Tag Archives: species extinction through bio-engineering

What You Can Do with $1 Million: Saving the New Zealand Parrot

Scientists in New Zealand have genetically sequenced every adult kakapo.  The kakapo, a cuddly bird that lives in New Zealand, is not designed for survival. Weighing up to 4kg, it is the world’s fattest and least flighty parrot. It mates only when the rimu tree is in fruit, which happens every few years.  It evolved in the absence of land-based predators, so instead of soaring above the trees it waddles haplessly across the dry forest floor below. When it stumbles across something that might kill it, it has the lamentable habit of standing still….Such oddities turned the kakapo into fast food for human settlers—and for the cats, rats and possums they brought with them. It seemed extinct by the 1970s, until scientists stumbled on two undiscovered populations in the country’s south. These survivors were eventually moved to small predator-free islands, where the Department of Conservation has spent decades trying to get them to breed…Its patience may finally be rewarded. The rimu was in fruit this year, and more than 80 chicks hatched after a bumper crop, making this the best breeding season on record. Many have survived into adolescence, increasing the number of adult kakapos by a third, to 200 birds.

But another threat to the kakapo is a lack of genetic diversity, because of low numbers and inbreeding. This is one reason why fewer than half of kakapo eggs hatch. By sequencing the genome of every living bird, scientists can identify closely related individuals and prevent more inbreeding by putting them on different islands. Well-matched birds cannot be forced to mate, but artificial insemination is also proving effective. Every bird is fitted with a transmitter to track its slightest movement. If a female mates with an “unsuitable” male, the process can be “overridden” with another bird’s semen. Time is of the essence, so drones are being used to whizz kakapo sperm to the right place.

All these efforts cost almost nz$2m ($1.3m) this breeding season. Yet the kakapo’s future still looks precarious. Earlier this year a fungal disease tore through the population. And tiny as the number of kakapos is, space is running out on the two islands where most of them live. New predator-free havens must soon be found. 

Excerpts from How eugenics is saving a pudgy parrot, Economist, Aug. 31, 2019

Eradicate Mosquitoes Forever: Gene Drives

The mosquitoes are being fitted with a piece of dna called a gene drive. Unlike the genes introduced into run-of-the-mill genetically modified organisms, gene drives do not just sit still once inserted into a chromosome. They actively spread themselves, thereby reaching more and more of the population with each generation. If their effect is damaging, they could in principle wipe out whole species.. If gene drives were to condemn to a similar fate the mosquitoes that spread malaria, a second of humankind’s great scourges might be consigned to history.

Gene drives can in principle be used against any creatures which reproduce sexually with short generations and aren’t too rooted to a single spot. The insects that spread leishmaniasis, Chagas disease, dengue fever, chikungunya, trypanosomiasis and Zika could all be potential targets. So could creatures which harm only humankind’s dominion, not people themselves. Biologists at the University of California, San Diego, have developed a gene-drive system for Drosophila suzukii, an Asian fruitfly which, as an invasive species, damages berry and fruit crops in America and Europe. Island Conservation, an international environmental ngo, thinks gene drives could offer a humane and effective way of reversing the damage done by invasive species such as rats and stoats to native ecosystems in New Zealand and Hawaii.

Such critics fear that the laudable aim of vastly reducing deaths from malaria—which the World Health Organisation puts at 445,000 a year, most of them children—will open the door to the use of gene drives for far less clear-cut benefits in ways that will entrench some interests, such as those of industrial farmers, at the expense of others. They also point to possible military applications: gene drives could in principle make creatures that used not to spread disease more dangerous… The ability to remove species by fiat—in effect, to get them to remove themselves—is, like the prospect of making new species from scratch, a power that goes beyond the past ambit of humankind.

Gene drives based on crispr-Cas9 could easily be engineered to target specific bits of the chromosome and insert themselves seamlessly into the gap, thus ensuring that every gamete gets a copy . By 2016, gene drives had been created in yeast, fruitflies and two species of mosquito. In work published in the journal Nature Biotechnology in September, Andrea Crisanti, Mr Burt and colleagues at Imperial showed that one of their gene drives could drive a small, caged population of the mosquito Anopheles gambiae to extinction—the first time a gene drive had shown itself capable of doing this. The next step is to try this in a larger caged population.

There are also worries about how gene drives might be used to create a weapon. …The need to find ways to guard against such attacks is one of the reasons that the Pentagon’s Defence Advanced Research Projects Agency (darpa) gives for its work on gene drives. Renee Wegrzyn, programme manager for darpa’s “Safe Genes” project, says the work is to prevent “technological surprise”, whether in the form of an unintended consequence or nefarious use. One of the academic teams she funds has made progress in developing anti-crispr enzyme systems that one day might be able to inhibit a drive’s operation.

Oversight needs not just to bring together a range of government agencies; it requires co-operation between governments, too. The Cartagena Protocol on Biosafety, which entered into force under the un Convention on Biological Diversity (cbd) in 2003, provides controls on the transfer of genetically modified organisms. But how it applies to gene drives is unclear—and besides, America has never ratified the convention. An attempt to ban gene-drive research through the cbd, which was backed by the etc Group and other ngos, failed at the convention’s biennial meeting in Cancún in 2016…Like the reintroduction of vanished species advocated by the rewilding movement, gene-drive technology will provide new arenas for the fight between those who wish to defend nature and those who wish to tame it.

Excerpts from Gene Drives: Extinction on Demand, Economist, Nov. 10, 2018, at 24

Meddling with Nature: Is it Right? Is it Fair?

Many envisioned environmental applications of newly developed gene-editing techniques such as CRISPR might provide profound benefits for ecosystems and society. But depending on the type and scale of the edit, gene-edited organisms intentionally released into the environment could also deliver off-target mutations, evolutionary resistance, ecological disturbance, and extinctions. Hence, there are ongoing conversations about the responsible application of CRISPR, especially relative to the limitations of current global governance structures to safeguard its use,   Largely missing from these conversations is attention to local communities in decision-making. Most policy discussions are instead occurring at the national or international level even though local communities will be the first to feel the context-dependent impacts of any release. ..

CRISPR gene editing and other related genetic technologies are groundbreaking in their ability to precisely and inexpensively alter the genome of any species. CRISPR-based gene drives hold particular import because they are designed to rapidly spread genetic changes—including detrimental traits such as infertility—through populations of sexually reproducing organisms, to potentially reach every member of a species. Villages in Burkina Faso are weighing the release of gene drive–bearing mosquitoes that could suppress malaria. Nantucket Island residents in the United States are considering the release of genetically engineered white-footed mice to deplete Lyme disease reservoirs. New Zealand communities are discussing the possibility of using genetic methods to eliminate exotic predators.

But what if a gene drive designed to suppress an invasive species escaped its release site and spread to a native population? Or if a coral species gene edited to better adapt to environmental stressors dominated reef ecosystems at the expense of a diversity of naturally evolving coral species and the fish that depend on them ? The gravity of these potential outcomes begs the question: Should humans even be meddling with the DNA of wild organisms? The absence of generally agreed on answers can be used to support calls for moratoria on developing and releasing genetically altered organisms, especially those with gene drives (6).

However, the promising benefits of environmental gene editing cannot be dismissed. Gene drives may provide a long-sought-after tool to control vectors of infectious disease and save millions of human lives. Projects to conserve ecosystems or promote species resilience are often intended to repair human-inflicted environmental damage. Put simply, either using this technology irresponsibly or not using it at all could prove damaging to humans, our welfare, and our planet.

At the international level, the Convention on Biological Diversity (CBD) has enlisted an expert technical panel to, in part, update its Cartagena Protocol (of which the United States is not a party) that oversees transboundary transport of living modified organisms to accommodate gene drive–bearing organisms. The International Union for the Conservation of Nature (IUCN) is also developing policy to address the release of gene-edited organisms. Although the CBD and the IUCN offer fora to engage diverse public feedback, a role largely fulfilled by civil society groups, none of these agencies currently use the broad and open deliberative process we advocate….

Different societal views about the human relationship to nature will therefore shape decision-making. Local community knowledge and perspectives must therefore be engaged to address these context-dependent, value-based considerations.  A special emphasis on local communities is also a matter of justice because the first and most closely affected individuals deserve a strong voice in the decision-making process…Compounding this challenge is that these decisions cannot be made in isolation. Organisms released into local environments may cross regional and even international borders. Hence, respect for and consideration of local knowledge and value systems are necessary, but insufficient, to anticipate the potentially ramifying global implications of environmental release of gene-edited organisms. What is needed is an approach that places great weight on local perspectives within a larger global vision…

The needs of ecosystems could also be given voice to inform deliberative outcomes through custodial human proxies. Inspired by legislative precedent set by New Zealand, in which the Whanganui River was granted legal “personhood,” human representatives, nominated by both an international body like the IUCN and the local community, would be responsible for upholding the health and interests of the ecosystems in question. Proposed gene-editing strategies would be placed in the larger context of alternative approaches to address the public health or environmental issue in question…

An online registry for all projects intending to release genetically engineered organisms into the environment must be created. Currently, no central database exists for environmental gene-editing applications or for decision-making outcomes associated with their deployment, and this potentially puts the global community at risk…A global coordination task force would be charged with coordinating multiple communities, nations, and regions to ensure successful deliberative outcomes. As a hypothetical example, genetic strategies to eliminate invasive possums from New Zealand must include representatives from Australia, the country likely to be affected should animals be transported outside the intended range. Similarly, the African Union is currently deliberating appropriate governance of gene drive–bearing mosquitoes to combat malaria on a regional scale. 

Excerpts from Natalie Kofl et al.,  Editing nature: Local roots of global governance, Science Magazine, Nov. 2, 2018