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GM Mosquito Could Fight Malaria
qw0ntum writes "The BBC is reporting that a genetically modified (GM) variety of mosquitoes could be effective in combating the spread of malaria to humans. These GM insects carry a gene that prevents them from being infected by the malaria parasite and has the added benefit of providing a fitness advantage to the mosquitoes. From the article: 'In the laboratory, equal numbers of genetically modified and ordinary wild-type mosquitoes were allowed to feed on malaria-infected mice. As they reproduced, more of the GM, or transgenic, mosquitoes survived. According to the researchers, whose results appear in Proceedings of the National Academy of Sciences journal, after nine generations, 70% of the insects belonged to the malaria-resistant strain. [...] The modified mosquitoes had a higher survival rate and laid more eggs.' This has major implications for the billions of people living in areas with endemic malaria. The question in my mind, though, is what effects on the ecosystems of these areas will replacing an organism low on the food chain with a GM version? Between the news we saw last week and biomagnification, could this wind up substituting one problem for another?"
This is exactly what we need: mosquitoes that are more likely to survive longer. Now I need to go buy a better bug spray. Thanks, science!
www.timcoleman.com is a total waste of your time. Never go there.
Skinner: Well, I was wrong; the lizards are a godsend.
Lisa: But isn't that a bit short-sighted? What happens when we're overrun by lizards?
Skinner: No problem. We simply release wave after wave of Chinese needle snakes. They'll wipe out the lizards.
Lisa: But aren't the snakes even worse?
Skinner: Yes, but we're prepared for that. We've lined up a fabulous type of gorilla that thrives on snake meat.
Lisa: But then we're stuck with gorillas!
Skinner: No, that's the beautiful part. When wintertime rolls around, the gorillas simply freeze to death.
This is a really risky move. Sure, the mosquitoes are now immune to Malaria and will no longer carry it. But what if this immunity protects them from some other virus that is capable of surviving in the mosquito for longer? Now you have suddenly increased the mosquito population, made it harder to kill the population and made them carriers for some new pathogen that may be just as deadly as Malaria. Genetically modifying something that low on the food change can and will have dramatic effects on the rest of the environment. Why would we run that risk for a problem that can be handled through immunization and treatment? Sure, medical coverage sucks ass in the jungle, but things could get a lot worse if the new mosquitoes carry a new problem into all of the local villages.
-Rick
"Most people in the U.S. wouldn't know they live in a tyrannical state if it walked up and grabbed their junk." - MyFirs
There was an old lady who genetically modified a fly
I don't know why she modified a fly - perhaps she'll die!
There was an old lady who modified a spider,
That wriggled and wiggled and tiggled around her;
She modified the spider to catch the fly;
I don't know why she modified a fly - Perhaps she'll die!
There was an old lady who modified a bird;
How absurd to modify a bird.
She modified the bird to catch the spider,
She modified the spider to catch the fly;
I don't know why she modified a fly - Perhaps she'll die!
There was an old lady who modified a cat;
Fancy that to modify a cat!
She modified the cat to catch the bird,
She modified the bird to catch the spider,
She modified the spider to catch the fly;
I don't know why she modified a fly - Perhaps she'll die!
There was an old lady that modified a dog;
What a hog, to modify a dog;
She modified the dog to catch the cat,
She modified the cat to catch the bird,
She modified the bird to catch the spider,
She modified the spider to catch the fly;
I don't know why she modified a fly - Perhaps she'll die!
There was an old lady who modified a cow,
I don't know how she modified a cow;
She modified the cow to catch the dog,
She modified the dog to catch the cat,
She modified the cat to catch the bird,
She modified the bird to catch the spider,
She modified the spider to catch the fly;
I don't know why she modified a fly - Perhaps she'll die!
There was an old lady who modified a horse...
She's dead, of course!
The PNAS study shows an additional effect that isn't quite covered by the blurb above: heterozygous mosquitos (those with only one copy of the gene) are more fit than homozygous mosquitos (those with two copies). This means that there is pressure to retain a large number of heterozygous individuals, which means there will be a mixed population of transgenic and non-transgenic mosquitos. While this might help humans in the short run (a smaller fraction of the mosquitos you're bitten by would carry Plasmodium, the malaria parasite), in the long run it pretty much guarantees that people will still get malaria, and the malaria parasite will have lots of opportunities to develop resistance to the introduced gene.
So it's a nice idea--and it would be more effective than releasing low-fitness transgenic mosquitos--but it's not quite there yet.
As to fears of biomagnification, mosquitos generally don't deal with stress by producing toxic compounds (unlike plants, who only have that option), and the transgenic protein is a protein and hence digestable. So it's very unlikely that there would be anything to magnify. Instead of worrying about creating toxic mosquitos, we should make sure that when we actually hit Plasmodium with drugs and modified mosquitos and so on, that we make things so difficult for it that it really devastates its population. Otherwise, we're just conducting a transgenic-mosquito-resistant Plasmodium breeding experiment. (Plasmodium has already developed at least some resistance to most common anti-malarial drugs).
The only reason it hasn't been applied to malarial mosquitoes in Asia and Africa is that there are something like two dozen species to deal with, and each one would require its own entire eradication program and on a much larger scale (it turns out that Asia is really big). That's what's cool about this idea -- it's a slightly more subtle variant of what the US has been doing for decades now. It's just more targetted -- eliminating the particular genes that allows malaria to be carried rather than the entire insect. And it avoids the need to breed millions or billions of the bugs yourself and releasing them every year -- the insects do it all for you, as long as the new alleles really are favourable.
Very clever -- IF it actually works. Goodness knows the people in the third-world don't need to have Malaria keep kicking them while they're down. Any chance to reduce the size of Malaria's bootprint is definitely worth a serious look.
I think maybe you misunderstood. The only reason the GM mosquitoes survive better is because they do not have their health compromised by the malaria parasite. Specifically
"However, when both sets of insects were fed non-infected blood they competed equally well."
They aren't harder to kill.