Comment by lmpdev | Hacker News Reader

Comment by lmpdev | Hacker News Reader

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Also don’t forget the vast majority of genetic diversity in homo sapiens is found in subsaharan Africa

Much potentially vital genetic information can be found in the Congo, but also more “attack vectors” for novel pathogens

The DRC specifically is packed full of heterogeneous ethnic populations with varying levels of ethnic mixing, on the scale of 100-250+ distinct genetic groups

These groups often have higher genetic diversity between them than all “white” peoples globally

Diversity on the whole is a good thing, but can be dangerous in potentially hazardous environments (such as the close, effectively forced daily animal contact you’d find in the DRC)

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This also applies to other mammals, eg why you see so so many Bat-bourne illnesses, as they have by far the most genetic diversity of any mammal group

We have these harmless fruit bats here in Australia, but friends and family are sometimes startled when I tell them off for approaching injured or dead bats. Alive or dead they’re extremely hazardous to humans - even placid ones

> Much potentially vital genetic information can be found in the Congo, but also more “attack vectors” for novel pathogens

I don't think it quite works that way. At least, I only ever hear about a lack of genetic diversity being a threat in the context of diseases and immunity (usually in the context of domesticated animals and cloned plants, like bananas). And there the argument is that once a virus has way in, it can spread to everyone else genetically similar enough.

So I think this is mixing up two views: one takes all genetic variation out there, and asks "if I were to unleash this novel virus on all of them, would any of them be infected?" The higher the diversity, the higher the chance that at least one happens to have the genetic make-up that is accessible by a virus.

But the actual questions are closer to "how many would be infected? How easy would the virus spread?" In that case I would expect higher genetic diversity to result in lower numbers. Like a kind of soft herd-immunity in diversity.

I'm not an expert though, so if anyone who does know their stuff in this matter could weight in that would be appreciated.

Also, as far as I understand the problem for bats is that they share (predigested) food with their fellow bats in their colonies. So if one is sick with anything, all of them will be exposed.

I know almost nothing about genetics or virology, but perhaps GP is saying the close proximity of genetic similarity allows viruses to mutate and infect people it otherwise wouldn’t. For example, say Person A had a virus, and under no circumstances would Person A ever infect Person C due to Person C being just barely genetically different enough from A. Then we put Person B into the mix who is “halfway between A and C” (quotes because that’s probably not precisely how genetics works, but I don’t know). The virus infects B, then mutates and infects C.

Wouldn't this average out? You'd have more attack vectors but you'd also have more "reactor control rods" throughout in the population.

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