Li, J. et al. Nat. Biotechnol. 32, 834–841 (2014).

Sequencing surveys have provided a window into the microbial populations that call our bowels home. Researchers with the European Metagenomics of the Human Intestinal Tract (MetaHit) project now consolidate and expand the catalog of sequences available from the gut. Li et al. provide shotgun sequence from 249 new samples and combine these with existing data from over 1,000 European and US samples from MetaHit and the Human Microbiome Project as well as a large diabetes study from China, plus more than 500 sequenced gut bacterial genomes, generating an integrated gene catalog with nearly 1 million nonredundant gene sequences. The authors were able to identify microbial abundance patterns specific to different countries. The unprecedented size of this resource will allow better functional studies of gut microbes.