Recent development of unique tools in genetic engineeringand synthetic biology have unlocked previously unimaginable power for theresearchers who wield them. The ethical and ecological implications of thesetools demand a careful examination of the abilities and dangers they present. HereI will examine both the capabilities of this technology, and the risks that itpresents. Are these genetic tools an apocalyptic disaster waiting to happen? Orare they a useful tool that conservationists can add to their collection?IntroductionThegenetic engineering of organisms is a rapidly growing field, with no shortageof environmental, ethical, and political controversy (Calloway 2016.
) Recentdevelopment of technologies such as CRiSPR/Cas9, and the gene-drive (Marcias,Ohm, & Rasgon 2017) raised yet more issues. Release of genetically-modifiedorganisms into the world at large has been seen as leading to potentialenvironmental or economic impacts. Potential dangers might include ecologicaldisequilibrium from the loss or sudden invasiveness of a species, (Rodriguez2016,) or agricultural ‘super-weeds’ which are resistant to common herbicides(Hoffman 1990.) If the use of genetically modified plants and animals are usedat all, the risk of accidental release and potential subsequent globalizationis virtually inevitable (Marcias 2017.) With this in mind, some applications ofrecent biotechnology have a remarkable capacity to be useful tools if released intentionally. Corletti(2017) suggests that invasive species could be combatted by breeding in adeleterious trait, potentially reducing the population or exterminating italtogether. Kalajdiz & Schetelig (2017) demonstrated that such amodification could be possible. They argue that sterilizing insects through gene-editingwould allow an environmentally friendly pest control method, where traditionalmethods had failed.
However this still requires the individual breeding andmodification of insect generations, as an infertility gene would be difficultto inherit. Hammond et al. (2015) offer a potential solution to thisheritability problem in their own quest to reduce transmission rates of malariamosquitoes. By introducing a haplosufficient female infertility gene, whichwould act recessively to only induce infertility in homozygote females, thegene could have a chance to propagate in a wild population. In addition tothis, they can make use of a gene-drive to induce hyper mendelian inheritance. Agene-drive is a system by which an ongoing and inheritable version of aCRiSPR/Cas9 gene insertion enzyme is included in the genome of the targetcreature itself.
This gene target germline cells, and effectively increaseinheritance from 50%, to close to 100%.Inaddition to fighting disease and combatting invasive species, another potentialuse for releasing gene-edited organisms into the wild is the field ofresurrection biology. This recent field seeks to chaperone the reintroductionof such species as the passenger pigeon, the Yangtze river dolphin, or even themoa and the wooly mammoth (Martinelli, Oksanen, & Siipi 2014.) Martinellicautions that the generation of these species, or species much like them, couldact as a reservoir for viruses that can be harmful to other animals. Additionally,as the environment has continued to change, the de-extinction of species couldlead to invasive behavior in what was once their normal environment. Martinellialso suggests that the ability to resurrect long dead species might diminishhumanity’s willingness to conserve existing species. Martinelli points out thatthe ethics of resurrection might not be limited to simply ecological harm, shereminds us that the Neanderthal genome has recently been fully sequenced (Greenet al. 2010.
)Allof these potential uses raise ethical questions of course, but none more sothen gene-drives themselves, leading to the fierce debates about their use(Calloway 2016.) In a recent United Nations biodiversity summit, a proposal fora complete moratorium on the use of gene-drives at all was narrowly defeated.Researchers claim that a moratorium would hurt efforts to reign in gene-drives,and prevent the opportunity to study them and understand their risks. Alternatesuggestions from experts in the field that oppose the moratorium, suggest amandatory registry of gene-drive experiments, or an isolated region where theymight be tested without risk. Geneticallymodified organisms in an agricultural sense do have an analog tohuman-influenced changes in agriculture. Many of the domesticated plants we useare highly modified versions of ancient strands. Despite the huge amount ofdomesticated crop plants, Ellistrand et al. (2010) were able to only findthirteen instances of an invasive plant from a domesticated ancestor, the vastmajority of these had undergone “de-domestication.
” Indicating that humanmeddling may change a plant, but the traits we add are not always asadvantageous in the context of the wild as we would imagine.Marcias(2017) notes that both CRiSPR and gene-drives are powerful technologies, wherehigh level of care must be used when working with them, but that major concernsraised about their use, such as off-target effects, are not issues that arelimited to these technologies alone. Corlett (2017) points out that the fiercebacklash against agricultural genetically modified organisms occurs despite theabsence of evidence that the risks are any greater than with other changes inagricultural practices. She acknowledge, that risks are greater and on a differentscale with gene edited animals as compared to plants. Finally,a recent paper indicates that the potential for unleashed gene-drives may notbe as serious a threat as once feared. Unckless et al (2017) shows strongevidence that modified organisms with a gene-drives carrying a negative traitwill inevitably develop a resistance to the gene-drive itself.
This was foundto occur in large populations quickly, and would extend even to smallerpopulations, as the gene-drive must effectively race an organism’s own repairmechanism with each use.Conclusion CRiSPR/Cas9 technology offers a powerful tool for the useof ecological conservation, but even without direct evidence that it is anymore dangerous than early forms of genetic change, such as breeding, radiation,or artificial selection, great caution must be used when working with thistool. Whether used to protect against a disease, eradicate a harmful invasivecreature, or bring back species once thought long-dead, this tool can be usedcarefully for great results, or it can be used with malice or ignorance, andcause a disaster.