Would it be feasible to suggest using CRISP to create another adaptation to the gene, one that preserves the mosquitoes but makes them unable to transfer the disease to humans?
Eliminating a species because we don't like it reminds me of speciesism as Peter Singer outlines in one of his books. (Animal Liberation I believe it was). Where humans assume another species to be inferior and have less of a right to live a decent life.
I do think it's a normal response to value human life more. And in fact, I also do think that in this case it makes more sense to safe the humans if no other approach is viable..
As for the rest, yeah tricky business. By all accounts we have more value than a mosquito, but as you move up the food chain what are the unintended consequences?
Eliminating entire species deliberately, on the other hand, isn't really better. Yes, there is the us vs. them dilemma, and of course we should favour our own species if there's no other option, but this should be used as a last resort only.
I wonder if there's anyone looking into using similar methods to make humans malaria resistant instead.
Both can potentially have unintended and disastrous consequences hundreds of years into the future.
My understanding is that out of 3,500 mosquito species, only about 40 transmit malaria. Most of what I've read from experts implies they're not sure that mosquitoes play any biologically important role at all, and it seems like if there is some role (other than killing humans), the other 99% of non-eradicated mosquito species could fill in that gap.
In my (decidedly non-expert) opinion, that's good enough to start making moves towards eradicating the mosquito-causing species.
How about eliminating them because they are killing us, literally by the millions? Viewed that way, it seems more like normal self-defense to me. Currently mosquito-borne diseases kill around 700,000 people each year; this figure does not include the cost to society of the people who become ill but later recover. Source: https://en.wikipedia.org/wiki/Mosquito
How about if you consider things like bacteria? The rabbit-hole of "speciesism" never ends...
So I would focus in those problems instead of trying to inject suicide genes into the wild.
I like the saying: the opposite of well done, is well intented.
No one can fix this with a snap of their fingers. You have to reform (replace?) governments, change cultural standards around sanitation, build tons of infrastructure. No matter how much aid is sent, it will take a long time even in the best case. These problems won't be fixed for good in the near future.
Perhaps malaria can be made a thing of the past before then. If so, don't let hundreds of thousands die because we "should" be fixing poverty instead.
Perhaps along with the last remaining shreds of intact eco systems that remained. Oh and perhaps some suicide genes end up somewhere else.
Millions of lives currently depend on reducing mosquito populations, so methods of control will be used no matter what. Targeting a specific species of mosquito rather than spraying DDT everywhere will reduce the collateral damage to the environment immensely.
Altering genomes of living organisms with the intention of wiping out a species ... has a potential unlimited side effect.
I especially like the second example: fighting the toad in australia. Originally the toad was brought in to mess with the local ecosystem ... then it messed too much and now the solution is altering the genome with a exponentional bigger impact.
Isn't that real live satire? I mean how could that possible go wrong, since we understand everything about ecosystems and the genome today and are masters about controlling complex systems ...
> Malaria is only carried by a tiny number of mosquito species. Of the thousands of species only something like a dozen actually matter to humans. We can target exactly the ones we want and even better : nothing stops us from maintaining a population in some labs somewhere.
If it turns out they matter in any significant way, contrary to various impact analysis... we just release them back into the environment.
> The current cost of not wiping out those few mosquito species is about half a million dead children.
Imagine that someone was nuking a mid sized American city every year and you could stop it right now but you'd prefer to wait for a slightly more athsteticly pleasing solution.
> How much blood would you be willing to let stain your soul .
Keep in mind that, in this case, extinction is a side effect of another antimalarial effort.
Also Seems like you skipped over this part:
> nothing stops us from maintaining a population in some labs somewhere. If it turns out they matter in any significant way, contrary to various impact analysis... we just release them back into the environment.
...Re-releasing them, after the environment has adjusted to their absence, does not return you to the original state.
The cascade of known, expected and unexpected comsequences from wiping mosquitoes could be enough to distroy the economy of entire countries.
And is so easy to think in believable sceneries that is astonishing to see people repeating again the mantra that nothing is proved and nothing will happen.
Wiping mosquitoes in Africa could affect profoundly Europe, for example.
The same birds that save harvests in Europe each year, pass the winter in Africa. Finding some alternative food, here and there, is not the same as "finding enough fuel to not die in the return". Do we really want to start an experiment that could lead to Europe losing decens of insectivorous birds overnight and episodes of famine in many points of Europe?
Or... What if malaria strikes back being forced to jump to the next species of mosquito available, those able to stand cold temperatures that can be found in Scottland or Swedden?
No more roses with thorns (they cause thumb injuries), sweet smelling stink bugs, glow in the dark pets.
Can't imagine what could go wrong. Someone needs to be writing the movie plot right now.
AFAIK human "races" are largely superficial biologically - there are some correlations, but weaker than the variability between individuals.
Like when you get your driver license or open a bank account. Coming from Europe I was surprised by such a question. Racial issues run very deep in the US.
Now CRISPR alters the specific sequence that it targets. In fact, CRISPR only cuts the DNA at that sequence, other proteins must be employed to change and then fix the DNA. It may be well enough to simply cut up a specific race's DNA and leave it at that. Or if those cells die off too fast, splice in some garbage DNA that will at least let the cell reproduce.
Wading into a minefield here, but is this even remotely true?
My understanding of DNA testing is that it can only tell you what genes a person has. I wasn't aware of any reliable way to cluster genes into racial groups. (The 23 & me stuff is all probabilities, wide percentage ranges, etc.)
Further, I thought it was the case that science has basically abandoned the concept of race specifically because it couldn't be reliably measured, even by DNA analysis. Is this not the case?
What am I missing?
Popular understanding of race (it's a social construct, so this is the relevant metric) has little or nothing to do with susceptibility to a given disease. Similarly, dark skin != what we commonly think of as "black" (think dark-skinned people from Asia, for example).
For example if you have a dark skinned person with epicanthic fold, chances are that's a person from Indonesia or its whereabouts.
Race is not ONE trait, it's a set of traits, and all of them are encoded in DNA.
Or South Africa, or east Africa, etc. Or since we're talking about people and not geographic features, we could be talking about a person in the e.g. Americas who is the product of many "origin" regions of the world.
> Race is not ONE trait, it's a set of traits, and all of them are encoded in DNA.
The problem is the "set of traits" is squishy and often defined in the moment. This, plus the importance we assign to race in all affairs, has led many societies to try to codify what is meant by race. Racial distinctions are different in the context of different communities (e.g. in the US it's very important to know who is "black" vs who is not).
For example, in the US we long practiced the One-drop rule , which lead to absurd racial classifications  that required you to know a person's entire ancestry back 3 or 4 generations in order to identify her race (obviously, this is recursive).
The trouble is we start from a position of knowing how we want to classify a person, by seeing them or knowing where they come from ("I know she's black, so my classification scheme needs to ensure she's black."). We then need to apply tools (one-drop rule, etc.) to make sure that person fits the classification.
Gene clusters are a clumsy way to accomplish the same thing using modern tools. Obviously some populations share some traits. But saying "race" is something that can be objectively identified for every given individual is naive.
Back to your original point -- there's no such thing as the "last few genes" that make a person black. That's approximately like saying the last few quanta of pigment in a person's skin change their race. Or that a person's race can be determined by calipers . It's ridiculous.
1 - https://en.wikipedia.org/wiki/One-drop_rule
2 - https://en.wikipedia.org/wiki/Quadroon
3 - https://en.wikipedia.org/wiki/Phrenology
QED there's no biological basis for race.
Yes, races are largely a social concept. However, once society has defined races based on whatever phenotypes that are in fashion at the time, it turns out that yes, there is a biological and genetic basis for those phenotypes. It's conceivable that this biological basis could be targeted by some gene-based technology. Probably not very accurately, but based on past observations I'd say that racist mass murderers are not particularly likely to care about such subtleties. And that's what matters for the GP's point.
- where we see a person
- who this person is with
- what clothes the person wears
- what a person smells like
- body language
- spoken language
- the manner in which they speak (loud, soft, etc.)
- the way they walk
- all sorts of other cultural markers (like stance, eye contact, etc.)
I suspect that all these contextual, largely non-biological factors play a huge role in how we decide a person's race. Possibly so much so that the biological markers we do have available are mostly useless.
Please correct me if I'm wrong though; I am far from an expert in this area!
I assume your worry is that it might selectively activate in some race to do a bad thing? But that's not how it works. It always activates, and the only thing keeping it within the mosquito species is that they physically can't breed with anything else. And obviously no such barrier exists with races.
So we could worry about a completely different and theoretical technology, but not so much this one.
Humans reproduce far slower than mosquitoes, and if someone managed to modify a few humans, there would likely be plenty of time to detect it and fix or contain it in some way.
Well, that was that.
The proposed gene drive causes male mosquitoes to produce sperm that, when it fertilizes egg cells, will lead to only make offspring. After several generations of this spreading, eventually all offspring will be male, and that will be the last generation.
The gene drive does this by attacking the genes in the mosquito sex determination system called doublesex. I guess, no-one has discovered a similar vulnerable mechanism in the malaria plasmodium sex determination genes. The malaria plasmodium is a single-celled organism, and it goes through both asexual and sexual reproductive phases in its life cycle. But it does go through the sexual phase, too.
Before anybody says "well actually there was a study that said nothing bad would happen", the horribly flawed studies about wiping out mosquitoes being harmless acts under the assumption that animals that feed off mosquitoes will find other insects to live off of. With insect populations dropping to tiny fractions of what they were years ago, it's incredibly short-sighted to think that's feasible. It's the same as saying "all the rice in the world could vanish and humans would just eat something else." Technically, yes, but taking away a large portion of so many people's daily calories isn't a good idea. And looking at how fish, amphibian, bat, and bird populations are lower than ever, getting rid of a readily available food source that links entire ecosystems together is pretty selfish. Work on treating the diseases instead of taking the easy way and just destroying things.
- there are several parasites that fall into that umbrella
- none of them give you permanent immunity or even permanent resistance to reinfection, so we can't crib from those metaphorical notes to find a good vaccine
- the parasites are developing drug resistance/immunity
So while I agree we should be extremely careful about even considering wiping out a species on purpose, it's not for lack of exploring other options that we're at this point.
But we know nothing comes for free, no good human deed goes unpunished.
There's a lot of debate about whether destroying malaria-carrying mosquitoes would have any side effects whatsoever. Alternately, it may have some.
I don't think your characterization is fair, in other words. Those of us in areas not immediately affected are insulated against that emotional response, but we must be aware of the reality of malaria's toll. But destroying an entire species is a draconian approach that should require a great deal of thought.
We know nothing of the sort. Perhaps this is something you know.
That said, I think it's possible, but I'm very skeptical that eliminating a species will be free of indirect effects.
One has the sole effect of making humans healthier. The other is linked to far too many things to predict the outcome of. Considering dragonfly nymphs have mosquito larvae as a stable food source, it's safe to say that knocking them out will probably affect them. Then follow that food chain up (and down) and things start to get complicated.
That aside, millions of human deaths (annually or in total) is a horrific tragedy, but if we, say, managed to render a large area of land uninhabitable through ecological collapse for a generation or more, it might be far worse, both in some imaginary absolute scale, and for the people directly displaced.
Now, if you can eliminate the malaria within the mosquito, that's something else entirely.
Perhaps this is observational bias from your part? Human brain detects negatives far easier than positives.
The world is a complex place, and any action that has externalities likely creates both negative and positive ones - and for some people even same effects can be negative for some and positive for others.
Yes, bad things can happen for anyone. Generally, though, I would say deeds of compassion breed compassion.
There's nothing to be lost in doing a trial in an isolated area. The world is vast, we don't need to eradicate mosquitoes at the same time everywhere...
The ongoing insect apocalypse is a problem, a potentially civilization-ending one. But wiping out malaria wouldn't be, and at this rate we'll probably do it by accident even if we don't implement this.
And perhaps it is worth to consider using a domain of technology - biotechnology - we have yet to understand better? Every tool comes with it's price, and so does CRISPR/Cas9. Gene drives can override and change the hereditary mechanism which makes genes propagate in populations. There are possible second order effects in place, which would be very important to rule out before applying such a method in the wild.
<irony>Unless... unless, of course, we are happy with the import of rabbits et al to Australia.</irony>
(The eradication of this particular mosquito species is likely harmless, but that does not matter. We should do it even if it isn't)
A) the use of a technology - a gene drive - we have no full control of in the wild
B) the act of eradication of a species
to help to lower the loss of human life in Malaria affected regions.
Your statement regarding the Australian ecosystem engineering is purely hypothetic. The import of alien lifeforms always had a detrimental effect on ecosystems, and often, as a second order effect, on humans as well.
It scares me how a lot of people think that it is not worth thinking and evaluating the use of a technology. Perhaps it is because they have no experience and knowledge in this particular domain of science?
That depends on the level of risk to other species, in case these genes leak across some barrier.
Which might be fine, but you need to, uh, check.
Was it worth it? Yes, but all the consequences have not yet come home to roost.
Odd that you lead with the dismissal of one logical fallacy and then in the short space of this comment fall into the trap of using another one yourself.
We ought to think twice before expediting this
"many fish leeches directly transmit several blood parasites"
"Consequently, the leech is a potential vector of many pathogens, especially in regions with an endemic spread of human and/or animal pathogens."