Brazilians welcome genetically-modified mosquito to help fight dengue fever

http://www.pri.org/stories/2014-04-25/brazilians-welcome-genetically-modified-mosquito-help-fight-dengue-fever

by ojosilva • 12 years ago

139 86 12 years ago

pri.org

rjtavares• 12 years ago

Recent rabiolab episode on this subject: http://www.radiolab.org/story/kill-em-all/

Myztiq• 12 years ago

I came here just to post that link. Cheers.

jrkelly2• 12 years ago

One of the best new applications of GMOs. Interestingly, Rachel Carson mentioned this approach in Silent Spring: https://twitter.com/mem_somerville/status/457876443586760704...

Oxitec is making the mosquitoes via GM rather than mutation but approach is the same.

icegreentea• 12 years ago

A common fear when deploying systems like this is that we are somehow tampering with nature, and that given our inability to predict outcomes, we should therefore err to the side of caution.

I typically agree with this line of thought. However, in this particular context, something to strongly consider is that Aedes aegypti isn't native to South America. As implied by its name, it's native to Africa. We (humans) brought them over to New World as part of the Columbia Exchange (likely in a slave ship... along with malaria, and yellow fever, and the disease in question Dengue fever).

hrktb• 12 years ago

As mosquito related problems are just plain hard and in this context ther is no other viable solution, I also think the usual fear is less important in this context.

But for the sake of the argument, the fact that this mosquito comes from Africa doesn't really matter so much, as the consequences of this operation could go from making it immune to this gene, make it mutate in a different/worse direction, or have the engineered mosquitoes affect the environmenr in other unknown and not measurable ways.

eqdw2• 12 years ago

Where I'm from, the city routinely carpet-bombs the city with pesticides (http://en.wikipedia.org/wiki/Malathion). This is pretty contentious, especially since it's primarily for pest control and not actually for health reasons.

GMO tech that lets us stop breathing in all that delicious malathion is a good thing, in my books

Houshalter3• 12 years ago

I'm not sure if it's even possible to be "immune", but if it doesn't work oh well, nothing lost.

Changing the mosquitoes in any significant way is incredibly unlikely. Random mutations happen all the time in nature.

marcosdumay3• 12 years ago

Aedes aegypti is a domestic animal here. And we have no lack of moskitoes to fill their niche at Brazil (the best news being that most of them didn't evolve along humans, and are harmless).

It's worth looking at any biological alternative to the widespread use of insecticides.

jostmey• 12 years ago

The approach may work a while. But then I am sure some mutant gene will eventually emerge in the wild-type populations that will inhibit the synthetic kill gene. That's how Nature works.

Snail_Commando• 12 years ago

The approach may work a while. But then I am sure some mutant gene will eventually emerge in the wild-type populations that will inhibit the synthetic kill gene.
That's how Nature works.

More accurately, "That's how Nature works, sometimes."

The statement "...some mutant gene will eventually emerge ... that will inhibit [another gene]" describes one subset of the set of all possible causes of future genetic expression branching from this point. There is no law (that we are yet aware of) that allows us to say conclusively that a certain genetic trait will be selected for or against with any meaningful certainty. Furthermore, we have no scientific footing on which to say 'we are sure that a specific mutation will arise that will inhibit this other mutation' as decreed by Nature. In order for the claim to always be true in all arbitrary subsets of Nature, we would need to at least know: whether or not the gene will be selected against, specifically how the gene will be selected against, and nearly all nth order organism-local and population-global effects of a specific mutation or selection event. (We can play Nature in the lab and make approximations of the claim, though! Sort of.)

We can make statements like "If the oxygen content of that atmosphere or environment increases, it is possible that many anaerobic organisms will be selected against." Or, "If low hemoglobin production becomes advantageous, at some point after that, conditions x, y, and ... will likely exhibit reciprocal selective pressures."

Of course, we can also say things like, "All species are statistically likely to go extinct." (That's not very interesting.)

Essentially, we can make broad guesses about future states of genetic expression (and implied warranties and effects) under certain specific contexts. But we cannot say that a specific genetic cause and effect will occur as derived from an inherent property of Nature and a specific sub-state of the universe. As far as we know, genetics, mutation, evolution, and selection are just functions in a mostly random, iterated chaotic system that we are just beginning to comprehend.

We cannot say that 'a particular gene will be selected against, because it is inevitable that specific genes are invariably inhibited or selected against by subsequent shifts in population genetics.' In a sense, that's partially accurate. All species, and by extension, each gene and all genomes, are likely to be selected against. But not always via mutation. It's about the same as saying that species go extinct because of x; it's not certain to be true and may not yield any new information.

There is no law (that we know of) that allows us to make deterministic statements like 'X% of the genome will be inhibited because of the emergence of another mutation'.

For all we know, a rogue asteroid might hit Earth on Tuesday during rush hour in Hong Kong. Or, that particular gene may end up surviving until the closest possible moment before the heat death of the universe. On a more fundamental level, we'd need laws that allow us to predict specific future events (with interesting and meaningful degrees of certainty). We would need to be able to identify and map the exquisitely threaded chaos woven throughout Nature before we can be reasonably certain that 'a mutation will eventually arise to inhibit this other mutation.'

pistle• 12 years ago

Nature will find a way... until humans kill it. If we can eradicate some species we can eradicate them all - except those little tardigrade things. It's one thing to slowly evolve enhancements to slow pressures/opportunities in the environment. It's another whole thing to be able to withstand a quickly-emerging, severe bottleneck in your particular environment.

fixermark• 12 years ago

That's a pretty good prediction. Were I a betting man, my money would be on an explosion of females who can use some form of detection to suss out the defective gene based on some secondary characteristic. If those females can then evade mating with the altered males, their offspring would rapidly expand through the ecosystem (given that their niche would be cleared of in-species competitors).

Jury's out on whether this change could happen before the mosquito population falls below sustainable levels, though. Mosquitos breed rapidly, but they don't hold a candle to bacteria breeding rates and it takes a lot of generations for those to evolve resistance to each generation of antibacterials.

searine• 12 years ago

Which is exactly why no species ever goes extinct.

Oh wait...

argc• 12 years ago

I am not afraid of GM stuff, but does anyone else think this idea is potentially really dumb? What about everything that relies on these mosquitoes as a food source? I am not an expert... but trying to just kill off an entire species sounds like a TERRIBLE idea...

greenyoda• 12 years ago

And, as the article points out, killing off this one species may not even halt the spread of dengue fever:

"Then there’s the possibility that as Aedes aegypti mosquitos are killed off, other species will just take their place.

Phil Lounibous, an insect ecologist at the University of Florida, says getting rid of Aedes aegypti won’t necessarily solve the dengue problem.

'The so-called Asian Tiger mosquito is (also) very abundant all throughout Brazil,' Lounibous says, 'and it ... is also a vector of dengue.'"

gus_massa• 12 years ago

I’m not sure, but perhaps eradicating the Aedes aegypti is enough to prevent most of the dengue transmission.

And the Aedes albopictus (Tiger mosquito) is also a non native specie in Brazil, so it’s probably a good idea to eradicate it too, perhaps using the same method. http://en.wikipedia.org/wiki/Aedes_albopictus

marcosdumay3• 12 years ago

It's a big and slow mosquito, seems very badly adapted to here (but somehow, it spreads at cities).

Why, between several thousands of other species, do people keep pointing that this one will grow to fill the aegypti's niche?

ggreer• 12 years ago

The people behind this program aren't fools. They're experts who have given a lot of thought to this problem. Some basic points should alleviate your fears. First, the mosquito they're trying to eradicate is a non-native species. Second, said mosquito is the primary vector for Dengue fever, which infects hundreds of thousands and kills hundreds in Brazil every year. Even if this mosquito was native to South America, eradicating it would almost certainly help people.

It's interesting how support for this program decreases with distance from it. If this outbreak was happening in your country, hurting your family, killing your friends, I doubt you'd be so loath to support GM solutions.

A side note: 99.9% of all species that have ever existed have gone extinct. Nature is not some carefully-balanced system. It is chaos and suffering on a scale we cannot imagine. The majority of wild animals live in a state of constant hunger, pain, and disease. Those with sufficiently complex brains live in fear of predators. Speaking of predators: We would be horrified to watch a man vivisect an antelope, but we pay to watch documentaries of lions doing the same thing. Apparently animal cruelty is fine when it's done by other animals.

rdl3• 12 years ago

Scientists studied getting rid of all mosquitoes globally, and came to the conclusion it wouldn't have much of a negative impact (and a huge net positive for due ending malaria, dengue, etc.) Nothing eats exclusively mosquitoes, and those animals (birds) which do eat them could just switch to other insects, which generally are not in short supply.

http://www.nature.com/news/2010/100721/full/466432a.html

I'd do it in a second.

lovemenot• 12 years ago

> If this outbreak was happening in your country, hurting your family, killing your friends, I doubt you'd be so loath to support GM solutions.

That's an appeal to shame. It's true that people are generally selfish. And not only those in the developed world. It's also true that, when under physical duress, people can be made to support just about any immoral, illegal or just plain bad idea. Just because the majority of those opposing it are not the same people as those who most stand to benefit directly it does not follow that, in this case, using GM is fine.

thaumasiotes2• 12 years ago

First, the mosquito they're trying to eradicate is a non-native species.

I really don't get the environmentalist emphasis on the world being, and staying, the way god ordained it at the beginning of the universe. Mosquitoes have a generation time measured in weeks; for any practical purpose, there's no such thing as a non-native mosquito. Assuming a mosquito generation length of one month, and a human generation length of 25 years, we can see that a mosquito population that's been around for 5 years is the equivalent of a human one that's been around for 1500.

Trying to distinguish between "native" species and "non-native" species makes all the sense of distinguishing between "anthropogenic global warming" and "natural global warming". There's no point. A phenomenon is good, or it's bad; it's not bad just because you can finger a particular cause, it's not good just because things were that way 100 years ago, and it's not bad just because things were different 10 years ago. Judge by the effects.

Retric• 12 years ago

It's an invasive species which IMO changes things.

mixmastamyk• 12 years ago

I make an exception for the mosquito. Killing the whole species sounds like great idea.

salmonellaeater• 12 years ago

One effect of parasites and diseases is to increase diversity. If a species becomes too common, a disease or parasite targeting it can flourish, cutting back its numbers and allowing other species to take its place. Eradicating mosquitoes might have an unexpected effect like making the number of rats or some other vermin to explode.

blisterpeanuts3• 12 years ago

The aedes aegyptus is an invasive species in the Americas and should be eradicated.

There are about 3000 species of mosquitoes in the world, of which three bear deadly disease:

1. Anopheles (malaria, elephantiasis, and encephalitis)

2. Culex (encephalitis, elephantiasis, and West Nile virus)

3. Aedes (yellow fever, dengue, and encephalitis)

Asian Tiger mosquitoes are a subspecies of Aedes.

If we were to wipe out these three voracious breeds, the world would go on: flowers would continue to be pollinated, frogs and birds would continue to feed.

The risk of this type of eradication effort is not that we "upset the balance" but that we somehow create a resistant strain or mutation that is an even bigger problem, such as the Africanized honey bee fiasco. But that risk is relatively minor, since they're releasing sterile mosquitoes to end reproduction, not fertile ones designed to continue breeding.

There are a couple of hundred species that feed on blood; the rest don't. If we rid the world of all the blood sucking mosquito species, likely it would make little difference ecologically, and millions of lives would be saved and the quality of life for humans would increase. It's highly unlikely that we can do it, but we should at least try.

The naysayers have a rather weak case. I say, go for it. Nature is always in balance. Life is dynamic, not static; species come and go all the time, and always have done so.

marcosdumay3• 12 years ago

First, I'd like to point that those are gender, not species. Those together add to thousands of species, and you forgot at least about Lutzomyia.

That said, I completely agree that we should get rid of them. And think it's more likely than you stated, if we can extinguish so many species, it can't be so much harder to do it on purpose. Currently we are barely trying, with techniques from the earlier XX century.

Carioca• 12 years ago

Coincidentally, the Africanized honey bee fiasco started in Brazil.

brianbreslin3• 12 years ago

There was a national science foundation study a few years back that suggested if you removed ALL mosquitos from the earth, there were in nearly EVERY case alternative food supplies for animals that currently eat mosquitos.

http://blog.chron.com/sciguy/2010/07/scientists-go-ahead-kil...

PhasmaFelis• 12 years ago

What about everything that relies on these mosquitoes as a food source?

Nothing in the world relies on mosquitoes as a food source. Some insectivores will happily eat mosquitoes if they can get them, but mainly feed on other species.

Mosquitoes also play a role in pollination in some areas, but, again, all mosquito-pollinated plants are more reliably pollinated by other local insects.

hoodoof• 12 years ago

http://en.wikipedia.org/wiki/Cane_toad

rdl3• 12 years ago

I wish the GMO developers had initially focused on products which were end-user or publicly beneficial like this, vs. just raising yields or reducing pesticide use (which are end user and societally beneficial, but can be cast by opponents as economic arguments). Without the existing anti-GMO movement, GMO would have a much easier time getting adoption in cases where it's essentially unambiguously a win (like this one).

arjunnarayan• 12 years ago

"Just raising yields" has helped save millions of poor folk in third world countries from starvation. I'm not sure that pacifying first world leftist hippies should be the top PR priority of science.

rdl3• 12 years ago

Green revolution did, but that wasn't GMO. (Borlaug was probably one of the top 10 people of the 20th Century)

GMO is much more recent, and generally works on crops which are large and mechanized, which don't really exist in third world countries. The main beneficiaries to date of GMO have been soybeans and corn in the US. The stat I've seen is 5-10% gains in the 90s from GMO. (http://www.plantphysiol.org/content/124/3/923.full)

There probably are ways to use GMO which would work in non-mechanized farming, though.

gcb03• 12 years ago

most of the starvation in the world is because someone wants more profits along the way.

jrkelly2• 12 years ago

The very first commercial application of GMOs was recombinant insulin for diabetics. Followed by a slew of other drugs - GMOs now make 50% of drugs (all the protein ones). The agriculture applications came 5-10 years later as plants were harder to engineer than microbes.

a_bonobo2• 12 years ago

Other examples: The enzymes in washing powders are generally produced by GM bacteria, too, together with the chymosin needed for cheese production.

There used to be a GM-tomato called FLAVR SAVR about 15 years ago, which had direct benefits to end customers = the tomatoes stayed fresh longer. Public opposition out of fear killed it (also a good lesson: don't give flashy, technical names to food).

http://californiaagriculture.ucanr.edu/landingpage.cfm?artic...

eqdw2• 12 years ago

My girlfriend is diabetic. Her mom is pretty stereotypical anti-GMO hippie type. To me, the irony is delicious.

Course, then I realize that my girlfriend's mom is essentially anti- her living and it stops being funny

ekianjo2• 12 years ago

Yeah, for diabetics that was a major revolution. A simple explanation on how it is done here: http://www.iptv.org/exploremore/ge/what/insulin.cfm

Glargine is one of the key recombinant products out there.

kimonos• 12 years ago

Brilliant idea!

PauloManrique• 12 years ago

Lack of education and government actions on this route is the biggest cause of dengue here in Brazil.

People know they shouldn't keep water in old tyres, food plants, box of waters opened and stuff but they still do it.

brianbreslin3• 12 years ago

A similar trial was done in the Florida Keys 2 years ago. The genetically modified mosquitos (same company I believe), were able to reduce the mosquito population immensely. Key West if they didn't carpet bomb it with insecticides from the sky would be miserable.

[1]http://america.aljazeera.com/articles/2013/11/9/genetically-...

ekianjo2• 12 years ago

Note that the article makes it seem that the Dengue fever is fatal in most cases, but it certainly is NOT. Most of the time people who get it will recover within 10 days, even though they will be severely incapacitated during that period. Most people who actually die from Dengue are people who were already weakened by something else or older populations.

erkkie• 12 years ago

One of the problems with dengue is that once you've been infected with one strain, getting infected with another one is much more likely to have serious consequences. That's a problem for people who travel for example.

http://en.wikipedia.org/wiki/Dengue_fever It is not entirely clear why secondary infection with a different strain of dengue virus places people at risk of dengue hemorrhagic fever and dengue shock syndrome. The most widely accepted hypothesis is that of antibody-dependent enhancement (ADE). The exact mechanism behind ADE is unclear.

gcb03• 12 years ago

no they dont welcome it. it happens under they ignorant apathy. the region where that happens in brazil is our red neck equivalent.

some politician just choose to spend a few millions on a british company (and recive the usual 10% back under the table as consultancy in the next year or so) instead of spending half of that in social programs that would have a permanent outcome instead of this joke.

but since politics in those states are viewed like something magical and out of reach of the common folk, nobody cares

windsurfer• 12 years ago

Do you have any sources? I, for one, welcome our new self-destructing mosquito overlords.

gcb03• 12 years ago

No i don't have any source because those policies are not discussed BEFORE. they are ADVERTISED AFTER the fact.

which proves my point. ...but i'm sure Veja will write a piece saying how nice that solution is. Even though every single person studying it already commented that trying to kill the mosquito is idiotic.

jimworm3• 12 years ago

I've recently been thinking about the possibility of a genetic disease for mosquitoes, transmitted down male lines but killing only females of the same brood, with the intended result that a relatively small release of males can cause an extreme imbalance in the sex ratio and possibly the elimination of mosquitoes from an area.

The different mechanisms of mosquito sex determination aside, I haven't been able to work out something that might be feasible. Wondering if anybody else had similar ruminations, and if you'd share some of your thoughts?

danieltillett• 12 years ago

This has basically already been done using a bacteria called Wolbachia [0].

[0] http://www.eliminatedengue.com/our-research/wolbachia

jimworm3• 12 years ago

Thanks to your cue, I found a candidate gene that might fit the bill called Medea [0]. Wolbachia itself won't cause catastrophic sex-ratio imbalances, so does not cause a "White Plague" scenario.

[0] http://www.nature.com/scitable/blog/bio2.0/engineering_in_th...

robmcm• 12 years ago

This would only work for a while, and then, "nature would find a way".

Sometimes I think no one even bothered paying attention to Jurassic Park.

has2k12• 12 years ago

Nature does not always find a way, look at the fossil record for evidence.

jimworm3• 12 years ago

Humans have been very successful at beating evolution, if more by accident than purposeful action. Mosquitoes won't be pushovers like the dodo were, but if we eradicate one species of them they won't be the first insects we've driven extinct on purpose.

Houshalter3• 12 years ago

Not necessarily. Evolution isn't magic and lots of species go extinct. And evolution has never been optimizing for the survival of the species. It selects for individual fitness and sometimes even the fitness of individual genes.

Symmetry• 12 years ago

Once you start to get a sex imbalance then the genetics of future generations as a whole will disproportionately be determined by the female population, which won't have any copies of the gene. Eventually the gene will be eliminated from the population. It's the same principle that causes most species to produce equal number of males and females despite that not being ideal for the species as a whole.

Houshalter3• 12 years ago

Similar to a segregation-distorter. This occurs in some mice. The gene causes copies of itself to be present in all it's children by making them all one sex (male). The gene is highly selected for because it makes twice as many copies every generation than the alternative gene. And there is otherwise no difference between a male carrying the gene and one not carrying it.

If you released a gene like that on a species, soon there would be no females left and they would all die out.

riffraff2• 12 years ago

some time ago I read about a similar approach (used for malaria, I think) basically the GM mosquitoes have a "beak" too small for the plasmodium to get through and infect people.

Once they interbreed with the anopheles the mosquitoes basically stop being transmitters of malaria.

It seems slightly less likely to be something that comes back and bite us in the ass than eradicating a species from the ecosystem.

emeidi• 12 years ago

Unintended consequences, anyone? http://en.wikipedia.org/wiki/Unintended_consequences

E.g. Rabbits in Australia http://en.wikipedia.org/wiki/Rabbits_in_Australia#Biological...

danielweber• 12 years ago

Simply saying "unintended consequences" means doing nothing, ever.

WHO says "severe dengue is a leading cause of serious illness and death among children in some Asian and Latin American countries." After we don't have so many dead kids, some of them can grow up, and you can ask them how they feel about whatever unintended consequences there are.

fractallyte• 12 years ago

Anthropocentrism does not answer the question...

blisterpeanuts3• 12 years ago

There are always consequences, both intended and otherwise. It's best to go in with eyes open, having considered every possible consequence of our actions, and make a cost-benefit decision.

When human lives are at stake, notably the millions lost to malaria, dengue, and other mosquito-borne illnesses, the unintended consequences had better be pretty massive to make a difference.

johlindenbaum• 12 years ago

Somethine something, Hunger Games Tracker Jacker wasps.

Brazilians welcome genetically-modified mosquito to help fight dengue fever

Related Stories