Why is sub-Saharan Africa a cold-spot for covid?

[ellenrr]

Could genetic diversity have anything to do with it?

"So let’s rephrase our initial question: Could some ‘populations’ more or less susceptible to Covid-19 because of their evolutionary history?

Given the odious racist history of biological beliefs about human differences, this is a fraught question to ask, let alone attempt to answer. Social scientists, for example, emphasize the socially constructed nature of ‘race’, while rejecting as superficial the possible biological basis to observable differences between racial populations. Population geneticists too acknowledge the myriad social factors that lace through the historical concept of race, and its frequent misuse to support odious racial hierarchies; nevertheless, these geneticists also highlight the growing wealth of data that suggests that individuals in pockets of populations, some small and large, are more likely to have certain genotypically based phenotoypes across certain characteristics. Scientists don’t refer to these as ‘racial differences’ but rather call them population-based differences, and they don’t always correlate with popular and often problematic notions of race."

https://geneticliteracyproject.org/2020/03/31/whats-race-got-to-do-with-it-most-of-sub-saharan-africa-emerges-as-coronavirus-cold-spot-which-may-offer-clues-to-finding-covid-19-vaccine/

[wnylib]

1. There was a DU thread in GD related to this issue

some weeks ago. It pointed out some specific genetic inheritance from Neanderthal ancestors that might contribute to which individuals and population groups are more susceptible to covid infection.

I can't remember now which specific genes were named, but I do recall that there are some Neanderthal genes that make people more susceptible to severe cases of covid, but other Neanderthal genes that actually protect against covid infection. It's a roll of the genetic dice which Neanderthal genes any individual within a population group might have inherited. People who have both types of Neanderthal genes are still more susceptible than people with the protective gene only.

All people whose very ancient ancestry goes back to regions outside of Africa have around 2% of Neanderthal genes. That includes Asians, Europeans, and Native Americans. But, people of Sub Saharan Africa do not have those Neanderthal genes because Neanderthals evolved after their ancestors left Africa and acquired those genetic mutations (both protective and susceptible ones) after leaving Africa. They passed them on to the modern humans (Homo sapiens) whose ancestors left Africa and encountered and mated with Neanderthal in Europe and Asia.

So today's sub Saharan Africans do not have the gene that would make them more susceptible to covid. Neither do they have the gene that would protect them from it. Many people of European, Asian, and Native American descent do have the gene that makes them more susceptible to covid. But some of them have only the protective Neanderthal gene. They might very well be the people who are asymptomatic or seem to be immune to covid.

But, covid is new and Neanderthal was ancient, so how do those ancient genes affects us today? The genes are related to infections from coronaviruses in general.

What about the high incidence of serious infections among African Americans? A large number of African Americans have mixed European and African ancestry. Many of their African ancestors came from the western part of the continent, where contact with Neanderthal was possible in ancient times, not from sub Saharan Africa. Add to that a higher incidence of poverty among African Americans and poorer quality of health care, plus diabetes and they become more vulnerable to covid infection.

This is still being studied so the results of these DNA studies of Neanderthal genetic inheritance are still being analyzed. They are probably not the only factor in infections of covid, but these genes do seem to play a part.