RT Journal Article
SR Electronic
T1 The demographic history and mutational load of African hunter-gatherers and farmers
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 131219
DO 10.1101/131219
A1 Marie Lopez
A1 Athanasios Kousathanas
A1 Hélène Quach
A1 Christine Harmant
A1 Patrick Mouguiama-Daouda
A1 Jean-Marie Hombert
A1 Alain Froment
A1 George H. Perry
A1 Luis B. Barreiro
A1 Paul Verdu
A1 Etienne Patin
A1 Lluís Quintana-Murci
YR 2017
UL http://biorxiv.org/content/early/2017/05/03/131219.abstract
AB 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.