Genes are only one part of how IBD arises. The other parts are less clear, but equally important in the quest to understand how to prevent and treat these conditions. A new report, Gut microbiota and inflammatory bowel disease, published by the Gut Microbiota for Health Experts Exchange platform and edited by Professors Philippe Marteau and Harry Sokol, gives an overview of the new theories on the disordered physiology of IBD.