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Cruciani, F.

Publications and source records attributed to Cruciani, F..

7 recordsLinked to original sources

LAYERED GENOMIC COMPOSITION AND LINGUISTIC CONTINUITY IN GRECIA SALENTINA

Grecia Salentina (GS) is the label assigned to a geographic area in Southern Italy where a Greek dialect has historically been spoken. The origins of this Greek-speaking community, whether dating from ancient or Medieval settlement, are a controversial and essentially unsolved issue. To evaluate which historical-linguistic scenario is best supported on genomic grounds, we used whole genome sequencing of 27 GS natives and 21 controls, embedding them in a 799 modern samples dataset in which Greece and Anatolia were evenly represented, an uncommon feature in the genomic literature on the area. We considered different aspects of the genetic structuring, at different spatial and temporal scales. Analyses also included 4021 ancient samples from the literature. All analyses pointed to the same conclusion: the GS genomic profile displays the same characteristic features of the rest of Southern Italy, with no definite evidence for a single source population from outside Italy. Correspondingly, we detected strong genetic connectivity among GS municipalities and between GS and the rest of Italy. Only a subset of our analyses suggested a slightly increased affinity of GS with Greece, or with the Anatolian peninsula. These results indicate that GS has been all but a genetically closed community, and that the Greek language did not act as a barrier to gene flow. By endorsing a ''transient mobility model'' we support the most recent linguistic hypothesis: the prolonged resilience of the Greek language in GS, maintained in situ and periodically rejuvenated through recurrent external inputs from the Greek and Byzantine worlds.

genetics↗

The arrival of the Near Eastern ancestry in Central Italy predates the onset of the Roman Empire

Italian genetic history was profoundly shaped by Romans. While the Iron Age was comparable to contemporary European regions, the gene pool of Central Italy underwent significant influence from Near Eastern ancestry during the Imperial age. To explain this shift, it has been proposed that during this period people from Eastern Mediterranean regions of the Empire migrated towards its political center. In this study, by analyzing a new individual (1.25x) and published Republican samples, we propose a novel perspective for the presence of Near Eastern ancestry in the Imperial gene pool. In our scenario, the spread of this genetic ancestry took place during the late Republican period, predating the onset of the Empire by [~]200 years. The diffusion of this ancestry may have occurred due to early East-to-West movements, since Eastern Mediterranean regions were already under Roman political influence during the Republic, or even as a result of migration from Southern Italy where Greeks and Phoenicians settled.

genomics↗

The Genomic portrait of the Picene culture: new insights into the Italic Iron Age and the legacy of the Roman expansion in Central Italy.

BackgroundThe Italic Iron Age was characterized by the presence of various ethnic groups partially examined from a genomic perspective. To explore the evolution of Iron Age Italic populations and the genetic impact of Romanization, we focused on the Picenes, one of the most fascinating pre-Roman civilizations, who flourished on the Middle Adriatic side of Central Italy between the 9th and the 3rd century BCE, until the Roman colonization. ResultsWe analyzed more than 50 samples, spanning more than 1,000 years of history from the Iron Age to Late Antiquity. Despite cultural diversity, our analysis reveals no major differences between the Picenes and other coeval populations, suggesting a shared genetic history of the Central Italian Iron Age ethnic groups. Nevertheless, a slight genetic differentiation between populations along the Adriatic and Tyrrhenian coasts can be observed, possibly due to genetic contacts between populations residing on the Italian and Balkan shores of the Adriatic Sea. Additionally, we found several individuals with ancestries deviating from their general population. Lastly, In the Late Antiquity period, the genetic landscape of the Middle Adriatic region drastically changed, indicating a relevant influx from the Near East. ConclusionsOur findings, consistently with archeological hypotheses, suggest genetic interactions across the Adriatic Sea during the Bronze/Iron Age and a high level of individual mobility typical of cosmopolitan societies. Finally, we highlighted the role of the Roman Empire in shaping genetic and phenotypic changes that greatly impacted the Italian peninsula.

genomics↗

Echoes from the last Green Sahara: whole genome analysis of Fulani, a key population to unveil the genetic evolutionary history of Africa

BackgroundThe Sahelian Fulani are the largest nomadic pastoral ethnic group. Their origins are still largely unknown and their Eurasian genetic component is usually explained by recent admixture events with northern African groups. However, it has also been proposed that Fulani may be the descendants of ancient groups settled in the Sahara during its last Green phase (12000-5000 BP), as also suggested by Y chromosome results. ResultsWe produced 23 high-coverage (30 x) whole genomes from Fulani individuals from 8 Sahelian countries, plus 17 samples from other African groups and 3 Europeans as controls, for a total of 43 new whole genome sequences. These data have been compared with 814 published modern whole genomes and analyzed together with relevant published ancient individuals (for a total of > 1800 samples). These analyses showed that the non-sub-Saharan genetic ancestry component of Fulani cannot be only explained by recent admixture events, but it could be shaped at least in part by older events by events more ancient than previously reported, possibly tracing its origin to the last Green Sahara. ConclusionsAccording to our results, Fulani may be the descendants of Saharan cattle herders settled in that area during the last Green Sahara. The exact ancestry composition of such ghost Saharan population(s) cannot be completely unveiled from modern genomes only, but the joint analysis with the available African ancient samples suggested a similarity between ancient Saharans and Late Neolithic Moroccans.

genetics↗

Intrinsic excitability in layer IV-VI anterior insula to basolateral amygdala projection neurons encodes the confidence of taste valence

Avoiding potentially harmful, and consuming safe food is crucial for the survival of living organisms. However, sensory information can change its valence following conflicting experiences. Novelty and aversiveness are the two crucial parameters defining the currently perceived valence of taste. Importantly, the ability of a given taste to serve as CS in conditioned taste aversion (CTA) is dependent on its valence. Activity in anterior insula (aIC) layer IV-VI pyramidal neurons projecting to the basolateral amygdala (BLA) is correlative and necessary for CTA learning and retrieval, as well as the expression of neophobia towards novel tastants, but not learning taste familiarity. Yet, the cellular mechanisms underlying the updating of taste valence representation in this specific pathway are poorly understood. Here, using retrograde viral tracing and whole cell patch-clamp electrophysiology in trained mice, we demonstrate that the intrinsic properties of deep-lying layer IV-VI, but not superficial layer I-III aIC-BLA neurons, are differentially modulated by both novelty and valence, reflecting the subjective predictability of taste valence arising from prior experience. These correlative changes in the profile of intrinsic properties of LIV-VI aIC-BLA neurons were detectable following both simple taste experiences, as well as following memory retrieval, extinction learning and reinstatement.

neuroscience↗

A Cre-amplifier to generate and detect genetic mosaics in vivo

Cre-Lox manipulation is the gold standard for cell-specific expression or knockout of selected genes. However, it is not unusual to deal with conditions of low Cre expression or transient activation, which can often go undetected by conventional Cre-reporters. We designed Beatrix, a general-purpose tool specifically devised to amplify weak Cre recombinase activity, and we used it to develop a powerful approach for the in vivo generation and detection of sparse mosaics of mutant and wild type cells.

neuroscience↗

Genetic analysis of Sephardic ancestry in the Iberian Peninsula

The Sephardim are a major Jewish ethnic division whose origins can be traced back to the Iberian Peninsula. We used genome-wide SNP data to investigate the degree of Sephardic admixture in seven populations from the Iberian Peninsula and surrounding regions in the aftermath of their religious persecution starting in the late 14th century. To this end, we used Eastern Mediterranean (from South Italy, Greece and Israel) and North African (Tunisian and Moroccan) populations as proxies for the major ancestral components found in the target populations and carried out unlinked- and linked-marker analyses on the available genetic data. We report evidence of Sephardic ancestry in some of our Iberian samples, as well as in North Italy and Tunisia. We find the Sephardic admixture to be more recent relative to the Berber admixture following an out-of-Iberia geographic dispersal, suggesting Sephardic gene flow from Spain outwards. We also report some of the challenges in assigning Sephardic ancestry to potentially admixed individuals due to the lack of a clear genetic signature.

genomics↗