Nature Communications (Aug 2024)

Human genetic structure in Northwest France provides new insights into West European historical demography

  • Isabel Alves,
  • Joanna Giemza,
  • Michael G. B. Blum,
  • Carolina Bernhardsson,
  • Stéphanie Chatel,
  • Matilde Karakachoff,
  • Aude Saint Pierre,
  • Anthony F. Herzig,
  • Robert Olaso,
  • Martial Monteil,
  • Véronique Gallien,
  • Elodie Cabot,
  • Emma Svensson,
  • Delphine Bacq,
  • Estelle Baron,
  • Charlotte Berthelier,
  • Céline Besse,
  • Hélène Blanché,
  • Ozvan Bocher,
  • Anne Boland,
  • Stéphanie Bonnaud,
  • Eric Charpentier,
  • Claire Dandine-Roulland,
  • Claude Férec,
  • Christine Fruchet,
  • Simon Lecointe,
  • Edith Le Floch,
  • Thomas E. Ludwig,
  • Gaëlle Marenne,
  • Vincent Meyer,
  • Elisabeth Quellery,
  • Fernando Racimo,
  • Karen Rouault,
  • Florian Sandron,
  • Jean-Jacques Schott,
  • Lourdes Velo-Suarez,
  • Jade Violleau,
  • Eske Willerslev,
  • Yves Coativy,
  • Mael Jézéquel,
  • Daniel Le Bris,
  • Clément Nicolas,
  • Yvan Pailler,
  • Marcel Goldberg,
  • Marie Zins,
  • Hervé Le Marec,
  • Mattias Jakobsson,
  • Pierre Darlu,
  • Emmanuelle Génin,
  • Jean-François Deleuze,
  • Richard Redon,
  • Christian Dina

DOI
https://doi.org/10.1038/s41467-024-51087-1
Journal volume & issue
Vol. 15, no. 1
pp. 1 – 18

Abstract

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Abstract The demographical history of France remains largely understudied despite its central role toward understanding modern population structure across Western Europe. Here, by exploring publicly available Europe-wide genotype datasets together with the genomes of 3234 present-day and six newly sequenced medieval individuals from Northern France, we found extensive fine-scale population structure across Brittany and the downstream Loire basin and increased population differentiation between the northern and southern sides of the river Loire, associated with higher proportions of steppe vs. Neolithic-related ancestry. We also found increased allele sharing between individuals from Western Brittany and those associated with the Bell Beaker complex. Our results emphasise the need for investigating local populations to better understand the distribution of rare (putatively deleterious) variants across space and the importance of common genetic legacy in understanding the sharing of disease-related alleles between Brittany and people from western Britain and Ireland.