On the other hand, in the transcript of the interview, Besansky says “only male mosquitoes take a blood meal from their hosts”. Which made me think WTF? And sure enough there’s a disclaimer at the bottom of the transcript:
[POST-BROADCAST CORRECTION: In the original audio version of this story, Professor Besansky said only male mosquitoes take a blood meal from their hosts. In fact, it’s females mosquitoes that take the blood meal.]
How much can you trust a supposed ‘mosquito expert’ who gets their facts that wrong? I’m guessing maybe the janitor was cleaning the real Professor Besansky’s office and picked up the ringing phone on a lark.
Its quite obviously just a misspeak - talking to the media can be difficult. I know Nora quite well (friends for more than 20 years) - she’s one of the most knowledgable and prolific mosquito researchers working today, and a member of the National Academy of Sciences.
I think this is the key, because if all the offspring are sterile, then the non-sterile version would eventually rebound in future generations.
It would make sense if it’s true that the males are not sterile, because if the species can’t reproduce at all, then how would they get 750 million of them?
The lethal gene is tetracycline-repressible. You add tetracycline to the breeding water when rearing them in the lab and they develop normally for mass rearing. When released they’re not exposed to tetracycline and the lethal gene turns on.
Sorry, didn’t mean to insult your friend. I suppose I was being too snarky. I would probably misspeak a lot more than she did if I was to give a national radio interview.
Wasn’t there a similar trial being done with mice on Martha’s Vineyard? How did that end up?
Eta: it looks like they aren’t trying to wipe out the mice, just introduce immunity to carrying Lyme disease, and the genes involved all come from the same mouse species:
The mouse trial was never done, and I have serious doubts that it will ever be performed. The authors are at the MIT Media lab who are great at self promotion, public relations, and fundraising but who are less good at actually doing the work.
We have no gene drive developed or optimized in mice. We have no effector molecules that can be expressed in mice to block Borellia transmission to ticks. And it is unlikely that regulatory approval would ever be given to do it even if the technical hurdles could be overcome. It’s the GMO equivalent of vaporware. And mice aren’t the only vertebrate hosts for the bacteria, so even if it went forward its not clear that it would eliminate Lyme.
Müller and her colleagues decided to use CRISPR, a technique that enables scientists to make precise changes in DNA easily to genetically modify the Anopheles gambiae species of mosquito, which spreads malaria in sub-Saharan Africa.
The modification consisted of a mutation in a gene known as “doublesex,” which female mosquitoes need for normal development. The mutation deforms their mouths, making them unable to bite and spread the parasite. It also deforms their reproductive organs, rendering them unable to lay eggs.
Seems like a good process and outcome to me, but there is always that law of unintended consequences. I am not sure what will satisfy those opposed to this sort of thing short of not doing anything at all.
I should first say, the strategy in this new paper is not the same as the strategy in the OP. This thread started with transgenic sterile mosquitoes. This new paper is gene drive female lethality. Both population suppression, but 2 very different things.
This same group in this new paper (the Crisanti lab in the UK) has been doing this for the last several years. The mosquito strain used in the study was already developed and published. The main difference in this paper is instead of doing small cage experiments they used large laboratory population cages with lots of mosquitoes (for a lab study) and overlapping generations.
The next step will probably be using something called a “mosquitosphere”, which is essentially a very large cage in the open environment rather than a laboratory.
Then maybe a field release?
In short, this is an interesting paper but it’s not a “groundbreaking advance”. Its the next logical step in a planned and organized program. As it should be. But you can’t control what will or will not be picked up by the media.
Maybe I am being bloody-minded, but did we worry about unintended consequences when we drove smallpox into extinction? What about unintended consequences of driving passenger pigeons into extinction? I am not going to worry about driving one or a few species of mosquitos into extinction. Other, more benign species will take their place as food for birds. Not only malaria, but also dengue fever and other diseases will go with them. And tropical diseases are spreading polewards with climate change.
I’m actually fairly critical of gene drive strategies, but not because I think they’re going to have unintended consequences. I just think they’re unlikely to work in the real world (particularly the crash-the-population- gene drive technologies).
And if I recall correctly, not only do not all mosquito species feed on humans, some don’t need to feed on any mammals. I wonder if CRISPR could eventually “fix” the ones that do need blood to reproduce so they’re like their teetotalling sisters…
I addressed this exact question back in 2016. Although subsequent research has suggested that Aedes head peptide doesn’t function the way we thought it did back then. Still, in concept it’s possible.
