The population genetic structure of Sicily and Greece

[firemonkey]

By total coincidence a paper came out yesterday, Ancient and recent admixture layers in Sicily and Southern Italy trace multiple migration routes along the Mediterranean (I blogged about the topic). It’s open access, and it has a lot of statistics and analyses. I’d recommend you read it yourself.

You see the Sicilian and Greek populations and their skew toward the eastern Mediterranean. But in the supplements they displayed some fineSTRUCTURE clustering, and at K = 3 you see that Europe and the Middle East diverge into three populations. What this is showing seems to be: 1) in red, those groups least impacted by post-Neolithic migration 2) in blue, Middle Eastern groups characterized by the fusion between western & eastern Middle Eastern farmer which occurred after the movement west of the ancestors of the “Early European Farmers” (who gave rise to the red cluster), who were related to the western Middle Eastern farmers 3) the groups most impacted by Pontic steppe migration.

The authors confirm what I reported over two years ago on this blog: mainland and island Greeks are genetically distinct, probably because the former have recent admixture from Slavs and Slav-influenced people. And, many Southern Italians resemble island Greeks.


https://gnxp.nofe.me/2017/05/17/the-...+total+feed%29

[Lucas]

It was also evident from my amateurish analysis thanks to Sikeliot Sicilian and Greek samples. Using K36 values. Who's the boss?

[Lucas]

I can't find this thread maybe Sikeliot remember.

[Sikeliot]

It confirmed the following:

1) Sicily is quite homogenous and close to Calabria and island Greeks (Crete, Dodecanese, etc.), with the exception of Trapani which is a northward outlier*
2) Mainland Greeks form a cluster with Albanians, not southern Italians, and both shift toward their northern neighbors.
3) Cypriots are in fact closer to Sicilians, southern Italians, and island Greeks than to Levantines in professional studies, but somehow not in GEDmatch.

** Note: Syracuse was not sampled. They tend to be northward shifted too, due to more Greek ancestry from the mainland.

[Scholarios]

While Albanian-speaking Arbereshe trace their recent genetic ancestry to the Southern Balkans, the Greek-speaking communities of both Apulia (Griko) and Calabria (Grecani) show no clear signs of a recent (i.e. from the late Middle Ages) continental Greek origin, instead resembling the ‘continuum’ populations of Southern Italy and the Greek-speaking islands (Fig. 3, Supplementary Table S5, Supplementary Fig. S7, Supplementary Information)

Furthermore, we observed that both Calabrian and Apulian Greeks from Southern Italy almost completely lack the ‘Southern Balkan’ genetic component detected in Continental Greece and Albania, as well as in the Arbereshe. In both cases, this is consistent with the fact that their arrival in Southern Italy should at least predate those population processes associated to the more recent (i.e. late medieval) differentiation of continental Greek and Southern Balkan groups (cf. paragraph below). This does not exclude migrations from Aegean/Dodecanese and Crete islands, that presumptively did not (or only marginally) experienced - by virtue of their higher geographic marginality - the North-South Balkan gene flow that instead interested the continental part of Greece.

quite fucking interesting.

[Sikeliot]

What fascinates me is that the southern Italians, but moreover the Calabrian Griko, have such low "European like" genes. The Griko thus must have withstood any foreign mixing for however many millennia as such influences were brought.

What is also, this proves my contention correct that autosomally, Calabria/eastern Sicily do not have any autosomal impact from mainland Greece. I would not be surprised if most of their Greek speaking populations came from the islands, Anatolia, or West Asia.

[Lucas]

What fascinates me is that the southern Italians, but moreover the Calabrian Griko, have such low "European like" genes. The Griko thus must have withstood any foreign mixing for however many millennia as such influences were brought.

What is also, this proves my contention correct that autosomally, Calabria/eastern Sicily do not have any autosomal impact from mainland Greece. I would not be surprised if most of their Greek speaking populations came from the islands, Anatolia, or West Asia.

I think so. Do you agree that difference between Continental Greeks and Island Greeks is similar like between Sicilians and North Italians?