First Peoples: Africans v Everyone else

[madsircool]

In tonights First Peoples on PBS they postulate that Africans never interbred while those escaping Africa bred with Neanderthals. Did this lead to any difference? What were the consequences?

[naita]

Remnants of Neanderthal DNA in modern humans are associated with genes affecting type 2 diabetes, Crohn’s disease, lupus, biliary cirrhosis and smoking behavior. They also concentrate in genes that influence skin and hair characteristics. At the same time, Neanderthal DNA is conspicuously low in regions of the X chromosome and testes-specific genes.

Neanderthals’ genetic legacy: Humans inherited variants affecting disease risk, infertility, skin and hair characteristics

Despite their different approaches, both teams converged on similar results. They both found that genes involved in making keratin—the protein found in our skin, hair, and nails—are especially rich in Neanderthal DNA.

For example, the Neanderthal version of the skin gene POU2F3 is found in around 66 percent of East Asians, while the Neanderthal version of BNC2, which affects skin color, among other traits, is found in 70 percent of Europeans.

The Neanderthal version of these genes may have helped our ancestors thrive in parts of the world that they were not familiar with but that Neanderthals had already adapted to.

Surprise! 20 Percent of Neanderthal Genome Lives On in Modern Humans, Scientists Find

[madsircool]

Thank you Naita…the program didnt try to explain how the neander DNA affected non-Africans. Could these genes be responsible for the alcohol flush syndrom?

[Wendell_Wagner]

The alcohol flush reaction is only more likely among people of East Asian ancestry. Neanderthal ancestry is likely for those of any non-African ancestry. In particular, the alcohol flush reaction isn’t likely for those of European ancestry. So it would seem that there really isn’t any obvious relation between the two things:

Alcohol flush reaction

[John_Mace]

I fell asleep half-way thru, so I don’t remember what they covered. But I know that one hypothesis is that non-Africans acquired genes for immunity to diseases specific to Eurasia. Which would make a lot of sense.

[madsircool]

@Wendell_Wagner

The alcohol flush reaction is only more likely among people of East Asian ancestry. Neanderthal ancestry is likely for those of any non-African ancestry. In particular, the alcohol flush reaction isn’t likely for those of European ancestry. So it would seem that there really isn’t any obvious relation between the two things:

Alcohol flush reaction - Wikipedia

This study argues that Euros and Chinese picked up different Neander genes:

Currat and Excoffier’s conclusions are clearly different. Paradoxically, they suggest that Neanderthal-human sex was less successful and probably rarer, but also more widespread. There’s an easy way to find out which idea is correct. If Currat and Excoffier have it right, then Europeans and Asians should have picked up different Neanderthal genes. That’s exactly what John Hawks found. In his own analysis of the Neanderthal sequences, he saw that Europeans and Chinese people seem to carry different Neanderthal genes.

Strong reproductive isolation between humans and Neanderthals inferred from...

[Wendell_Wagner]

It’s not impossible that the alcohol flush reaction has something to do with Neanderthal genes, but there’s no good evidence for it. All you’ve shown is that there’s some vague possibility that the two things are related. Without some more specific evidence by looking at genetic studies of people with the alcoholic flush reaction and what’s known about Neanderthal genes, there’s nothing more to be said.

Incidentally, where do you get the word “Neander”? I can’t find it (in the sense “concerning Neanderthals” anywhere. I find a few mentions of it in other senses.

[madsircool]

@Wendell_Wagner

Incidentally, where do you get the word “Neander”? I can’t find it (in the sense “concerning Neanderthals” anywhere. I find a few mentions of it in other senses.

Just laziness on my part because I didnt want to type (and then correct my spelling) of the whole word. :o

[twhitt]

@Wendell_Wagner

Incidentally, where do you get the word “Neander”? I can’t find it (in the sense “concerning Neanderthals” anywhere. I find a few mentions of it in other senses.

Neandertal and Neander Valley are different ways (in English) to name the valley in Germany where Neanderthal was discovered and for which it was named. In that sense it’s accurate, if not the most common. I don’t know about using it the exact way madsircool and can’t comment on that.

Oddly, I’m not sure which name came first: the word means New Man, so it makes some sense if the valley was named for the species, though that doesn’t appear to be right and I don’t have evidence.

[Wendell_Wagner]

Yes, I know that the word “Neanderthal” comes from the German word for the Neander Valley. As to which way the derivation went, all you have to do is look at the Wikipedia entries. The Neanderthals were named after the valley. The valley was named after a man called Joachim Neander. “Neander” was a translation into Greek (well, sort of) of the common German name “Neumann” which means “new man” in English. His grandfather had changed the family name from Neumann to Neander. Apparently it was the hip thing to do back then:

Neanderthal

Neanderthal

Joachim Neander