The human microbiome plays an important role in human health and disease, and shotgun metagenomics provide a powerful method for studying the microbial communities it contains. However the resulting data are very big. We need new statistical and computational tools to make sense of the data and to identify important biological features.

Current methods provide only static features of microbial communities. The authors developed a new statistical method to study the growth dynamics of bacteria, which can effectively identify the bacteria that show differential growth rates between diseased and normal individuals, such as patients with inflammatory bowel disease. The results can potentially be used to develop disease treatments by inhibiting or promoting bacterial growth.