dissabte, 24 de setembre del 2016

Los mosquitos genéticamente modificados podrían acabar con los virus más mortales del mundo. Si les dejamos



The Aedes aegypti mosquito is a beautiful, brilliant killer.

Dark with white spots and a wingspan of only a few millimeters, it is smaller and stealthier than the mosquitoes that might keep you up at night, buzzing in your ear. There are thousands of species of mosquitoes, but only a few hundred are interested in humans. The Aedes aegypti is among the deadliest of them all.

The Aedes lives and breeds in places where people are, laying its eggs in a few droplets of stagnant water at the bottom of a forgotten beer can and then spending its short life hiding under beds and in closets. Its hardy eggs can survive months without water, waiting until conditions are just right to hatch. It bites legs and ankles, feeding quickly before it gets swatted away. It prefers small meals from many people, spreading disease with incredible efficiency as it goes.

Native to Africa, globalization has aided the Aedes‘ travels to nearly every continent, and with it, the proliferation of disease. It is the primary carrier of yellow fever, dengue fever, Zika virus and chikangunya. With the exception of yellow fever, these diseases do not have vaccines or cures. The Aedes assists in the killing of tens of thousands of people each year and infects many, many more. As its footprint has widened, our methods of fighting it have weakened. Insecticides are still our best form of defense, but Aedes aegypti have begun to develop resistance.

At long last, though, mankind may be on the verge of a mosquito-busting panacea. In August, faced with the Zika crisis, the Food and Drug Administration gave the green light to Oxitec, a British biotech company that aspires to release millions of genetically modified mosquitoes into the wilds of the Florida Keys. Oxitec has engineered male mosquitoes to turn the species against itself, giving them a lethal gene that kills off any offspring they might have with a wild female. The idea is to flood the local mosquito population with genetic mutants, until the wild population eventually dies out. In Key West, Oxitec hopes to assess how well the Frankenskeeters fare in the realm of Mother Nature.

Such innovations offer a dream of a world free from many of the ailments that plague it. But the Keys is not Oxitec’s first test site. It has similar projects underway in Brazil, Panama, India and the Cayman Islands. And others are also testing their own visions for disease-smiting killer mosquitoes. The Bill and Melinda Gates Foundation has invested $75 million in a plan to use a technology called gene drive to quash troublesome mosquito populations. Another company, MosquitoMate, has developed a mosquito that relies on a type of bacteria called Wolbachia to render them sterile. MosquitoMate has already begun trials in California. It recently received regulatory approval to expand them to Key West.

Such innovations offer a dream of a world free from many of the ailments that plague it. It could mean the end of malaria and dengue fever. It could mean crops free from pests and pesticides. It could offer a way to combat ecological damage wrought by insects showing up in places they do not belong.

What crushes that dream may be us. While at one point in history, genetic modification was a beacon for the future’s glittering possibility, today you can scarcely utter the words “genetic” and “modified” without causing a fuss.

Oxitec has faced opposition in all corners of the globe. In the Cayman Islands, the rollout of its mosquitoes was briefly delayed after anti-GMO activists took their fight to court. But nowhere has the resistance been stronger or more hostile than in the Florida Keys where local activism threatens to upend the whole thing.

As the pioneering synthetic biologist Jack Newman put it to me, “What stands between us and addressing one of the biggest public health issues in the world is not science. It’s how we talk about science.”

Absent a vaccine, Oxitec’s technology could be our most effective tool in fighting Zika. Genetically engineered mosquitoes could go a long way towards fighting some of the world’s deadliest viruses. The bigger question is whether we will let them.
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