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Seguin-Orlando, A.

Publications and source records attributed to Seguin-Orlando, A..

3 recordsLinked to original sources

A minimal hybridization capture system for the parallel enrichment and cost-effective detection of ancient human pathogens

The preservation of ancient DNA in archaeological remains enables identification of past disease agents. However, pathogen DNA is typically highly diluted by host and environmental DNA, limiting detection. Here, we present a proof-of-concept study using in-solution hybridization capture to improve detectability of a pre-defined set of 12 pathogens. We validate the method by detecting Yersinia pestis, the plague agent, in six individuals from 17th and 18th century French plague cemeteries with minimal sequencing. Expanding our probe set to target biomarkers of virtually any pathogen of interest offers a powerful tool for tracking the prevalence of infectious diseases in ancient populations.

molecular biology↗

A late Neanderthal reveals genetic isolation in their populations before extinction

Neanderthal genomes have been recovered from sites across Eurasia, painting an increasingly complex picture of their populations structure, mostly indicating that late European Neanderthals belonged to a single metapopulation with no significant evidence of deep population structure. Here we report the discovery of a late Neanderthal individual, nicknamed "Thorin", from Grotte Mandrin in Mediterranean France, and his genome. These dentognathic fossils, including a rare example of distomolars, are associated with a rich archeological record of their final technological traditions in this region [~]50-42 thousand years ago. Thorins genome reveals a deep divergence with other late Neanderthals. Thorin belonged to a population with small group size that showed no genetic introgression with other known late European Neanderthals, revealing genetic isolation of his lineage despite them living in neighboring regions. These results have important implications for resolving competing hypotheses about causes of the Neanderthals disappearance. One Sentence SummaryA new French Neanderthal fossil and its genome reveal complex population dynamics during the past 100,000 years.

genomics↗

Ancient Genomics Reveals Four Prehistoric Migration Waves into Southeast Asia

Two distinct population models have been put forward to explain present-day human diversity in Southeast Asia. The first model proposes long-term continuity (Regional Continuity model) while the other suggests two waves of dispersal (Two Layer model). Here, we use whole-genome capture in combination with shotgun sequencing to generate 25 ancient human genome sequences from mainland and island Southeast Asia, and directly test the two competing hypotheses. We find that early genomes from Hoabinhian hunter-gatherer contexts in Laos and Malaysia have genetic affinities with the Onge hunter-gatherers from the Andaman Islands, while Southeast Asian Neolithic farmers have a distinct East Asian genomic ancestry related to present-day Austroasiatic-speaking populations. We also identify two further migratory events, consistent with the expansion of speakers of Austronesian languages into Island Southeast Asia ca. 4 kya, and the expansion by East Asians into northern Vietnam ca. 2 kya. These findings support the Two Layer model for the early peopling of Southeast Asia and highlight the complexities of dispersal patterns from East Asia.

evolutionary biology↗