here - 5th International Conference on Bantu Languages

WS3
Oral or Poster in WorkShop 3:
Genomes of western and eastern Pygmies reveal early admixture with
expanding Bantus
Etienne Patin 1 , Katie Siddle 1 , Hélène Quach 1 , Christine Harmant 1 , Guillaume Laval 1 , Noémie Becker 2 ,
Simon Gravel 3 , Béatrice Régnault 4 , Laure Lemée 4 , Jean-Marie Hombert 5 , Lolke Van der Veen 5 , Alain
Froment 2 , Luis Barreiro 6 , Nathaniel J. Dominy 7 , George Perry 8 , Paul Verdu 2 , Evelyne Heyer 2 , Lluís
Quintana-Murci 1
1 Human Evolutionary Genetics, CNRS URA3012, Institut Pasteur, Paris, France; 2 Ecoanthropology and
Ethnobiology, CNRS/MNHN/Université P7 UMR 5145, Paris, France; 3 Department of Genetics, Stanford
University, Stanford, USA; 4 Genotyping Platform, Institut Pasteur, Paris, France; 5 Département de Dynamique
du Langage, CNRS UMR 5596, Université Lumière-Lyon 2, Lyon, France; 6 Université de Montréal, Centre de
recherche CHU Sainte-Justine, Montréal, Canada; 7 Anthropology department, Dartmouth college, Hanover,
USA; 8 Department of Human Genetics, University of Chicago, Chicago, USA
Hunter-gathering Pygmies and food-producing Bantu villagers have coexisted along the central
African belt for hundreds of years. Their present-day complex relationships result from long-term
socio-cultural and economic exchanges. The degree at which these interactions impacted the history of
admixture of each population group remains nevertheless largely unknown. To shed new light on these
neglected aspects of the early African history, we genotyped one million markers in the entire genome
of a large sample of 327 individuals from eight Pygmy and non-Pygmy Bantu populations of both
western and eastern Africa. Population structure analyses revealed a clear isolation between Pygmies
and farmers, western and eastern Pygmies, and more surprisingly, between groups of eastern Pygmies.
Despite strong isolation between hunter-gat<strong>here</strong>rs and farmers stemming from cultural taboos, our
results clearly showed that genetic admixture has continuously occurred between the two
communities. We estimated that historical gene flow started as early as 4,000 years ago, concomitant
with the first Bantu expansions. Interestingly, the Pygmy populations who were first reached by
expanding Bantu-speakers show today higher stature, and stronger social integration and levels of
admixture with neighboring farmers, with respect to other Pygmy groups. Our study provides the first
genetic evidence that farmers’ expansions in Africa did not lead to the endangerment of autochthonous
hunter-gat<strong>here</strong>rs, but rather to the establishment of early genetic exchanges accompanying complex
socio-cultural interactions.