12 results on '"Francois-Xavier Ricaut"'
Search Results
2. A genomic history of Aboriginal Australia.
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Anna-Sapfo Malaspinas, Michael C. Westaway, Craig Muller, Vitor C. Sousa, Oscar Lao, Isabel Alves, Anders Bergström, Georgios Athanasiadis, Jade Yu Cheng, Jacob E. Crawford, Tim H. Heupink, Enrico Macholdt, Stephan Peischl, Simon Rasmussen, Stephan Schiffels, Sankar Subramanian, Joanne L. Wright, Anders Albrechtsen, Chiara Barbieri, Isabelle Dupanloup, Anders Eriksson, Ashot Margaryan, Ida Moltke, Irina Pugach, Thorfinn Sand Korneliussen, Ivan P. Levkivskyi, José Víctor Moreno-Mayar, Shengyu Ni, Fernando Racimo, Martin Sikora, Yali Xue, Farhang A. Aghakhanian, Nicolas Brucato, Søren Brunak, Paula F. Campos, Warren Clark, Sturla Ellingvåg, Gudjugudju Fourmile, Pascale Gerbault, Darren Injie, George Koki, Matthew Leavesley, Betty Logan, Aubrey Lynch, Elizabeth A. Matisoo-Smith, Peter J. McAllister, Alexander J. Mentzer, Mait Metspalu, Andrea B. Migliano, Les Murgha, Maude E. Phipps, William Pomat, Doc Reynolds, Francois-Xavier Ricaut, Peter Siba, Mark G. Thomas, Thomas Wales, Colleen Ma'run Wall, Stephen J. Oppenheimer, Chris Tyler-Smith, Richard Durbin, Joe Dortch, Andrea Manica, Mikkel H. Schierup, Robert A. Foley, Marta Mirazón Lahr, Claire Bowern, Jeffrey D. Wall, Thomas Mailund, Mark Stoneking, Rasmus Nielsen, Manjinder S. Sandhu, Laurent Excoffier, David M. Lambert, and Eske Willerslev
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- 2016
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3. Tissue- and ethnicity-independent hypervariable DNA methylation states show evidence of establishment in the early human embryo
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Maria Derakhshan, Noah J Kessler, Miho Ishida, Charalambos Demetriou, Nicolas Brucato, Gudrun E Moore, Caroline H D Fall, Giriraj R Chandak, Francois-Xavier Ricaut, Andrew M Prentice, Garrett Hellenthal, Matt J Silver, Evolution et Diversité Biologique (EDB), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Centre National de la Recherche Scientifique (CNRS), Medical Research Council, Human Genetics Division [Singapore], Genome Institute of Singapore (GIS), and University College of London [London] (UCL)
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Tissue-and ethnicity-independent ,Illumina 450K array ,Hypervariable DNA methylation ,Genetics ,Early embryo ,Humans ,Reproducibility of Results ,Systemic inter-individual variation ,[SDE.BE]Environmental Sciences/Biodiversity and Ecology ,DNA Methylation - Abstract
We analysed DNA methylation data from 30 datasets comprising 3474 individuals, 19 tissues and 8 ethnicities at CpGs covered by the Illumina450K array. We identified 4143 hypervariable CpGs (‘hvCpGs’) with methylation in the top 5% most variable sites across multiple tissues and ethnicities. hvCpG methylation was influenced but not determined by genetic variation, and was not linked to probe reliability, epigenetic drift, age, sex or cell heterogeneity effects. hvCpG methylation tended to covary across tissues derived from different germ-layers and hvCpGs were enriched for proximity to ERV1 and ERVK retrovirus elements. hvCpGs were also enriched for loci previously associated with periconceptional environment, parent-of-origin-specific methylation, and distinctive methylation signatures in monozygotic twins. Together, these properties position hvCpGs as strong candidates for studying how stochastic and/or environmentally influenced DNA methylation states which are established in the early embryo and maintained stably thereafter can influence life-long health and disease.
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- 2022
4. Positive selection in the genomes of two Papua New Guinean populations at distinct altitude levels
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Mathilde André, Nicolas Brucato, Georgi Hudjasov, Vasili Pankratov, Danat Yermakovich, Francesco Montinaro, Rita Kreevan, Jason Kariwiga, John Muke, Anne Boland, Jean-François Deleuze, Vincent Meyer, Nicholas Evans, Murray P. Cox, Matthew Leavesley, Michael Dannemann, Tõnis Org, Mait Metspalu, Mayukh Mondal, and François-Xavier Ricaut
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Science - Abstract
Abstract Highlanders and lowlanders of Papua New Guinea have faced distinct environmental stress, such as hypoxia and environment-specific pathogen exposure, respectively. In this study, we explored the top genomics regions and the candidate driver SNPs for selection in these two populations using newly sequenced whole-genomes of 54 highlanders and 74 lowlanders. We identified two candidate SNPs under selection - one in highlanders, associated with red blood cell traits and another in lowlanders, which is associated with white blood cell count – both potentially influencing the heart rate of Papua New Guineans in opposite directions. We also observed four candidate driver SNPs that exhibit linkage disequilibrium with an introgressed haplotype, highlighting the need to explore the possibility of adaptive introgression within these populations. This study reveals that the signatures of positive selection in highlanders and lowlanders of Papua New Guinea align closely with the challenges they face, which are specific to their environments.
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- 2024
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5. Exploration de l’architecture génétique et des facteurs environnementaux influençant la diversité pigmentaire de la peau en Papouasie-Nouvelle-Guinée
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Adeline Morez, Nicolas Brucato, Georgi Hudjashov, Christopher Kinipi, Matthew Leavesley, and François-Xavier Ricaut
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History of Civilization ,CB3-482 - Published
- 2023
6. Polymorphisme des systèmes de groupe sanguin en Papouasie Nouvelle-Guinée
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Benjamin Tournan, Adeline Morez, Stephane Mazières, Christopher Kinipi, Matthew Leavesley, Nicolas Brucato, and François-Xavier Ricaut
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History of Civilization ,CB3-482 - Published
- 2023
7. Denisovan introgression has shaped the immune system of present-day Papuans.
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Davide M Vespasiani, Guy S Jacobs, Laura E Cook, Nicolas Brucato, Matthew Leavesley, Christopher Kinipi, François-Xavier Ricaut, Murray P Cox, and Irene Gallego Romero
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Genetics ,QH426-470 - Abstract
Modern humans have admixed with multiple archaic hominins. Papuans, in particular, owe up to 5% of their genome to Denisovans, a sister group to Neanderthals whose remains have only been identified in Siberia and Tibet. Unfortunately, the biological and evolutionary significance of these introgression events remain poorly understood. Here we investigate the function of both Denisovan and Neanderthal alleles characterised within a set of 56 genomes from Papuan individuals. By comparing the distribution of archaic and non-archaic variants we assess the consequences of archaic admixture across a multitude of different cell types and functional elements. We observe an enrichment of archaic alleles within cis-regulatory elements and transcribed regions of the genome, with Denisovan variants strongly affecting elements active within immune-related cells. We identify 16,048 and 10,032 high-confidence Denisovan and Neanderthal variants that fall within annotated cis-regulatory elements and with the potential to alter the affinity of multiple transcription factors to their cognate DNA motifs, highlighting a likely mechanism by which introgressed DNA can impact phenotypes. Lastly, we experimentally validate these predictions by testing the regulatory potential of five Denisovan variants segregating within Papuan individuals, and find that two are associated with a significant reduction of transcriptional activity in plasmid reporter assays. Together, these data provide support for a widespread contribution of archaic DNA in shaping the present levels of modern human genetic diversity, with different archaic ancestries potentially affecting multiple phenotypic traits within non-Africans.
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- 2022
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8. Phenotypic differences between highlanders and lowlanders in Papua New Guinea.
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Mathilde André, Nicolas Brucato, Sébastien Plutniak, Jason Kariwiga, John Muke, Adeline Morez, Matthew Leavesley, Mayukh Mondal, and François-Xavier Ricaut
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Medicine ,Science - Abstract
ObjectivesAltitude is one of the most demanding environmental pressures for human populations. Highlanders from Asia, America and Africa have been shown to exhibit different biological adaptations, but Oceanian populations remain understudied [Woolcock et al., 1972; Cotes et al., 1974; Senn et al., 2010]. We tested the hypothesis that highlanders phenotypically differ from lowlanders in Papua New Guinea, as a result of inhabiting the highest mountains in Oceania for at least 20,000 years.Materials and methodsWe collected data for 13 different phenotypes related to altitude for 162 Papua New Guineans living at high altitude (Mont Wilhelm, 2,300-2,700 m above sea level (a.s.l.) and low altitude (Daru, ResultsSix phenotypes were significantly different between Papua New Guinean highlanders and lowlanders. Highlanders show shorter height (p-value = 0.001), smaller waist circumference (p-value = 0.002), larger Forced Vital Capacity (FVC) (p-value = 0.008), larger maximal (p-value = 3.20e -4) and minimal chest depth (p-value = 2.37e -5) and higher haemoglobin concentration (p-value = 3.36e -4).DiscussionOur study reports specific phenotypes in Papua New Guinean highlanders potentially related to altitude adaptation. Similar to other human groups adapted to high altitude, the evolutionary history of Papua New Guineans appears to have also followed an adaptive biological strategy for altitude.
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- 2021
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9. Genomic admixture tracks pulses of economic activity over 2,000 years in the Indian Ocean trading network
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Nicolas Brucato, Pradiptajati Kusuma, Philippe Beaujard, Herawati Sudoyo, Murray P. Cox, and François-Xavier Ricaut
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Medicine ,Science - Abstract
Abstract The Indian Ocean has long been a hub of interacting human populations. Following land- and sea-based routes, trade drove cultural contacts between far-distant ethnic groups in Asia, India, the Middle East and Africa, creating one of the world’s first proto-globalized environments. However, the extent to which population mixing was mediated by trade is poorly understood. Reconstructing admixture times from genomic data in 3,006 individuals from 187 regional populations reveals a close association between bouts of human migration and trade volumes during the last 2,000 years across the Indian Ocean trading system. Temporal oscillations in trading activity match phases of contraction and expansion in migration, with high water marks following the expansion of the Silk Roads in the 5th century AD, the rise of maritime routes in the 11th century and a drastic restructuring of the trade network following the arrival of Europeans in the 16th century. The economic fluxes of the Indian Ocean trade network therefore directly shaped exchanges of genes, in addition to goods and concepts.
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- 2017
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10. Populations anciennes et ADN ancien: état actuel de la question
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Christine Keyser-Tracqui, Francois-Xavier Ricaut, Eric Crubézy, Bertrand Ludes, RICAUT, FRANCOIS-XAVIER, and Centre National de la Recherche Scientifique (CNRS)
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[SHS.ANTHRO-BIO]Humanities and Social Sciences/Biological anthropology ,[SHS.ANTHRO-BIO] Humanities and Social Sciences/Biological anthropology - Abstract
International audience; Les possibilités offertes par la biologie moléculaire dans le domaine de l'anthropologie sont aujourd'hui largement reconnues. Après un rappel très succinct des marqueurs utilisés pour étudier l'ADN extrait de tissus anciens, cet article cherche à souligner les limites et les difficultés inhérentes à l'analyses de molécules dégradées et se propose de faire le point sur l'intérêt d'une approche moléculaire en anthropologie au travers d'exemples issus de la littérature.
11. Tracing Arab-Islamic inheritance in Madagascar: study of the Y-chromosome and mitochondrial DNA in the Antemoro.
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Mélanie Capredon, Nicolas Brucato, Laure Tonasso, Valérie Choesmel-Cadamuro, François-Xavier Ricaut, Harilanto Razafindrazaka, Andriamihaja Bakomalala Rakotondrabe, Mamisoa Adelta Ratolojanahary, Louis-Paul Randriamarolaza, Bernard Champion, and Jean-Michel Dugoujon
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Medicine ,Science - Abstract
Madagascar is located at the crossroads of the Asian and African worlds and is therefore of particular interest for studies on human population migration. Within the large human diversity of the Great Island, we focused our study on a particular ethnic group, the Antemoro. Their culture presents an important Arab-Islamic influence, but the question of an Arab biological inheritance remains unresolved. We analyzed paternal (n=129) and maternal (n=135) lineages of this ethnic group. Although the majority of Antemoro genetic ancestry comes from sub-Saharan African and Southeast Asian gene pools, we observed in their paternal lineages two specific haplogroups (J1 and T1) linked to Middle Eastern origins. This inheritance was restricted to some Antemoro sub-groups. Statistical analyses tended to confirm significant Middle Eastern genetic contribution. This study gives a new perspective to the large human genetic diversity in Madagascar.
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- 2013
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12. In search of Asian Malagasy ancestors in Indonesia
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Kusuma, Pradiptajati, Anthropologie Moléculaire et Imagerie de Synthèse (AMIS), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS), Université Paul Sabatier - Toulouse III, Francois-Xavier Ricaut, Thierry Letellier, Centre National de la Recherche Scientifique (CNRS)-Université Toulouse III - Paul Sabatier (UT3), and Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées
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Indonésie ,Chromosome Y ,Indonesia ,MtDNA ,Malagasy ,Genome-wide SNP ,Malgache ,ADNmt ,SNP génome ,[SHS.ANTHRO-SE]Humanities and Social Sciences/Social Anthropology and ethnology ,Y-chromosome ,Migration - Abstract
Indonesia hosts a wide range of linguistic, ethnic and genetic diversity, comprising ~600 ethnic groups and 700 living languages. Indonesia has facilitated the last substantial wave of human migration was the Austronesian dispersal ~5,000 years ago, which is thought to have originated in Taiwan. Its influence spread through Philippines and Indonesia, ultimately impacting a wide geographical area, from Remote Oceania in the east and to Madagascar in the west. Despite considerable genetic research on the eastward Austronesian expansion, there is little equivalent research on the western edge, leaving major issues unresolved regarding the settlement of Madagascar. Based on cultural and biological studies, it has been suggested that Indonesian peoples played a major role in the colonization of Madagascar from around the mid-first millennium CE (Current Era). However, poor geographical coverage of Indonesian populations has prevented the Indonesian source populations from being identified. Here, I performed human population genetic studies on 12 new Indonesian populations, which were a priori expected to shed light on the westward migration of Austronesians across the Indian Ocean. This includes the Ma'anyan ethnic group from Southeast Borneo, who are the closest linguistic siblings to modern Malagasy. Using different genetic markers (Y-chromosome SNPs, mitochondrial DNA and genome-wide SNPs), my research has improved the description of Indonesian genetic diversity, and investigated the genetic links between Indonesia and Madagascar. Results Uniparental markers (Y-chromosome and mtDNA) analyses suggest that Malagasy derive from multiple regional sources in Indonesia, with a focus on southeastern Borneo, southern Sulawesi and the Lesser Sunda islands. Interestingly, the Ma'anyan share limited paternal and maternal lineages with the Malagasy, despite their linguistic connection. Furthermore, combining SNP frequency and haplotype-based analyses from autosomal genome-wide data, it was confirmed that the genetic diversity of the Ma'anyan does not match the Asian ancestry of the Malagasy. However, by focusing on Southeast Borneo populations, strong support was found for an origin of the Asian ancestry of Malagasy among the people of Banjar, an admixed population of Ma'anyan and Malay, likely resulting from trading activities by the Malay Empire in Southeast Borneo, and later continuing across the Indian Ocean arena. These results increase our understanding of genetic diversity across Indonesia by 1) identifying the unique and undiscovered Austronesian genetic component carried by the Ma'anyan, which occurs at low levels across Island Southeast Asia and suggests a more complex model for the Austronesian expansion in this region, and 2) describing the role played by sea-nomads in structuring genetic diversity and exchanges in central Indonesia, thus revealing the complex genetic history of populations living this rare nomadic lifestyle.; L'Indonésie a été l'objet de la dispersion Austronésienne qui a débuté il y a environ 5000 ans depuis Taiwan, se propager à travers les Philippines et l'Indonésie, puis toucher l'Océanie à l'est, et à Madagascar à l'ouest. Malgré de nombreuses recherches en génétique sur la dispersion Austronésienne vers l'est, il y a très peu de données sur la dispersion vers l'ouest, laissant sans réponse de nombreuses questions, liées notamment au peuplement de Madagascar. Reposant sur l'analyse des données culturelles et biologiques, les populations d'Indonésie semblent avoir joué un rôle majeur dans la colonisation de Madagascar, le premier millénaire de notre ère. Cependant, le peu de populations Indonésiennes étudiées à ce jour n'a pas permis jusqu'à présent d'identifier la population indonésienne source. Dans ce présent travail, j'ai réalisé des études en génétique des populations de 12 populations Indonésiennes, qui à priori devraient éclairer l'histoire des migrations austronésiennes dans l'Océan Indien. Parmi elles sont inclus le Ma'anyan du sud-est de Bornéo qui sont les plus proches linguistiquement des Malgaches. En utilisant différents marqueurs génétiques, ma recherche a amélioré nos connaissances de la diversité génétique Indonésienne, et du lien génétique entre l'Indonésie et Madagascar. Résultats L'analyse des marqueurs uniparentaux (chr-Y et ADNmt) suggère que les Malgaches proviennent de plusieurs régions d'Indonésie, avec un lien privilégié avec le sud-est de Bornéo, le sud de Sulawesi et les îles de la Sonde. Etonnamment, les Ma'anyan partagent un nombre limité de lignées paternelles et maternelles avec les Malgaches, malgré leur proximité linguistique. Par ailleurs, en combinant l'analyse de fréquences des SNPs et l'analyse haplotypique à partir des données autosomales, il a été confirmé que la diversité génétique des Ma'anyan ne correspond pas à l'ancestralité asiatique des Malgaches. Cependant, en centrant l'analyse sur les populations du sud-est de Bornéo, l'origine de l'ancestralité asiatique des Malgaches est ancrée dans la population Banjar, un mélange de population Ma'anyan et Malaise, résultat des activités commerciales de l'empire Malais dans le sud-est de Bornéo, qui se sont poursuivies à travers l'océan Indien. Par ailleurs nos résultats ont aussi permis d'accroitre notre compréhension de la diversité génétique de l'Indonésie en identifiant (1) une nouvelle composante génétique austronésienne présente chez les Ma'anyan, et retrouvée à faible fréquence à travers l'Asie du Sud-Est, suggérant une plus grande complexité du modèle d'expansion austronésien dans la région et (2) le rôle joué par les nomades de la mer dans la structuration de la diversité génétique et les échanges entre populations dans l'Indonésie, soulignant l'histoire génétique complexe de populations suivant un mode de vie nomade.
- Published
- 2017
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