The Ultra-Selfish Gene | Hacker News Reader

The Ultra-Selfish Gene

worksinprogress.co

96 pointsjml7c520 comments

We're already engineering ecosystems in a thoughtless way. I find it hard to believe that messing with mosquito genetics is going to make the world significantly more risky than it already is for humanity.

Ecosystems are complex systems that can't be perfectly modeled. So its possible that just the right perturbation could cause outsized harm and that we wouldn't be able to tell ahead of time what that might be.

Just because we've 'gotten away' with messing with ecosystems so far does not mean that we continue to do so indefinitely.

It's like saying its hard to believe that a single additional straw could break a camel's back when so many have been piled on before without issue. You're right until, suddenly, you're wrong.

> It's like saying its hard to believe that a single additional straw could break a camel's back when so many have been piled on before without issue. You're right until, suddenly, you're wrong.

And in this case, the example is updated that even any single straw could break / could have broken the camel's back.

Reading that "The astounding power of gene drives" makes the concept clear but I wonder - how could this not happen by random chance periodically? Maybe it's too infrequent to catch but doesn't it seem like occasional some species should just go extinct for seemingly no reason?

Further why wouldn't this be a positive attribute if one species could inflict it on another? I guess that's far fetched but I'm willing to admit that the logic of species interactions could very well be something that I haven't thought out.

Biology is very complex and contrary to public believe generally wasteful and not efficient and also not beautifully designed and in harmony but messy, and so is genetics. The chance that a single random base pair mutation (not a gene) actually gets activated/expressed and forms a functioning protein that is even advantageous for survival and gets passed down to descendants is tiny. Cancer or a rare genetic condition is much more likely.

One thing I am not understanding here is why not target the malaria parasite itself, instead of the mosquito? (Other than the obvious fact that mosquitoes are annoying) it seems like that would be the route of abundant caution with minimal consequences?

AFAIU, current mature gene drive solutions depend on sexual reproduction. Protozoa usually reproduce asexually, and Plasmodium falciparum in particular is haploid--only one set of chromosomes--during the part of its lifecycle in humans where it principally reproduces.[1] I'm not a scientist but I think this poses unique and probably more difficult engineering problems for building and using a gene drive, and we're not nearly as far along the curve in understanding and resolving them.

[1] The process is pretty complex: https://en.wikipedia.org/wiki/Plasmodium_falciparum#Meiosis Seems like maybe there's opportunity there when it infects the mosquito, though: "Such gametes can fuse within the mosquito to form a diploid (2N) plasmodium zygote, the only diploid stage in the life cycle of these parasites."

What if we used gene-drive to modify the mosquitos so that malaria cannot use them as a host?

That's not a bad idea- but you'd have to actually figure out how to do it, we already know how to do a gene drive.

The article discusses this as the tact taken by the Malaria Initiative.

https://stopmalaria.org/

That's the best explanation of CRISPR and gene drives I've seen.

It's my understanding that the gene-edited mosquito trials have largely failed, since after a few generations the female mosquitos evolved to avoid the gene-edited males.

Wow bummer, do you have a good link about that?

Screw worms are controlled very successfully this way, although they are sterilized via radiation not genetic modification. I wonder if that makes a difference.

Sorry to ask you for a link and use a YouTube video as my source but it's the best I got right now: https://youtu.be/Olj8arvfYj4

Releasing sterilized male mosquitos into the environment also works very well, but is of course not gene drive, and you have to keep doing it to keep populations low.

Oh ok I thought that's what OP was referring to.

We should have a govt agency tasked with destroying the couple types of mosquitoes that bother humans.

The US Gov does this in Panama, but for flies that bother livestock.

https://youtu.be/Olj8arvfYj4

Am I understanding correctly that the main impediment to weaponizing this gene drive idea is the difficulty of spreading the treatment to a broad population? How are these things applied to a live subject, anyway? I had always assumed an injection, but maybe an aerosol could be produced? Hopefully not.

It is applied to the fertilized ovum or early stage embryos I think. At least that seems to be what He Jiankui did: https://www.npr.org/2023/06/08/1178695152/china-scientist-he...

Too bad this article didn’t get more traction. Very interesting!!

Reply on news.ycombinator.com