Some readers questioned whether the strong Iberian affinity apparently found in Egypt in the previous Admixture run focused on North Africans was actually masked Highland West Asian or otherwise non-Peninsular Arab West Asian influences. I was initially skeptic because I had expected by default that Saudi Arabs would represent better all possible West Asian influences than Iberians.
I was mostly wrong as shown here.
Methods: I just run Admixture for K=4, K=6 and K=8 on a selection from the 1000 Genomes sample, following GNXP’s instructions and using the following populations: both Egyptian samples (n=18 and n=12), plus 10 individuals from each of the following populations: Spaniards, Moroccans, Maasai, Ethiopians, Saudi Arabs, Palestinians, Turks and Kurds. The selection of Maasai and Ethiopians to represent Tropical Africans was made because previous research (mine and Henn’s) showed these two being, of the available samples, the ones to best represent ultra-Saharan influence in Egypt specifically.
Results: I am showing only the K=8 results because the lower K levels do not seem overly informative (if anyone wants them, feel free to ask).
1. The K=8 graph:
There is (and I could eventually detect) an Egyptian-specific component, of West Eurasian affinity (look at the Fst table), what implies that it’s surely descendant of the pre-Neolithic Egyptians of Asian origin. Paleolithic Egyptians that I presume existed based on other genetics (mtDNA X1, M1 and such), as well as Eurasian-like iconography like the Qurta rock art, similar to materials from SW Europe and Anatolia (but admittedly the Egyptian Paleolithic, with a few exceptions, is not well known on archaeological grounds being such a sedimentary and then desertic area overall, and also because archaeology in Egypt has been largely focused on the quite impressive pharaonic period).
Besides this component, Egyptians show a diverse array of external influences, possibly Neolithic immigrants (?). The most important ones are the Kurdish or Highland West Asian component (17-20%) and the two Arab components together (14-25%) but others (Berber, Palestinian, East African) are also quite influential. The Iberian influence was largely a mirage (although still weights 4-8%).
Arabian-Egyptian (Arab 2) very distant component:
Also notice the Arab 2 extremely distant Fst values, in the >0.2 range. On first impression I thought they were the Maasai component for that reason but nope. We may be here before another OoA remnant, which is very relevant in Arabia peninsula and also in the second Egyptian sample (c. 12% in both cases) and totally absent in Iberia instead.
Update: K=4 and K=6 graphs, for the record and because some kind of speculation may have some use for them: