Salvor.Hardin
Banned
The Wipeout Gene
A new breed of genetically modified mosquitoes carries a gene that cripples its own offspring. They could crush native mosquito populations and block the spread of disease. And they are already in the air—though that's been a secret
The technology marks the first time scientists have genetically engineered an organism to specifically wipe out a native population to block disease transmission. If the modified mosquitoes triumph, then releasing them in dengue-endemic zones worldwide could prevent tens of millions of people from suffering. Yet opponents of the plan warn of unintended consequences—even if mosquitoes are the intended victims.
Researchers also struggle with how to test their creations. No international laws or agencies exist to police trials of new transgenic organisms. For the most part, scientists and biotech companies can do what they want—even performing uncontrolled releases of test organisms in developing countries, neither warning the residents that their backyards are about to become a de facto biocolonialist field laboratory nor gaining their consent.
When a genetically modified male mosquito mates with a wild female, he passes his engineered genes to the offspring. The females—the biters—don’t survive long. When they emerge from the pupal stage, they sit motionless on the water. They won’t fly, mate or spread disease. The male progeny, in contrast, will live to spread their filicidal seed.
To kill female mosquitoes—the ones that suck blood and spread disease—James needed to hijack a genetic region that only females make use of. In 2002 James and Alphey identified a naturally occurring switch that controls flight-muscle development in females. Turn it off, and flight muscles won’t develop. Female mosquitoes emerging from the pupal stage just squat on the water’s surface, flightless, unable to attract mates. It was the perfect target.
Alphey founded Oxitec in 2002 to capitalize on the technology. In 2005 the Foundation for the National Institutes of Health, funded in large part by the Bill & Melinda Gates Foundation, granted James $20 million to test genetic strategies against dengue. James gave Oxitec $5 million to build the mosquitoes.
Source: http://www.scientificamerican.com/article.cfm?id=the-wipeout-geneThe collaborators designed a stretch of DNA that included a handful of genes and the regulatory switches needed to turn them on and off at the correct time. The system works like a relay team. During the mosquito’s metamorphosis from larva to adult, the female-specific switch flips on, activating the first gene, which produces a protein. This protein activates a second switch that kicks on gene number two, which then manufactures a toxin that destroys the female’s flight muscles. The researchers also added genes for fluorescent proteins that make modified larvae glow red and green, allowing them to monitor the spread of the genes through the population.
To breed large populations of a mosquito that they had explicitly programmed to die, Alphey and James needed a way to protect the females from the toxic gene cassette until after they reproduced. The trick was lacing the water with an antidote—the antibiotic tetracycline, which blocks production of the flight muscle–destroying protein. This design is also an emergency fail-safe: if a few of these genetically modified mosquitoes escape, they cannot reproduce without the drug.
Goddamn. I love the future. I do wonder what kind of unintended consequences could spring from this.