TY - JOUR T1 - The demographic history and mutational load of African hunter-gatherers and farmers JF - bioRxiv DO - 10.1101/131219 SP - 131219 AU - Marie Lopez AU - Athanasios Kousathanas AU - Hélène Quach AU - Christine Harmant AU - Patrick Mouguiama-Daouda AU - Jean-Marie Hombert AU - Alain Froment AU - George H. Perry AU - Luis B. Barreiro AU - Paul Verdu AU - Etienne Patin AU - Lluís Quintana-Murci Y1 - 2017/01/01 UR - http://biorxiv.org/content/early/2017/05/03/131219.abstract N2 - The distribution of deleterious genetic variation across human populations is a key issue in evolutionary biology and medical genetics. However, the impact of different modes of subsistence on recent changes in population size, patterns of gene flow, and deleterious mutational load remains unclear. Here, we report high-coverage exome sequencing data from various populations of rainforest hunter-gatherers and farmers from central Africa. We find that the recent demographic histories of hunter-gatherers and farmers differed considerably, with population collapses for hunter-gatherers and expansions for farmers, accompanied by increased gene flow. We show that purifying selection against deleterious alleles is of similar efficiency across African populations, in contrast with Europeans where we detect weaker purifying selection. Furthermore, the per-individual mutation load of rainforest hunter-gatherers is similar to that of farmers, under both additive and recessive models. Our results indicate that differences in the cultural practices and demographic regimes of African populations have not resulted in large differences in mutational burden, and highlight the beneficial role of gene flow in reshaping the distribution of deleterious genetic variation across human populations. ER -