Malaria-proof Mosquitoes?!?
This is some seriously cool shit. Entomologists and geneticists at the University of Arizona modified a single gene in the Anopheles stephensi mosquito in the hope of shortening its lifespan to the point where the malaria parasite would be unable to mature fully before the host died. Instead, they entirely blocked infection by Plasmodium falciparum, the primary human malaria parasite. They still don’t understand entirely why it worked (you can find the actual published data here), but by all accounts it sure seems to.
Malaria is one of those diseases that kills a million or so people each year, but because nearly all of those million people live in third-world countries not much gets done about it. Drug companies can’t make much profit from making a drug that only poor people would buy, so progress has been slow. In fact, most of the current efforts to fight malaria revolve around mosquito control rather than targeting the parasite. There’s some really cool research going on here at the University of Florida that revolves around designing pesticides that target the mosquitoes’ uniquely alkaline digestive system, theoretically leaving other insects, fish and humans (with our acidic digestive systems) unaffected.
But what good is this new Mutant Mosquito going to do, besides maybe inspiring the next SyFy channel original movie? It’s far too early to say anything for sure, but some of the articles I’ve read are excited about replacing wild mosquitoes with the mutant construct. This seems pretty unlikely to me, given that the mutation reduces the mosquito’s lifespan, and therefore its breeding window, by about 20%. That’s not going to compete successfully with the wild mosquitoes.
The other argument is the ‘What have we wrought?!?’ conundrum, which is what I really wanted to explore here. No one is seriously suggesting that we should introduce these new mosquitoes into the wild, but the potential to take a lab-created organism and replace an existing one with it is fraught with interesting moral and ethical questions.
First, can we really predict every possible outcome? What if something goes horribly wrong once the mosquitoes are released? Isn’t that what happened with the love bugs? Those stupid things are everywhere!
Ok, the story about the love bugs being created in a lab and accidentally released is amusing and all, but it’s a myth. We have snopes.com for a reason.
Plants are obviously not on the same scale as genetically modified insects, though. Insects can crawl and fly and spread themselves across the globe. Malaria isn’t the only disease spread by mosquitoes, either. West Nile Virus, Dengue Fever, Yellow Fever… it’s not difficult to imagine one of these monsters filling whatever gap was left by the elimination of malaria. Still, we have to look at the very real danger malaria presents. If replacing the wild mosquitoes with this construct was a viable option, would it be ethical not to do so? How do we weigh the million actual lives that are lost every year to this parasite against the potential harm it could cause? I don’t really have an answer to that, but I think it will be very interesting to watch the progress of transgenic crops in agriculture. Good or bad, the results of these forays into the genetic manipulation of our environment will likely set the precedent for the future.
This post is reprinted with the author’s permission.
Love bugs… My father once had a ‘nightmare’ about an insect that landed on his finger, latched on, and bit him every time he did or said something mean. Granted, I expect robotics to come up with curiosities like that before genetic engineering ever could, but either way I can only conceive of love bugs as a SyFy channel original movie. Some bizarre new form of pestilence, that…
But if mosquitos weren’t vital to the diets of other animals, I’d be happy to have them all engineered out of existence. Even bites that don’t infect you with a deadly parasite are super annoying. Heh.
Amanda, given my occupation and preoccupations, I think this is a terrific column. Crosses have happened naturally since the start of life, and whoever left offspring was deemed an evolutionary success. Humans started driving this process early, too, with domesticated plants animals (and ruling families). Contemporary genetic engineering is speeded up and directed, but otherwise does not introduce new concepts — only new variations.
One problem with human-driven genetic engineering is that we often force propagation of sub-species whose problems are not immediately apparent. Also, there is the access/stratification angle. The major reason that farmers were incensed at Monsanto was not because their seeds were engineered — but because they were engineered to be sterile in addition to their other tweaks, which meant that they had to buy them anew each year.
Bang-Up post I enjoyed it. Someone else once said: Fiction is about stuff that’s screwed up.