship, University of Exeter, Exeter, United Kingdom
- * E-mail:
| | - Delphine Thizy
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Katie Ledingham
- Department of Science, Innovation, Technology and Entrepreneurship, University of Exeter, Exeter, United Kingdom
| | - Mamadou Coulibaly
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Abdoulaye Diabaté
- BioMedical Département, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Bakara Dicko
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Samba Diop
- Malaria Research and Training Center, University of Sciences, Techniques and Technologies of Bamako, Bamako, Mali
| | - Jonathan Kayondo
- Department of Entomology, Uganda Virus Research Institute, Entebbe, Uganda
| | - Annet Namukwaya
- Department of Entomology, Uganda Virus Research Institute, Entebbe, Uganda
| | - Barry Nourou
- Malaria and Neglected Tropical Diseases, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
| | - Léa Paré Toé
- BioMedical Département, Institut de Recherche en Sciences de la Santé, Bobo-Dioulasso, Burkina Faso
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119
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Promises and perils of gene drives: Navigating the communication of complex, post-normal science. Proc Natl Acad Sci U S A 2019; 116:7692-7697. [PMID: 30642954 DOI: 10.1073/pnas.1805874115] [Citation(s) in RCA: 66] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
In November of 2017, an interdisciplinary panel discussed the complexities of gene drive applications as part of the third Sackler Colloquium on "The Science of Science Communication." The panel brought together a social scientist, life scientist, and journalist to discuss the issue from each of their unique perspectives. This paper builds on the ideas and conversations from the session to provide a more nuanced discussion about the context surrounding responsible communication and decision-making for cases of post-normal science. Deciding to use gene drives to control and suppress pests will involve more than a technical assessment of the risks involved, and responsible decision-making regarding their use will require concerted efforts from multiple actors. We provide a review of gene drives and their potential applications, as well as the role of journalists in communicating the extent of uncertainties around specific projects. We also discuss the roles of public opinion and online environments in public engagement with scientific processes. We conclude with specific recommendations about how to address current challenges and foster more effective communication and decision-making for complex, post-normal issues, such as gene drives.
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120
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Brokowski C, Adli M. CRISPR Ethics: Moral Considerations for Applications of a Powerful Tool. J Mol Biol 2019; 431:88-101. [PMID: 29885329 PMCID: PMC6286228 DOI: 10.1016/j.jmb.2018.05.044] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 05/30/2018] [Accepted: 05/30/2018] [Indexed: 12/26/2022]
Abstract
With the emergence of CRISPR technology, targeted editing of a wide variety of genomes is no longer an abstract hypothetical, but occurs regularly. As application areas of CRISPR are exceeding beyond research and biomedical therapies, new and existing ethical concerns abound throughout the global community about the appropriate scope of the systems' use. Here we review fundamental ethical issues including the following: 1) the extent to which CRISPR use should be permitted; 2) access to CRISPR applications; 3) whether a regulatory framework(s) for clinical research involving human subjects might accommodate all types of human genome editing, including editing of the germline; and 4) whether international regulations governing inappropriate CRISPR utilization should be crafted and publicized. We conclude that moral decision making should evolve as the science of genomic engineering advances and hold that it would be reasonable for national and supranational legislatures to consider evidence-based regulation of certain CRISPR applications for the betterment of human health and progress.
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Affiliation(s)
- Carolyn Brokowski
- Department of Emergency Medicine, Yale School of Medicine, 464 Congress Avenue, New Haven, CT 06519-1362, USA
| | - Mazhar Adli
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, 1340 Jefferson Park Avenue, Charlottesville, VA 22908, USA.
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121
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Nash A, Urdaneta GM, Beaghton AK, Hoermann A, Papathanos PA, Christophides GK, Windbichler N. Integral gene drives for population replacement. Biol Open 2019; 8:bio037762. [PMID: 30498016 PMCID: PMC6361204 DOI: 10.1242/bio.037762] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 11/21/2018] [Indexed: 01/13/2023] Open
Abstract
A first generation of CRISPR-based gene drives has now been tested in the laboratory in a number of organisms, including malaria vector mosquitoes. Challenges for their use in the area-wide genetic control of vector-borne disease have been identified, including the development of target site resistance, their long-term efficacy in the field, their molecular complexity, and practical and legal limitations for field testing of both gene drive and coupled anti-pathogen traits. We have evaluated theoretically the concept of integral gene drive (IGD) as an alternative paradigm for population replacement. IGDs incorporate a minimal set of molecular components, including drive and anti-pathogen effector elements directly embedded within endogenous genes - an arrangement that in theory allows targeting functionally conserved coding sequences without disrupting their function. Autonomous and non-autonomous IGD strains could be generated, optimized, regulated and imported independently. We performed quantitative modeling comparing IGDs with classical replacement drives and show that selection for the function of the hijacked host gene can significantly reduce the establishment of resistant alleles in the population, while drive occurring at multiple genomic loci prolongs the duration of transmission blockage in the face of pre-existing target site variation. IGD thus has potential as a more durable and flexible population replacement strategy.
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Affiliation(s)
- Alexander Nash
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, South Kensington Campus, London SW7 2AZ, UK
| | - Giulia Mignini Urdaneta
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, South Kensington Campus, London SW7 2AZ, UK
| | - Andrea K Beaghton
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, South Kensington Campus, London SW7 2AZ, UK
| | - Astrid Hoermann
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, South Kensington Campus, London SW7 2AZ, UK
| | - Philippos Aris Papathanos
- Centre of Functional Genomics, Department of Experimental Medicine, University of Perugia, Perugia 06123, Italy
- Department of Entomology, Robert H. Smith Faculty of Agriculture, Food and Environment, Hebrew University of Jerusalem, Rehovot 7610001, Israel
| | - George K Christophides
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, South Kensington Campus, London SW7 2AZ, UK
| | - Nikolai Windbichler
- Department of Life Sciences, Imperial College London, Sir Alexander Fleming Building, South Kensington Campus, London SW7 2AZ, UK
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122
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Using Gene Drive Technologies to Control Vector-Borne Infectious Diseases. SUSTAINABILITY 2018. [DOI: 10.3390/su10124789] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
After years of success in reducing the global malaria burden, the World Health Organization (WHO) recently reported that progress has stalled. Over 90% of malaria deaths world-wide occurred in the WHO African Region. New tools are needed to regain momentum and further decrease the burden of malaria. Gene drive, an emerging technology that can enhance the inheritance of beneficial genes, offers potentially transformative solutions for overcoming these challenges. Gene drives may decrease disease transmission by interfering with the growth of the malaria parasite in the mosquito vector or reducing mosquito reproductive capacity. Like other emerging technologies, development of gene drive products faces technical and non-technical challenges and uncertainties. In 2018, to begin addressing such challenges, a multidisciplinary group of international experts published comprehensive recommendations for responsible testing and implementation of gene drive-modified mosquitoes to combat malaria in Sub-Saharan Africa. Considering requirements for containment, efficacy and safety testing, monitoring, stakeholder engagement and authorization, as well as policy and regulatory issues, the group concluded that gene drive products for malaria can be tested safely and ethically, but that this will require substantial coordination, planning, and capacity development. The group emphasized the importance of co-development and co-ownership of products by in-country scientists.
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123
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Yan Y, Finnigan GC. Development of a multi-locus CRISPR gene drive system in budding yeast. Sci Rep 2018; 8:17277. [PMID: 30467400 PMCID: PMC6250742 DOI: 10.1038/s41598-018-34909-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 10/26/2018] [Indexed: 12/11/2022] Open
Abstract
The discovery of CRISPR/Cas gene editing has allowed for major advances in many biomedical disciplines and basic research. One arrangement of this biotechnology, a nuclease-based gene drive, can rapidly deliver a genetic element through a given population and studies in fungi and metazoans have demonstrated the success of such a system. This methodology has the potential to control biological populations and contribute to eradication of insect-borne diseases, agricultural pests, and invasive species. However, there remain challenges in the design, optimization, and implementation of gene drives including concerns regarding biosafety, containment, and control/inhibition. Given the numerous gene drive arrangements possible, there is a growing need for more advanced designs. In this study, we use budding yeast to develop an artificial multi-locus gene drive system. Our minimal setup requires only a single copy of S. pyogenes Cas9 and three guide RNAs to propagate three gene drives. We demonstrate how this system could be used for targeted allele replacement of native genes and to suppress NHEJ repair systems by modifying DNA Ligase IV. A multi-locus gene drive configuration provides an expanded suite of options for complex attributes including pathway redundancy, combatting evolved resistance, and safeguards for control, inhibition, or reversal of drive action.
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Affiliation(s)
- Yao Yan
- Department of Biochemistry and Molecular Biophysics, Kansas State University, 141 Chalmers Hall, Manhattan, KS, 66506, USA
| | - Gregory C Finnigan
- Department of Biochemistry and Molecular Biophysics, Kansas State University, 141 Chalmers Hall, Manhattan, KS, 66506, USA.
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Carter SR, Warner CM. Trends in Synthetic Biology Applications, Tools, Industry, and Oversight and Their Security Implications. Health Secur 2018; 16:320-333. [PMID: 30339097 DOI: 10.1089/hs.2018.0067] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Recent developments in synthetic biology tools and techniques are driving commercialization of a wide range of products for human health, agriculture, environmental stewardship, and other purposes. This article reviews some of the trends in synthetic biology applications as well as some of the tools enabling these and future advances. These tools and capabilities are being developed in the context of a rapidly changing industry, which may have an impact on the rate and direction of progress. Final products are subject to a regulatory framework that is being challenged by the pace, scale, and novelty of this new era of biotechnology. This article includes discussion of these factors and how they may affect product design and the types of applications that are most likely to be supported and pursued commercially. The final section provides perspective on the security implications of these advances, with a focus on US interests.
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Affiliation(s)
- Sarah R Carter
- Sarah R. Carter, PhD, is a Principal at Science Policy Consulting, LLC, Arlington, Virginia. Christopher M. Warner, PhD, is a Research Biologist, US Army Corps , Environmental Lab, Vicksburg, Mississippi
| | - Christopher M Warner
- Sarah R. Carter, PhD, is a Principal at Science Policy Consulting, LLC, Arlington, Virginia. Christopher M. Warner, PhD, is a Research Biologist, US Army Corps , Environmental Lab, Vicksburg, Mississippi
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