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Editing the Wild



Article impact statement: Synthetic biology is being used to edit genomes of wild species for agriculture and human health. Conservation science must get involved. This article is protected by copyright. All rights reserved
Received: 26 January 2021 Revised: 18 March 2021 Accepted: 26 March 2021
DOI: 10.1111/cobi.13741
Editing the wild
William M. Adams1Kent H. Redford2
1University of Cambridge, Cambridge, UK
2Archipelago Consulting, Portland, Maine, USA
Kent H. Redford, Archipelago Consulting, Portland,ME 04112, USA.
Article impact statement: Synthetic biology is being used to edit genomes of wild species for ag riculture and human health. Conservation science must get involved.
A growing conservation science literature is exploring possi-
ble conservation applications of gene editing (e.g., Phelps et al.,
2019; Piaggio et al., 2016; Redford et al., 2019). Proposals
mainly focus on 2 approaches. First, to change the genomes
of species of conservation concern to enhance their ability to
survive threats like disease, for example, amphibians threatened
by chytrid fungus, or anthropogenic environmental changes, for
example, reef-building corals threatened by warming oceans.
Second, to change the genomes of species that threaten the sur-
vival of rare or endemic species, for example, invasive species
on oceanic islands.
Most discussion of conservation applications of gene edit-
ing is still more or less speculative, discussing the use of newly
developed tools and procedures or wishfully hoping for novel
solutions to intractable conservation problems. There is no seri-
ous funding available for such conservation applications, be
they blue-sky or practical. Development and application are
much more advanced in human health, veterinary science, and
agriculture, where gene editing is an increasingly mainstream
There are a small number of serious proposals for apply-
ing editing and related technologies to conservation problems,
suggesting that significant funding might become available. For
example, an international partnership is developing a gene drive
to rid oceanic island of invasive house mice (GBIRD, 2019).
There are also efforts to apply gene editing to de-extinction (e.g.,
Novak, 2018), although the conservation relevance of this strat-
egy is more speculative.
There is an extremely important debate to be had about the
application of gene editing in conservation (Redford & Adams,
2021). Risks and benefits are already being explored in the con-
servation science literature (e.g., Sandler, 2019), and in the inter-
national policy realm (e.g., Redford et al., 2019).
However, there is a significant blind spot in much of the dis-
cussion to date of possible conservation applications of syn-
thetic biology (whether advocating them or recommending that
they are not used). This relates to 2 assumptions: first, that the
genetic engineering of nondomesticated species is something
that may or may not happen in the future; second that those
decisions will be taken by conservation scientists and practition-
These assumptions have been an explicit or implicit feature of
meetings in which we have participated. They reflect profoundly
mistaken understanding. The question of whether wild species
(meaning those that are free to interact with other species out-
side of direct human control) should or should not be genet-
ically engineered is not something that might happen in the
future. It has already been done in a small number of cases and
is close to happening in several more. And decisions about those
deployments are not being informed by the views of conserva-
tion scientists at all.
The leading fields in which the genomes of free-living non-
domesticated species have been engineered are agriculture (pest
control) and public health (disease vector control). Genetically
engineered insects and other crop pests include pink boll worm
(Pectinophora gossypiella), fruit flies of various species (Drosophila),
and screwworm flies (Cochliomyia hominivorax). Experimental
releases of the diamondback moth (Plutella xylostella)have
already taken place in an experimental field in the American
state of New York––ecologically isolated, though not in a bio-
containment facility (Shelton et al., 2020).
Microbial species in the microbiomes of both insects and
plants are also being genetically modified to control agricul-
tural pests and enhance crop growth. Species in the honeybee
microbiome are being genetically modified to address colony
collapse disorder (Paxton, 2020). Microbes are being engineered
Conservation Biology. 2021;1–3. © 2021 Society for Conservation Biology
to promote their capacity to cause disease in wild agricultural
pests (Azizglu et al., 2020). Genetically modified microbes are
being developed for application in bioremediation and wastew-
ater plants (Dvorak et al., 2017). Microbes that are part of the
human microbiome are being engineered and will inevitably join
their wild relatives through leakage from human bodies.
Genetic engineering of wild species is also well advanced in
human public health. There is a significant investment in genet-
ically modifying mosquito vectors for malaria, dengue, and Zika
(Jones et al., 2021). In the case of Aedes aegypti, over a billion
genetically modified mosquitoes have been released in Brazil,
Panama, the Cayman Islands and release in Florida has been
approved (Oxitec, 2021).
Genetically modified fish are already in extensive production,
mostly in contained pens. But fish have escaped and in Norway
have bred with wild salmon and trout (Karlsson et al., 2016).
Genetically altered trees, so far poplar and eucalyptus, have also
been developed and planted (Chang et al., 2018).
Finally, though not wild species, gene-edited crop species
have been widely planted in an increasing number of countries.
The modified genomes in crop species are subject to evolution-
ary forces, including horizontal gene transfer and movement
into wild relatives or other plant species growing near agricul-
tural fields. Such movement across species boundaries appears
to be quite common (e.g., cotton, sunflower, rice, and papaya,
Vázquez-Barrios et al., 2021) leading to the reasonable assump-
tion that it will continue to happen with future genetically mod-
ified species.
The immediate ecosystems in which most of these interven-
tions have taken place are agricultural fields, forests, gardens,
or built-up areas. Some conservationists, tightly focused on the
protection of relatively undisturbed ecosystems globally, might
be tempted to dismiss genetic interventions in extensively trans-
formed ecosystems of this kind as unimportant. This would be
a mistake, for 3 reasons.
First, gene editing of free-moving species for agricultural or
health purposes will have biodiversity impacts (Redford et al.,
2019). Nature is not limited to the earth’s remining biodiverse
areas. Agricultural fields and other transformed habitats are also
ecosystems. They are connected ecologically and through gene
flow to other ecosystems, including some that are of the high-
est conservation importance. The release of organisms with
engineered genomes into unbounded spaces offers the risk of
spread, and gene introgression. Experiments in agriculture and
public health have ecological and conservation implications.
Second, the battles that are beginning on agricultural and
health applications to edit wild species will shape the land-
scape of funding, regulation, and public opinion when conser-
vation applications themselves are brought forward (Redford
& Adams, 2021). Nonconservation applications will create the
framework within which conservation applications will also be
judged by public opinion. Conservation does not exist in a bub-
ble. Debates about what is best for wild biodiversity will not
remain independent of public debates about the risks and ben-
efits of gene editing, particularly within the agriculture, biotech,
or pharmaceutical industries.
Third, the use of genetic engineering potentially undermines
conservation’s claim to be preserving nature. Conservation
practice is widely built on a distinction between naturalness (a
state of nature that needs to be protected, typically described
as “wild” or “pristine” nature) and artificiality (the impact of
human technologies and demands on the biosphere, from which
nature needs to be protected). Conservation already uses many
technologies to manage populations and ecosystems. Yet, as a
technology, genetic engineering is utterly novel. Its use to “save
nature” therefore potentially exposes conservation to popu-
lar understandings of genetic engineering as “unnatural.” Such
ideas, often using the emotive labels, such as “Frankenstein tech-
nologies” were important in environmentalist critiques of genet-
ically modified crops in the 1990s. Such ideas of the “unnatu-
ral” character of gene editing are potentially highly effective in
campaigning and are likely to shape public understanding of,
and reaction to, genetic engineering for conservation purposes
just as it will for commercial applications. Evidence for this can
already be found in some negative reaction to the use of genetic
engineering to create blight-resistant American Chestnut (Cas-
tanea dentata) by the insertion of a gene from wheat which pro-
duces an enzyme with antifungal properties (Newhouse & Pow-
ell, 2021; Smolker & Peterman, 2019;Taylor,2018).
Both supporters and detractors of gene editing of free-living
species, including “wild” or nondomesticated species, need to
recognize both that such releases have already taken place and
that more are planned as gene editing technology becomes
mainstream in fields like agriculture and human biology and
biotechnology. The scale and pace of the expansion of the syn-
thetic biology revolution globally (led by China and the United
States, but with many other countries following close behind) is
While the category of “conservation applications” or “con-
servation synthetic biology” may seem useful in debates in con-
servation journals and webinars, in practice, all genetic engineer-
ing of free-living species is important to the future of life on
Earth, and to the conservation organizations and scientists who
work to secure it. Nonconservation gene editing applications
may be taking place “off-stage” from a conservation perspec-
tive, but they will be critical in creating the framework and pub-
lic response within which conservationist applications will be
Conservation science has expanded its horizon repeatedly
in response to evolving understanding from within the disci-
pline as well as criticism from those outside. It has embraced
economics, psychology, and is engaging with anthropology and
political ecology. It has learned to open up to informed dis-
cussions of poverty, justice, and Indigenous and local cul-
tures. Now, it needs to expand again, to engage with the
wider debates about gene editing and synthetic biology. Genetic
technologies are transforming scientific fields and industries
from biotechnology and pharmaceutics to food production and
public health. Without doubt, they will also transform the natu-
ral world, both directly and indirectly. They may also transform
conservation practice in the years to come, and these changes
need careful, informed, and wide debate (Sandler, 2019).
Conservation scientists and practitioners urgently need to
develop the capacity and desire to understand the implications
of gene editing of free-living species, both those of conservation
concern and those that are not yet rare, and the impacts of gene
editing on both intact and human-transformed ecosystems.
Kent H. Redford
Azizglu, A. U., Jouzani, G. S., Yilmaz, N., Baz, E., & Ozkok, D. (2020). Genet-
ically modified entomopathogenic bacteria, recent developments, benefits
and impacts: A review. Science of the Total Environment,734, 139169.
Chang, S., et al. (2018). Genetic engineering of trees: Progress and new horizons.
In Vitro Cellular & Developmental Biology - Plant,54, 341–376.
Dvorak, P., Nikel, P. I., Damborsky, J., & de Lorenzo, V. (2017). Bioremedia-
tion 3.0: Engineering pollutant-removing bacteria in the times of systemic
biology. Biotechnology Advances,35, 845–866.
GBIRd. (2019). Retrieved from
Jones, R. T., Ant, T. H., Cameron, M. M., & Logan, J. G. (2021). Novel con-
trol strategies for mosquito-borne diseases. Philosphical Transactions of the Royal
Society B,376, 201909802.
Karlsson, S., Diserud, O. H., Fiske, P., & Hindar, K. (2016). Widespread genetic
introgression of escaped farmed Atlantic salmon in wild salmon population.
ICES Journal of Marine Science,73, 2488–2498.
Newhouse, A. E., & Powell, W. A. (2021). Intentional introgression of a blight
tolerance transgene to rescue the remnant population of American chestnut.
Conservation Science and Practice,2021, e348.
Novak, B. (2018). De-extinction. Genes,9(11), 548.
Oxitec Ltd. (2021). Public health. Retrieved from
Paxton, R. J. (2020). A microbiome silver bullet for honeybees. Science,367, 504–
Phelps, M. P., Seeb, L. W., & Seeb, J. E. (2019). Transforming ecology and con-
servation biology through genome editing. Conservation Biology,34, 54–65.
Piaggio, A. J., et al. (2016). Is it time for synthetic biodiversity conservation?
Trends in Ecology and Evolution,32, 97–107.
Redford, K. H., & Adams, W. M. (2021). Strange natures: Conservation in the era of
genome editing. New Haven, CT: Yale University Press.
Redford K.H, Brooks TM, Macfarlane NBW, Adams J S. (eds.) (2019). Genetic
frontiers for conservation: An assessment of synthetic biology and biodiversity conser vation.
Technical assessment. Gland, Switzerland: IUCN.
Sandler, R. (2019). The ethics of genetic engineering and gene drives in conser-
vation. Conservation Biology,34, 378–385.
Shelton, A. M., Long, S. J., Walker, A. S., Bolton, M., Collins, H. L., Revuelta, L.,
Johnson, L. M., & Morrison, N. I. (2020). First field release of a genetically
engineered, self-limiting agricultural pest insect: Evaluating its potential for
future crop protection. Frontiers in Bioengineering and Biotechnology,https://doi.
Smolker, R., & Petermann, A. (2019). Biotechnology for forest health? The test case of
the genetically engineered American Chestnut. The Campaign to STOP GE Trees.
Biofuelwatch and Global Justice Ecology Project. Buffalo, NY.
Taylor, S. (2018). GE Chestnut tree: ‘Trojan horse’ aimed at opening the
door to risky GM trees. Global Ecology Justice Project. Retrieved from
Vázquez-Barrios, V., Boege, K., Sosa-Fuentes, T., Rojas, P., & Wegier, A. (2021).
Ongoing ecological and evolutionary consequences by the presence of trans-
genes in a wild cotton population. Nature Scientific Reports,11, 1959.
How to cite this article: Adams WM. & Redford KH.
Editing the wild, Conservation Biology. 2021;13.
ResearchGate has not been able to resolve any citations for this publication.
Full-text available
After 25 years of genetically modified cotton cultivation in Mexico, gene flow between transgenic individuals and their wild relatives represents an opportunity for analysing the impacts of the presence of novel genes in ecological and evolutionary processes in natural conditions. We show comprehensive empirical evidence on the physiological, metabolic, and ecological effects of transgene introgression in wild cotton, Gossypium hirsutum. We report that the expression of both the cry and cp4-epsps genes in wild cotton under natural conditions altered extrafloral nectar inducibility and thus, its association with different ant species: the dominance of the defensive species Camponotus planatus in Bt plants, the presence of cp4-epsps without defence role of Monomorium ebeninum ants, and of the invasive species Paratrechina longicornis in wild plants without transgenes. Moreover, we found an increase in herbivore damage to cp4-epsps plants. Our results reveal the influence of transgene expression on native ecological interactions. These findings can be useful in the design of risk assessment methodologies for genetically modified organisms and the in situ conservation of G. hirsutum metapopulations.
Full-text available
In contrast to many current applications of biotechnology, the intended consequence of the American Chestnut Research & Restoration Project is to produce trees that are well‐adapted to thrive not just in confined fields or orchards, but throughout their natural range. Our primary focus is on disease tolerance, but we believe it will also be critically important that optimal restoration trees should have robust genetic diversity and resilience, which can be supplied by a full complement of their wild‐type genes. Chestnut restoration offers a unique case study because many restoration or intervention options have been attempted: doing nothing, planting non‐native chestnut species, planting hybrids, mutagenesis (exposing seeds to high levels of radiation to induce random mutations), backcross breeding, and now genetic engineering. Any of these techniques may be advantageous independently or in combinations, depending on the specific goals of land managers or restoration practitioners, but genetic engineering offers a unique opportunity to enhance blight tolerance while minimizing other changes to the genome.
Full-text available
Alternative, biologically-based approaches for pest management are sorely needed and one approach is to use genetically engineered insects. Herein we describe a series of integrated field, laboratory and modeling studies with the diamondback moth, Plutella xylostella, a serious global pest of crucifers. A “self-limiting” strain of Plutella xylostella (OX4319L), genetically engineered to allow the production of male-only cohorts of moths for field releases, was developed as a novel approach to protect crucifer crops. Wild-type females that mate with these self-limiting males will not produce viable female progeny. Our previous greenhouse studies demonstrated that releases of OX4319L males lead to suppression of the target pest population and dilution of insecticide-resistance genes. We report results of the first open-field release of a non-irradiated, genetically engineered self-limiting strain of an agricultural pest insect. In a series of mark-release-recapture field studies with co-releases of adult OX4319L males and wild-type counterparts, the dispersal, persistence and field survival of each strain were measured in a 2.83 ha cabbage field. In most cases, no differences were detected in these parameters. Overall, 97.8% of the wild-type males and 95.4% of the OX4319L males recaptured dispersed <35 m from the release point. The predicted persistence did not differ between strains regardless of release rate. With 95% confidence, 75% of OX4319L males released at a rate of 1,500 could be expected to live between 3.5 and 5.4 days and 95% of these males could be expected to be detected within 25.8–34.9 m from the release point. Moth strain had no effect on field survival but release rate did. Collectively, these results suggest similar field behavior of OX4319L males compared to its wild-type counterpart. Laboratory studies revealed no differences in mating competitiveness or intrinsic growth rates between the strains and small differences in longevity. Using results from these studies, mathematical models were developed that indicate release of OX4319L males should offer efficacious pest management of P. xylostella. Further field studies are recommended to demonstrate the potential for this self-limiting P. xylostella to provide pest suppression and resistance management benefits, as was previously demonstrated in greenhouse studies.
Technical Report
Full-text available
The IUCN Task Force on Synthetic Biology and Biodiversity Conservation and its accompanying Technical Subgroup were put together to accomplish the tasks laid out in Resolution WCC-2016-Res-086 from the 2016 World Conservation Congress. This Resolution (in part) called on the Director General and Commissions to undertake an assessment to: examine the organisms, components and products resulting from synthetic biology techniques and the impacts of their production and use, which may be beneficial or detrimental to the conservation and sustainable use of biological diversity and associated social, economic, cultural and ethical considerations… In addition, it called upon the Director General and Commissions with urgency to: assess the implications of Gene Drives and related techniques and their potential impacts on the conservation and sustainable use of biological diversity as well as equitable sharing of benefits arising from genetic resources… This assessment is the result of the work of the Technical Subgroup managed by the Task Force. Both the Task Force and the Technical Subgroup were established in January 2018
Nature almost everywhere survives on human terms. The distinction between what is natural and what is human-made, which has informed conservation for centuries, has become blurred. When scientists can reshape genes more or less at will, what does it mean to conserve nature? The tools of synthetic biology are changing the way we answer that question. Gene editing technology is already transforming the agriculture and biotechnology industries. What happens if synthetic biology is also used in conservation to control invasive species, fight wildlife disease, or even bring extinct species back from the dead? Conservation scientist Kent Redford and geographer Bill Adams turn to synthetic biology, ecological restoration, political ecology, and de-extinction studies and propose a thoroughly innovative vision for protecting nature. © 2021 by Kent H. Redford and William M. Adams. All rights reserved.
Mosquito-borne diseases are an increasing global health challenge, threatening over 40% of the world's population. Despite major advances in malaria control since 2000, recent progress has stalled. Additionally, the risk of Aedes -borne arboviruses is rapidly growing, with the unprecedented spread of dengue and chikungunya viruses, outbreaks of yellow fever and the 2015 epidemic of Zika virus in Latin America. To counteract this growing problem, diverse and innovative mosquito control technologies are currently under development. Conceptually, these span an impressive spectrum of approaches, from invasive transgene cassettes with the potential to crash mosquito populations or reduce the vectorial capacity of a population, to low-cost alterations in housing design that restrict mosquito entry. This themed issue will present articles providing insight into the breadth of mosquito control research, while demonstrating the requirement for an interdisciplinary approach. The issue will highlight mosquito control technologies at varying stages of development and includes both opinion pieces and research articles with laboratory and field-based data on control strategy development. This article is part of the theme issue ‘Novel control strategies for mosquito-borne diseases'.
A genetically engineered honey bee gut bacterium knocks down two major bee threats
The ethical issues associated with using genetic engineering and gene drives in conservation are typically described as consisting of risk assessment and management, public engagement and acceptance, opportunity costs, risk and benefit distributions, and oversight. These are important, but the ethical concerns extend beyond them because the use of genetic engineering has the potential to significantly alter the practices, concepts, and value commitments of conservation. I sought to elucidate the broader set of ethical issues connected with a potential genetic engineering turn in conservation and provide an approach to ethical analysis of novel conservation technologies. The primary rationales offered in support of using genetic engineering and gene drives in conservation are efficiency and necessity for achieving conservation goals. The instrumentalist ethical perspective associated with these rationales involves assessing novel technologies as a means to accomplish desired ends. For powerful emerging technologies the instrumentalist perspective needs to be complemented by a form-of-life perspective frequently applied in the philosophy of technology. The form-of-life perspective involves considering how novel technologies restructure the activities into which they are introduced. When the form-of-life perspective is applied to creative genetic engineering in conservation, it brings into focus a set of ethical issues, such as those associated with power, meaning, relationships, and values, that are not captured by the instrumentalist perspective. It also illuminates why the use of gene drives in conservation is so ethically and philosophically interesting. © 2019 Society for Conservation Biology.
As the conservation challenges of the planet increase, new approaches are needed to help combat losses in biodiversity and slow or reverse the decline of threatened species. Genome editing technology is changing the face of modern biology, facilitating applications that were unimaginable only a decade ago. The technology has the potential to make significant contributions to the fields of evolutionary biology, ecology, and conservation, yet the fear of unintended consequences from designer ecosystems containing engineered organisms has stifled innovation. To overcome this gap in the understanding of what genome editing is, and what its capabilities are, more research is needed to translate genome editing discoveries into tools for ecological research. We propose to enrich the debate by highlighting emerging and future genome editing technologies that have the potential to transform the environmental sciences, with the goal of expediting the implementation of new and creative uses for this powerful technology to enhance conservation of threatened species. This article is protected by copyright. All rights reserved