Ailichu/ratchet fan: Since this thread is specifically about Sicilian DNA, I am going to maybe be a little more blunt, but hopefully in a respectful and civil manner and hope it is taken as such.
I think the statement that European and Near Eastern are not valid genetic groups is not entirely accurate. I think it is well known here on this site that West Eurasians were one group some 50,000 years ago, admixed with Neanderthals and then spread into various "distinct populations" but related in that they all stem from West Eurasians.
This first paper by Jones et al 2015 is one that I am aware of that measures the time of divergence among some of the populations that are discussed in the Lazaradis et al 2016 paper, which is also linked.
https://www.nature.com/articles/ncomms9912
Lazaridis et al 2016 Figure 1 lays it out. The term "Middle Eastern" is to me a specific term for modern Arab-Islamic culture, Arab being a language pretty much that developed in the early part of the first millennium AD. The term "Near Eastern" is a broad term that captures, as Figure 1 indicates below, Anatolian Farmers, Caucus Hunter Gather (CHG), Iran-Neolithic (IN), Levant Neolithic, Natufians and would also capture, although not ploted in Figure 1, peoples from the Arabian peninsula (Bedouins) who were nomadic peoples living across the deserts of modern Saudi Arabia and into deserts in Assyria during ancient times. Best I can tell, I have never seen any ancient DNA from this area. I think it is clear that those ancient populations were distinct enough to cluster separately, but of course related enough to cluster relatively in the same area code. I don't think anyone here who is of Italian, Greek or of ancestry from other countries on the Balkan peninsula denies they have significant ancestry from Anatolian-Europeans (EEF).
https://www.nature.com/articles/nature19310
The well cited Raveane et al 2019 paper states clearly all modern Italian Regions have significant Anatolian Neolithic ancestry, ranging from 56% (SItaly1 sample) to 72% (NItaly4 sample). Other ancestries identified in that paper include Western Hunter Gather (WHG), Caucus Hunter Gather (CHG), Iran-Neolithic (IN), Eastern Hunter Gather (EHG) and some North African (likely from Phoenician period and again Saracen period) in Sicily. I think what some people take issue with, I am in this group, is that when "middle eastern" is used that means I am being told that I am ethnically "Arab-Bedoiun" or ethnically Levantine. I am not, not that those are all great civilizations, some of the greatest civilizations were in the Levant (ancient Pheonicians) and the nearby civilizations near the Euphrates (Summeria, etc) which is where the Levant's border ends. And for the record, just because the Normans ruled Sicily in middle ages and Vandals in 4th/5th century AD doesn't make me a Viking or German. I am neither of those as well.
In my experience there are 2 types of people who use "middle eastern" in ways that suggest agendas, 1) one is based on making themselves the I guess standard of Modern Europeans, those tend to be more of those with Nordicist views and argue Northern Europeans are the standard for who Europeans are. The other are again, in my experience, 2) use it to argue against strict border enforcement for illegal migrants from modern Middle East countries. The first one is nonsense. Europe is Europe, Northern Europeans can be Northern Europeans, Eastern Europeans can be Eastern Europeans, NW Europeans in the British Isles can be NW Europeans, Central Europeans can be Central Europeans and by damn Southern Europeans can be Southern Europeans. The 2nd point is more of a political issue that is one that I agree with, border controls are needed, immigration needs to be legal and be a 2 way street for both host country and immigrant. But that is a political issue that is more for the political board (Ailichu and I have had private conversations on this political issue).
Since this thread was about Sicilian DNA, that is what I am interested in. What explains how I got to be what I am and how Sicily got to be what it is and how it relates to other populations in Italy from other regions historically such as how close did the DNA source populations from Mesolithic to bronze age in Sicily mirror the same period in Southern Italy, in Rome/Lazio, Central to Northern Italian Alps (i.e. Otzi the Iceman, who I just found out via MTA Chroma analysis I share DNA segments with). So I personally want source populations correctly identified as to what they are and what they are not. Lumping all those populations documented in Lazaradis et al Figure 1 is just not correct.
That is my honest take on it, Cheers.