Complete mitochondrial sequences from Mesolithic Sardinia

Abstract

Little is known about the genetic prehistory of Sardinia because of the scarcity of pre-Neolithic human remains. From a genetic perspective, modern Sardinians are known as genetic outliers in Europe, showing unusually high levels of internal diversity and a close relationship to early European Neolithic farmers. However, how far this peculiar genetic structure extends and how it originated was to date impossible to test. Here we present the first and oldest complete mitochondrial sequences from Sardinia, dated back to 10,000 yBP. These two individuals, while confirming a Mesolithic occupation of the island, belong to rare mtDNA lineages, which have never been found before in Mesolithic samples and that are currently present at low frequencies not only in Sardinia, but in the whole Europe. Preliminary Approximate Bayesian Computations, restricted by biased reference samples for Mesolithic Sardinia (the two typed samples) and Neolithic Europe (limited to central and north European sequences), suggest that the first inhabitants of the island have had a small or negligible contribution to the present-day Sardinian population, which mainly derives its genetic diversity from continental migration into the island by Neolithic times.

Population history from the Neolithic to present on the Mediterranean island of Sardinia: An ancient DNA perspective

“…This new evidence points towards Neolithic Sardinian individuals descending principally from mainland Neolithic populations. This hypothesis is also consistent with a signal of population turnover associated with the Neolithic transition observed in Sardinian ancient mtDNA (M odi et al , 2017), and with a gap in the Sardinian archaeological record before its Neolithic transition (L ugliè , 2018).…”

“…G hirotto et al (2009) contrasted patterns of continuity between Ogliastra (the mountainous and historically isolated central region) and Gallura (a region in northern Sardinia with cultural and linguistic connections to Corsica), finding evidence for more genetic turnover in Gallura. M odi et al (2017) provided the first complete mitogenomes of two Mesolithic individuals and found support for a model in which Mesolithic ancestry on the island was replaced by incoming populations in the Neolithic. O livieri et al (2017), in a companion project to the work described here, analyzed 21 ancient mitogenomes from Sardina as well as 3,491 mitogenomes from contemporary Sardinians and estimated the coalescent times of Sardinian-specific mtDNA haplogroups finding support for most of them originating in the Neolithic or later, but with a few coalescing earlier.…”

Late Upper Palaeolithic hunter-gatherers in the Central Mediterranean: new archaeological and genetic data from the Late Epigravettian burial Oriente C (Favignana, Sicily)

“…In the last few years, developments in sequencing techniques have enabled the generation of an unprecedented amount of genomic data from past populations. In particular, ancient genomes from Upper Palaeolithic and Mesolithic periods have made it possible to explore the early genetic makeup of hunter-gatherers of the (Jones et al, 2015; Fu et al, 2016; Hofmanová et al, 2016; Posth et al, 2016; Modi et al, 2017; Mathieson et al, 2018). Given its geographic location and the presence of Upper Palaeolithic and Mesolithic human remains belonging to at least 3 individuals (Oriente A, B and C: Mannino et al, 1972; Lo Vetro and Martini, 2006; Di Salvo et al, 2012; Mannino et al, 2012; Martini et al, 2012a), Grotta d’Oriente, on the island of Favignana (SW Sicily), is a key site for the study of the human colonization of Sicily during the Upper Palaeolithic (Lo Vetro and Martini, 2012).…”

A genetic perspective on Longobard-Era migrations

“…Sequences were demultiplexed and sorted according to the sample, then raw sequence data were analyzed using the pipeline described in 12 . Merged reads were mapped on the revised Cambridge Reference Sequence, rCRS (GenBank Accession Number NC_012920).…”