After a postdoctoral training in epidemiological genetics at the Necker Hospital (France), he joined Institut Pasteur as a CNRS Research Scientist. He is a population geneticist whose main interests range from the study of past human demography, with a focus on Africa, to the methodological aspects of demographic inference, and, more recently, systems immunology. One of his main research interests is the occurrence and extent of admixture between modern human populations and its potential adaptive nature.