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Traverso, L.

Publications and source records attributed to Traverso, L..

3 recordsLinked to original sources

Unveiling the complexity of post-Roman polity formation using ancient DNA

The transformation of the Roman world (4th-9th centuries CE) culminating in the dissolution of the Western Roman Empire in the 5th century marked a fundamental transition in European history. "Barbarian" groups and Roman provincial societies merged into enduring political frameworks in some places but not in others. Key questions persist regarding the regionally specific nature of this transformation. Here, we present one of the most densely sampled early medieval datasets to date, enabling the reconstruction of a post-Roman polity at an unprecedented micro-regional resolution. Our integrated genetic and archaeological analysis of two Roman-period (n=68) and five post-Roman (n=246) sites from the Little Hungarian Plain, a former Roman frontier region, reveals a significant increase in Northern European genetic ancestry, likely reflecting a large-scale population movement into the region. Moreover, while all post-Roman sites, dated to the time of the Langobard Kingdom, share similar genetic profiles, burial practices, and material culture, they display distinct patterns of social organization, especially regarding the role that biological relatedness played in each community. Our results suggest that distinct social hierarchies might have existed between sites, and their intensive connectivity probably formed the basis for regional-level organisation within the post-Roman polity. Our study provides a framework for investigating how new polities take shape after the collapse of major political systems. Applied more broadly, this approach can deepen our understanding of societal transformation across early medieval Europe and beyond, offering a richer and more nuanced view of the human past than ever before.

evolutionary biology↗

The Genetic History of the South Caucasus from the Bronze to the Early Middle Ages: 5000 years of genetic continuity despite high mobility

Archaeological and archaeogenetic studies have highlighted the pivotal role of the Caucasus region throughout prehistory, serving as a central hub for cultural, technological, and linguistic innovations. However, despite its dynamic history, the critical area between the Greater and Lesser Caucasus mountain ranges, mainly corresponding to modern-day Georgia, has received limited attention. Here, we generated an ancient DNA time transect consisting of 219 individuals with genome-wide data from 47 sites in this region, supplemented by 97 new radiocarbon dates. Spanning from the Early Bronze Age 5000 years ago to the so-called Migration Period that followed the fall of the Western Roman Empire, we document a largely persisting local gene pool that continuously assimilated migrants from Anatolia/Levant and the populations of the adjacent Eurasian steppe. More specifically, we observe these admixture events as early as the Middle Bronze Age. Starting with Late Antiquity (late first century AD), we also detect an increasing number of individuals with more southern ancestry, more frequently associated with urban centers - landmarks of the early Christianization in eastern Georgia. Finally, in the Early Medieval Period starting 400 AD, we observe genetic outlier individuals with ancestry from the Central Eurasian steppe, with artificial cranial deformations (ACD) in several cases. At the same time, we reveal that many individuals with ACD descended from native South Caucasus groups, indicating that the local population likely adopted this cultural practice.

genetics↗

Transcriptomic modulation in response to an intoxication with deltamethrin in Triatoma infestans, vector of Chagas disease

BackgroundTriatoma infestans is the main vector of Chagas disease in the Southern Cone. The resistance to pyrethroid insecticides developed by populations of this species impairs the effectiveness of vector control campaigns in wide regions of Argentina. The study of the global transcriptomic response to pyrethroid insecticides is important to deepen the knowledge about detoxification in triatomines. Methodology and findingsWe used RNA-Seq to explore the early transcriptomic response of T. infestans after intoxication with deltamethrin. We were able to assemble a complete transcriptome of this vector and found evidence of differentially expressed genes belonging to diverse families such as chemosensory and odorant-binding proteins, ABC transporters and heat-shock proteins. Moreover, genes related to transcription and translation, energetic metabolism and cuticle rearrangements were also modulated. Finally, we characterized the repertoire of previously uncharacterized detoxification-related gene families in T. infestans and Rhodnius prolixus. Conclusions and significanceOur work contributes to the understanding of the detoxification response in vectors of Chagas disease. Given the absence of genomic information from T. infestans, the analysis presented here constitutes a resource for molecular and physiological studies in this species. The results increase the knowledge on detoxification processes in vectors of Chagas disease, and provide relevant information to explore new potential insecticide resistance mechanisms in these insects. Author summaryChagas disease affects millions of people worldwide. In the Southern Cone, the development of pyrethroid resistant populations from T. infestans is related to vector persistence and affects the efficiency of vector control campaigns. Several studies have explored the causes of insecticide resistance in T. infestans populations. However, the global transcriptomic response after insecticide treatment has not been analyzed in this species so far. In this study, we obtained transcriptomic information which allowed us to characterize important gene families despite the absence of genomic information. Furthermore, we performed a quantitative analysis of gene expression after deltamethrin intoxication. The results provided here increase the knowledge on detoxification processes in vectors of Chagas disease, which is essential for the design of new vector control strategies.

genomics↗