# Mosquitos: "the eco-system doesn't need them" **URL:** \ **Category:** In My Humble Opinion\ **Created:** [February 1, 2016, 9:35pm UTC](https://boards.straightdope.com/t/mosquitos-the-eco-system-doesnt-need-them/744882 "2016-02-01T21:35:56Z")\ **Posts on this page:** 1\ **Showing post:** 57
**Author:** ![mozchron](https://avatars.discourse-cdn.com/v4/letter/m/c2a13f/32.png) [@mozchron](https://boards.straightdope.com/u/mozchron)\ **Post date:** [February 4, 2016, 12:35pm UTC](https://boards.straightdope.com/t/mosquitos-the-eco-system-doesnt-need-them/744882/57 "2016-02-04T12:35:24Z")
> [@Sailboat](#): > > Look, I know nothing about genetic modification, so I’m just spitballing here. > > But we don’t hate mosquitoes because they _exist_. We hate them because the _bite us_. And they bite us to get the protein they need to reproduce. > > While we’re bioengineering mosquitoes to die off and stop bothering us, even at the cost of losing their contribution to the ecosystem…how hard would it be to bioengineer them to reproduce without needing a meal of blood? > > Basically make them vegan mosquitoes? > > Then they can continue their role as food animals for many species, but without bothering humans or other animals or making us sick? No more malaria, Zika, dangue, West Nile, etc? What we do isn’t magic you know, its hard! That being said, there might be a kernel of wisdom in this. In Aedes aegypti (and ONLY in Aedes aegypti - this doesn’t apply to other mosquito species) there is a gene called “Aedes head peptide” which is a protein hormone turned on in the mosquito brain after taking a blood meal. When it is expressed, it turns off host-seeking behavior and the mosquito doesn’t feed anymore. Other mosquitoes presumably have similar head peptide genes, but they are so different at the sequence level we have not been able to pull them out of the genomes. Aedes head peptide was isolated old-school in the 1980’s - fractionating mosquito head extracts and injecting them one by one into mosquitoes to see what they did. There are also mosquitoes that can lay a batch of eggs without taking a bloodmeal. This is called “autogeny”. In this case, the mosquitoes store up lots of nutrients as larvae and use them for eggs when they are adults. Problem is it only happens once - after laying the first egg batch they need a bloodmeal for the subsequent ones. Autogeny is a complex trait involving lots of things we don’t fully understand. Aedes aegypti is not widely autogenous (i.e. they generally need blood for eggs), but the trait has been found at low frequencies in some studies. So what we would have to do is engineer Aedes to express head peptide constitutively in their brains to turn off bloodfeeding, while at the same time engineering them to be autogenous. They would lay a single batch of eggs and never feed again. This would have a big fitness cost (as they would have less offspring than wild-type) so we’d have to link the whole thing to a gene drive (probably based on CRISPR/Cas9) to push it into the population. Easy-peasy. Give me about 20-40 million dollars and 10 years and I think we could do it! --- _[View the full topic](https://boards.straightdope.com/t/mosquitos-the-eco-system-doesnt-need-them/744882)._