no, i don’t know much about them, but via the italianthro blog, here’s a couple of charts from tian, et. al.’s European Population Genetic Substructure: Further Definition of Ancestry Informative Markers for Distinguishing among Diverse European Ethnic Groups (*whew*). northern italians are the little white triangles outlined in black — italians from the u.s., mostly southern italians, are the little yellow triangles outlined in black — and people from tuscany are the green diamonds with the dark green outline:

notice that there’s not much overlap between the northern italians, tuscans and southern italians. in other words, they’re different populations. they’re not wildly different populations — it’s not as if there were eskimos living in northern italy and australian aborigines living in southern italy — but they are different.

dienekes has found that there is a greater north african component (K=6) in southern italy/sicily than in northern italy:

and also that there is a greater northwest european component (K=10) in northern italy than in southern italy/sicily:

italianthro has objected to me having said about italy that there are: “different populations — broadly speaking, more germanic in the north, more greeks and arabs and others in the south.”

in one way he is correct — the genetic differences between northern and southern (and maybe central) italians is not due to just an influx of germanic, greek and arab genes into italy/sicily. i will readily admit to having been incorrect to put it like that. but there are genetic differences in italy’s population — the people living in italy/sicily are not entirely one people. the differences, tho, probably go back further than the arrival of the greeks and goths, so it was not right of me to just point to the german, greek and arab migrants, although they also contributed to the genetic differences that are found in italy today (for example).

that the genes of italians living in different regions of italy look somewhat distinct is the nature of genetics. if you compare my genome to my first-cousin’s, they’ll look rather different. but if you compare my genome and my first-cousin’s to an eskimo’s genome, then me and my first-cousin are going to look awfully alike.

tian, et. al., mentioned this about their italian samples:

“It also is worth noting that the inclusion of the Arab population groups results in larger separation between northern Italian and southern Italian (and/or Greek) subjects and suggests that inclusion of the Arab population genotypes may be useful in analyses of southern European population groups (data not shown).”

in other words, the southern italian samples were pulled farther away from the northern italian ones, towards the arab samples. that’s because there’s some amount north african/arab genes in the southern italy population — or, rather, that southern italians share genes in common with north africans/arabs.

when geneticists drill down further into italian genetics, they’ll no doubt find even greater differentiation; but at the same time, clearly italians are, on average, different from arabs or africans or eskimos.

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