Is ApoE4 Neanderthal?

[mike]

E4 seems to be most prevalent in the higher latitudes, and in the lowest (equator). I've seen some research where they were trying to use historical temperature to equate that it is higher metabolic rates. Seems a bit tortured... Other research shows E4s do not metabolize glucose as well as E3s (E2s are better than E3s), but E4 and E2 both use ketones better than E3s. E4s would have survival advantage over E3s in areas where man had to go through feast/famine cycles where internal fat (ketones) would be used - this would account for the Northern European concentrations of E4, but not the equator. I postulate that in the equator region, there is access to external ketones in the form of coconut that would also give E4s a survival advantage. Yes/No? Thoughts?

[mike]

I added this graphic in another post, but think it is better here. I'm very jealous; I've been looking for the data to create just such a map, and someone beat me to it! This is the best map I've seen of the World distribution of ApoE4. It is much different than I had imagined from other descriptions. Sub-Saharan Africa has the most. Middle East has the least. Europe goes from medium in the south to higher in the north. Malaysia and Indonesia were also high. This actually makes sense when you look at early man. Originally, there was ApoE4 and early man was just in sub-Sahara Africa. The Sahara blocked travel out of Africa, but there is a 20,000 year climate wiggle, and the band of livable and unlivable areas change. Early man comes out of Africa early with just the ApoE4 allele and travel along the coast to Indonesia and also to Europe and Asia. Later, during a period when the Middle East was more green, another group came out of Africa and settled here. ApoE3 comes on the scene and provides advantage in areas with more abundance and availability of constant carbs (tubers, later farming). ApoE4 holds out in Northern Europe because of the cold and less carbs. Sub-Sahara Africa keeps its ApoE4 since most genetic mixing is out of Africa, not in. Malaysia and Indonesia keep it since it is also more isolated. The new world for the most part matches the people in Europe where they came from. I then added the 2nd attachment, that shows modern man's exodus out of Africa with some rough dates. The percent of E3 could also be a factor of when recent modern man got to some areas - with modern man not getting to Malaysia and Indonesia until about 50,000, and with norther Europe covered in ice until relatively recently. Instead of trying to do a tortuous data analysis with latitude, makes more sense just to look at maps...

ApoE4World.PNG

ApoE4Travel.PNG

[mike]

One possible explanation is that the interbreeding happened later in the middle East, where the Neanderthals had darker skin

yes I think you are correct here. Look at my last post.

[mike]

So ApoE4 is Neanderthal... If you come from Northern Europe anyway. Not so much if you are Indonesian. Then it comes from Denisovans. In between, it looks like it would have come from a combination of the two, since there was periodic mixing. And then let's not forget about Modern Man spreading out from the Middle East; they would likely have had more ApoE4 earlier on when they were first spreading out.