In a paper published online in advance in Nature this week, a team led by investigators at the Washington University School of Medicine presents an evaluation of how gut microbiomes differ among human populations. Based on its characterization of bacterial species in fecal samples from 531 individuals — from the Amazonas of Venezuela, rural Malawi, and US metropolitan areas — as well as the gene content of 110 of those individuals, the team identified "shared features of the functional maturation of the gut microbiome ...