Eradicating mosquitos

Recently, there was some news about a technique to release GM-mosquitos to control Aedes aegypti. Is this technique actually being used in Brazil and in which parts?

A. aegypti is one of the main vectors of zika, among other diseases. A. albopictus (the tiger mosquito) is the other mosquito vector, but I don’t know if this technique has been modified to eradicate those.

GM mosquitoes from a company named Oxitecwere released in Cayman, a short walk from my house.

Further trials have been conducted or planned in the Florida Keys, Panama, and now Brazil.

Cayman has a very successful ongoing Mosquito Research Control Unit which helped evaluate the effectiveness of the GM release by providing accurate baseline data. The GM release reduced the Aedes aegypti mosquito population in the treated area by about 90%.

The initial project was successful enough that a larger release is in the planning stages. Nonetheless, some have criticized the release of GM mosquitoes despite, as one entomologist noted, "They have no argument that makes any sense.”

Thanks Iggy. I couldn’t remember the name Oxitec, so I didn’t have a good name to google for.

From their press release, it looks like they are just releasing them in the city of Piracicaba, but not in Rio where the Olympics are being held. Is that right?

They haven’t released them (yet), but THIS technology gets rid of the diseases without getting rid of the mosquitoes: https://www.technologyreview.com/s/543721/with-this-genetic-engineering-technology-theres-no-turning-back/

For some reason that link just takes me to the subscription renewal page, which is blank for me. Is there a word or name I can google to find out more?

It uses CRISPR technology, which is not what is usually meant by GMO. Usually GMO inserts a gene from another organism. CRISPR allows you to insert DNA sequences precisely. Combined with another technology called gene drive (which I don’t really understand) what it does is cause the new gene to spread through the entire population (of mosquitoes) since individuals with only one copy are sterile.

What I read about all this is that they have bred strains of mosquitoes that cannot carry malaria and are awaiting permission to release them. If they have made strains that cannot carry zika, I haven’t read about them, but perhaps they have.

I believe they were working on strains that couldn’t carry dengue fever, a close relative of zika. But there are four strains of dengue and you can get all four, so they want to make the mosquitoes immune to all of them.

As mentioned above, this technology does not reduce the incidence of mosquitoes, only renders them incapable of carrying that particular disease.

try this one:

there is no reason why they can’t use the technology to wipe out all diseases carried by mosquitoes without worrying about the ecological effects of wiping out mosquitoes.

OK, gene drive. Thought that’s what it was. Not sure it’s ready for prime time though. Besides which, not eradicating mosquitos is a drawback in my opinion…

http://www.fda.gov/AnimalVeterinary/NewsEvents/CVMUpdates/ucm490246.htm

Started a similar thread in MPSIMS. Thought this may apply

Do I have to post this every time this subject comes up?

GM Mosquitoes

Not for my sake. I read it the first time you posted it. What I wanted to know was what the current status was on its actual use in the field. Are they going to use it at the Rio Games or what?

They are currently being released in Brazil.

Yes, I know that now. They’ve been releasing them in this one small town named Piracicaba for about a year now. And from what I can tell, they’re going to expand the release to the area around the town soon, if they haven’t already.

But Brazil is a large country and that town is near São Paulo, not Rio. Are they planning on expanding the release area even more to include Rio and other Olympic venues?

BTW, you have to be careful googling on this. There are conspiracy web sites out there that actually blame zika on the Oxitec mosquitos. These people have no clue what they’re talking about.

Correction. Piracicaba is not a small town, but rather a good-sized city. But they’ve been releasing the mosquitos in a small part of that town, which area has only a few thousand people. The expanded release area looks like it will cover the entire city.

There seem to be two technologies here. If I have understood correctly, the one mozchron works on would destroy the mosquito population, with whatever ecological changes that might bring about, while the one with CRISPR/gene drive would only render them incapable of carrying the disease, but leave the population unchanged.

Two caveats: what would the ecological effect of destroying the mosquito population? Probably not much, it effects only one species and others would doubtless replace them. The other is, how do we know that whatever the CRISPR changes have any other effect, e.g. make it easier to carry other diseases? Seems unlikely, but who knows.

Either technology cannot be called back, once put in motion. At least Monsanto (for its own pecuniary purposes) has rendered its GMO seeds incapable of reproducing.

The Oxitec process (RIDL) results in the affected mosquitoes dying out. To that end it is self-limiting.

The gene drive approach is much scarier, since it has the potential to permanently alter the mosquito population. The intention is good. It would be great if the only change is to eliminate the vector’s ability to host malaria, dengue, or whatever; however, it is unpredictable what else might happen. The proponents of gene drive have proposed safeguards that would allow them to reverse the process, but this is really playing with fire. CRISPR is not precise, it always includes off-target effects. With gene drive you are deliberately installing a mechanism to alter the evolution of the pathogen vector, with unpredictable results.

We humans have repeatedly underestimated our ability to mess up ecosystems and overestimated our ability to predict in advance what might happen. I am all in favor of the RIDL methods, since the traits decay by a factor of two with each generation. Given the infancy of CRISPR/Cas9 and gene-drive technology in general, I hope we proceed with extreme caution.

[QUOTE=JWT

We humans have repeatedly underestimated our ability to mess up ecosystems and overestimated our ability to predict in advance what might happen. I am all in favor of the RIDL methods, since the traits decay by a factor of two with each generation. Given the infancy of CRISPR/Cas9 and gene-drive technology in general, I hope we proceed with extreme caution.[/QUOTE]

**Is GM something you work with as well?

I have a friend who’s mother is a retired Monsanto scientist of some sort. She has made the same statement you have.

She was going to move to Palm Beach this year but has decided against it. LOL**

Considering that the species in question is not native to the New World (it’s an introduction from Africa), I have no problem with completely eradicating it in Brazil or the US or anywhere else outside Africa.

No, but I follow it with some interest and I’ve heard Kevin Esveldt speak about gene drive.