Fifteen millennia of human mitogenome evolution in Sicily

Sicily, situated at the heart of the Mediterranean Sea, has been a crossroads of people of different origins since the Paleolithic. To gain further insight into the genetic history of the island from a matrilineal viewpoint, we investigated fifteen millennia of mitogenome evolution. A unique Sicilian mitochondrial dataset, represented by 116 ancient mitogenomes (including 2 newly sequenced) collected from 16 archaeological sites dating from 14,700 to 545 years BP, was compared with a novel collection of 236 modern mitogenomes covering all districts of the island. By integrating demographic modeling with phylogeographic analyses, we were able to identify a statistically supported genetic discontinuity between the Paleolithic/Late Mesolithic and Early Neolithic periods, as well as two mtDNA lineages (U5b and U8b/K) that specifically mark this transition. The high mtDNA variation and lack of genetic differentiation among modern mitogenomes suggest the presence of continuous gene flow from different regions of western Eurasia (since the Paleolithic) and Africa (since the Bronze Age).