Search

Your search keyword '"Guichard, Etienne"' showing total 5 results
Start Over Author "Guichard, Etienne" Language english
5 results on '"Guichard, Etienne"'

4. Transposable Elements Activity is Positively Related to Rate of Speciation in Mammals

Author

Alessio Boattini, Marco Ricci, Cristian Taccioli, Etienne Guichard, Valentina Peona, Ricci, Marco, Peona, Valentina, Guichard, Etienne, Taccioli, Cristian, and Boattini, Alessio

Subjects
0301 basic medicine, Transposable element, Evolution, Speciation, Genome, Evolutionsbiologi, 03 medical and health sciences, Rate of speciation, Eutheria, Behavior and Systematics, Genetic algorithm, Genetics, Molecular Biology, Ecology, Evolution, Behavior and Systematics, High rate, Cold genome, Evolutionary Biology, biology, Ecology, Relative rate of speciation, Mammals evolution, Transposable elements, biology.organism_classification, Ecology, Evolution, Behavior and Systematic, 030104 developmental biology, Taxon, Order (biology), Evolutionary biology
Abstract

Transposable elements (TEs) play an essential role in shaping eukaryotic genomes and generating variability. Speciation and TE activity bursts could be strongly related in mammals, in which simple gradualistic models of differentiation do not account for the currently observed species variability. In order to test this hypothesis, we designed two parameters: the Density of insertion (DI) and the Relative rate of speciation (RRS). DI is the ratio between the number of TE insertions in a genome and its size, whereas the RRS is a conditional parameter designed to identify potential speciation bursts. Thus, by analyzing TE insertions in mammals, we defined the genomes as "hot" (high DI) and "cold" (low DI). Then, comparing TE activity among 29 taxonomical families of the whole Mammalia class, 16 intra-order pairs of mammalian species, and four superorders of Eutheria, we showed that taxa with high rates of speciation are associated with "hot" genomes, whereas taxa with low ones are associated with "cold" genomes. These results suggest a remarkable correlation between TE activity and speciation, also being consistent with patterns describing variable rates of differentiation and accounting for the different time frames of the speciation bursts. Correction in: Journal of Molecular Evolution, vol. 86, issue 5, pages 311-311. DOI: 10.1007/s00239-018-9850-zThe original version of the article unfortunately contained tagging error in Given and Surname of all the authors. This has been corrected with this erratum.WoS title: Transposable Elements Activity is Positively Related to Rate of Speciation in Mammals (vol 86, pg 303, 2018)

Published
2018

5. Ancient and recent admixture layers in Sicily and Southern Italy trace multiple migration routes along the Mediterranean.

Author

Sarno S, Boattini A, Pagani L, Sazzini M, De Fanti S, Quagliariello A, Gnecchi Ruscone GA, Guichard E, Ciani G, Bortolini E, Barbieri C, Cilli E, Petrilli R, Mikerezi I, Sineo L, Vilar M, Wells S, Luiselli D, and Pettener D

Abstract

The Mediterranean shores stretching between Sicily, Southern Italy and the Southern Balkans witnessed a long series of migration processes and cultural exchanges. Accordingly, present-day population diversity is composed by multiple genetic layers, which make the deciphering of different ancestral and historical contributes particularly challenging. We address this issue by genotyping 511 samples from 23 populations of Sicily, Southern Italy, Greece and Albania with the Illumina GenoChip Array, also including new samples from Albanian- and Greek-speaking ethno-linguistic minorities of Southern Italy. Our results reveal a shared Mediterranean genetic continuity, extending from Sicily to Cyprus, where Southern Italian populations appear genetically closer to Greek-speaking islands than to continental Greece. Besides a predominant Neolithic background, we identify traces of Post-Neolithic Levantine- and Caucasus-related ancestries, compatible with maritime Bronze-Age migrations. We argue that these results may have important implications in the cultural history of Europe, such as in the diffusion of some Indo-European languages. Instead, recent historical expansions from North-Eastern Europe account for the observed differentiation of present-day continental Southern Balkan groups. Patterns of IBD-sharing directly reconnect Albanian-speaking Arbereshe with a recent Balkan-source origin, while Greek-speaking communities of Southern Italy cluster with their Italian-speaking neighbours suggesting a long-term history of presence in Southern Italy.

Published
2017
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results