Image: Photograph by David Liittschwager
In Brief
- Scientists have genetically engineered mosquitoes with a self-destruct mechanism, an advance that could slow the spread of mosquito-borne diseases.
- One team of scientists has been conducting tests of the mosquitoes in cages in southern Mexico. Another has been releasing mosquitoes out into the wild.
- The intentional release of genetically modified insects has sparked international controversy, especially because the first releases were conducted in secret.
More In This Article
Outside Tapachula, Chiapas, Mexico—10 miles from Guatemala. To reach the cages, we follow the main highway out of town, driving past soy, cocoa, banana and lustrous dark-green mango plantations thriving in the rich volcanic soil. Past the tiny village of Rio Florido the road degenerates into an undulating dirt tract. We bump along on waves of baked mud until we reach a security checkpoint, guard at the ready. A sign posted on the barbed wire–enclosed compound pictures a mosquito flanked by a man and woman: Estos mosquitos genéticamente modificados requieren un manejo especial, it reads. We play by the rules.
Inside, cashew trees frame a cluster of gauzy mesh cages perched on a platform. The cages hold thousands of Aedes aegypti mosquitoes—the local species, smaller and quieter than the typical buzzing specimens found in the U.S. At 7 a.m., the scene looks ethereal: rays of sunlight filter through layers of mesh creating a glowing, yellow hue. Inside the cages, however, genetically modified mosquitoes are waging a death match against the locals, an attempted genocide-by-mating that has the potential to wipe out dengue fever, one of the world’s most troublesome, aggressive diseases.
This article was originally published with the title The Wipeout Gene.
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16 Comments
Add CommentEvery action has consensuses. If nothing else mosquitoes control Homo sapien populations, but there is more.
Reply | Report Abuse | Link to thisRead on..
http://www.madsci.org/posts/archives/2000-09/968278449.Gb.r.html
Fish survive in small ponds of still water eating mosquito larvae.
Mosquito larvae around here survive in small ponds of still water where there are no fish then they eat us.
Reply | Report Abuse | Link to thisReleasing genetically modified mosquitoes into the wild?!?
Reply | Report Abuse | Link to thisHANG ON!
Someone is forgetting that humans have evolved with mosquitoes over millions of years.
I am not against scientific advancement, however messing with a complex ecosystems is incredibly risky business.
This approach WILL have unintended, negative, consequences.
I live in Canada, at the fringes of the boreal forest, where we deal with mosquitoes every year. They are a pain. This year they were so bad, we could not spend time outdoors for about 8 of our short 12 week summer. However, those same mosquitoes feed millions of migrating songbirds every year. Even though we were directly affected by the mosquitoes this year, this is a trade-off I would never even consider making.
I understand that dengue fever and malaria are terrible diseases, and I thank goodness that I have never had to experience either. However, eradicating mosquitoes to solve these diseases is akin to having a surgeon use a sledge hammer to remove a brain tumor. It might remove the tumor, but there is nothing good about the final outcome.
The people doing this work, releasing these mosquitoes into the wild, need to think about what will happen to their rain forests when the birds no longer stop there, because there are no mosquitoes to eat.
This is tunnel vision at it's worst.
I started writing a reply to this, but then realized it's a troll post. Flagged for moderator removal. The scary thing is that there are real people out there who actually think this way. Fortunately few of them know how to use a computer.
Reply | Report Abuse | Link to thisSorry, that was in reply to Darnathe.
Reply | Report Abuse | Link to thisI'm really not doing well here, LOL! I meant that the above was in reply to scientific earthling, not Darnathe.
Reply | Report Abuse | Link to thisI think the whole "ecosystem in balance" is often overplayed. Life goes on to fill the vacuum left by a species that disappears. Most animals that eat mosquitoes and their larvae don't eat them exclusively. The world needs mosquitoes like it needs the AIDS virus.
Reply | Report Abuse | Link to thisThere is something seriously wrong with your brain. Humans are fully capable of self population control. Thanking God for nasty diseases is the worst kind of hipocracy. You are constantly wanting large numbers of us to die and yet you refuse to lead the way. Die already and provide that good example.
Reply | Report Abuse | Link to thisThose of us that are concerned by over population and are actually civilized will continue to work in simple ways to continue to spread technological civilization through out the world in order to promote self population control with out the brutality you promote.
Over the past 19 tears I have made 73 trips to Cuba from B.C. and have spent most of my time in the Niquero , Granma area. On my Nov. 2011 trip my fellow resort tourists and I experienced mosquito bite that were a great deal more severe than in previous years.
Reply | Report Abuse | Link to this? Has something gone wrong in the experiments ?
Gordon " Cubaking " Robinson
Port Alberni B.C. Canada
email abuc12@yahoo.ca
For pictures of the Granma area and my two Cuban Children :::
http://family.webshots.com/album/576092217QGmrIa
I think that I will most miss the bats.
Reply | Report Abuse | Link to thisThey aren't "eradicating mosquitoes". They are reducing the population of one particular species, Aedes aegypti, which feeds solely on humans, is responsible for spreading Dengue and is "not part of any significant food chain."
Reply | Report Abuse | Link to thisWhy bother commenting on something you clearly haven't read or understood?
Mosquitos genetically modified to be unable to reproduce have already been introduced in South America. This is VERY STUPID BAD HUMAN BAD!!
Reply | Report Abuse | Link to thisMosquitos are annoying, and they carry diseases, but they are ecologically irreplaceable. In my ecosystem, dragonflies eat them, frogs eat the dragonflies, snakes eat the dragonflies, and a large number of small and middle sized birds and mammals eat the snak...es. This is just one chain in the food-web that they help to form. The concept of an animal as a "pest," as being absolutely useless and only negative, is incomplete and destructive.
If you want songbirds, ducks, fish, turtles, and all of the fluffy animals.. you gotta accept the mosquitos.
I think there is room for responsible work in this area of GM pest and disease mitigation. However irresponsible companies like Oxitec need to be taken apart and the controlling individuals need to be prevented from all activities in their field. There need to be international penalties established and enforced for both corporations and individuals like those of Oxitec, whether successful or unsuccessful.
Reply | Report Abuse | Link to thisI was impressed with controls that did not occur to me, such as making the larva fluoresce to differentiate GM from natural mosquitoes, and being able to turn the effected gene off or on like a switch (in effect making a fail safe switch built in).
I also think that all GM experimentation should ensure that all the modified individuals die out within one, or a very few generations. The need for retreating locations or populations should be something that capitalists actually want to build into any model for business.
Only after prolonged re-treatment, and many trials without known adverse effects, should GM modifications permit permanent mutations in the wild.
And as to preceding comment(s) on this article, it is clear that this is not the only mosquito species that spreads the illness of dengue. The article states that the Asian Tiger mosquito can move in to repopulate and also spread dengue in the absence of A. aegypti.
Is this a joke or just inflammatory useless clowning around. The problem is that these off hand comments are taken seriously by people who don't know any better.
Reply | Report Abuse | Link to thisI have to agree with you. Assuming for the moment that only the targeted mosquito species could be wiped out, I say wipe it out. There are many mosquito species and the loss of one species will not do any long term harm. Get rid of it. The over hyped fears that people like to spread are no more real than giant radioactive ants. Bad things can happen but there is a limit to the scope of such consequences.
Reply | Report Abuse | Link to thisRead the article. The intent is not to wipe out all mosquitoes, just the one that carries disease. Did anyone in Canada DIE from the bites? Nobody is suggesting that ALL mosquitoes would be wiped out.
Reply | Report Abuse | Link to this