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Scientists Launch an Effort to Eradicate Malaria With Gene-Edited Mosquitoes

In a high-security lab in Italy, scientists have launched a large-scale experiment to genetically modify mosquitoes with an end goal of potentially eradicating malaria in Africa.

The mosquitoes have been gene-edited using the tool CRISPR, which allows scientists to make precise changes to strands of DNA. The mosquitoes carry a gene drive that will pass on certain traits to all of an organism's offspring and eventually impact the entire species. The specific modifications involved in this experiment impact female mosquitoes: They give them male mouths that prevent them from biting and spreading the malaria parasite, and they deform their reproductive organs so they can't lay eggs. As these genes spread throughout the population, more and more females will become sterile, drastically reducing or even killing off the entire population of malaria-spreading mosquitoes.

Given the unknowable but potentially disastrous impact of releasing gene-edited species into the natural world, such experiments must be done in controlled laboratory settings. Layers of security at this Italian lab prevent mosquitoes from getting out into the wild, but if one did manage to escape, it would not survive the local climate. The researchers hope to determine whether their "lethal modification" could be spread in the wild within six months to a year, but environmental experiments and political and social consultations will keep the mosquitoes' potential release at least five years away, researcher Tony Nolan, who helped develop the mosquitoes at Imperial College London, told NPR.

In June of 2018, Rowan Jacobsen took an in-depth look for Pacific Standard at the ethical dilemma that gene-editing technology has created in the scientific community in his story "Deleting a Species":

When any new technology arrives, the debate veers toward the best- and worst-case scenarios, the big dreams and the big fears. Gene drives are going to cure malaria. Gene drives are going to become bioweapons. That's our nature. But it's easy to forget how rarely the extremes come to be.

The real test will be after we have a few minor successes controlling diseases or agricultural pests with gene drive. Suddenly we will have one of the greatest hammers ever invented, and we will go looking for nails. Every fast-reproducing plant or animal whose behavior we don't like will be a candidate for redesign. Cockroaches that hate the scent of garbage. Poison ivy that doesn't cause a rash. Fire ants with no fire. There are loose nails everywhere that just need a few whacks to make our lives more comfortable.

"Why not?" goes the counterargument. We've been hammering nature for years. Pollution, habitat destruction, pesticides, insecticides, greenhouse gases. Yale doesn't convene an ethics panel every time somebody clear-cuts a forest or dynamites a reef to harvest the fish. Why is it different once genes are involved?

And yet it is.

Anyone who's ever taken the time to hike to the pristine valley or paddle to the uninhabited island knows the sublimity of finding oneself in a place where the agenda is non-human. It's a reminder that there are ways of being in the world that have little or nothing to do with human ways, patterns of existence that get us out of our own heads and expand the conversation of what it means to be a quivering coil of DNA on the third planet from the sun. It's a form of diversity, and every species is a kind of culture, a cohesive and elegant web of quirks, predilections, and traditions.

We've dammed Glen Canyon. We've littered Everest with ropes and oxygen tanks. Our pawmarks are all over even the wildest places. But we have yet to conquer the DNA of wild things. For the time being, that frontier has been visited by only a handful of early explorers.

The scientists running the experiment in Italy believe it will be a historic breakthrough.