Overcoming a barrier to IBD Inflammatory bowel disease (IBD) is a group of disorders linked to inflammation of the gastrointestinal tract. Colitis is a type of IBD that affects the inner lining of the colon and has been linked to a gene known as C1orf106 . Mohanan et al. found that C1orf106 encodes a protein that stabilizes the integrity of epithelial junctions and enhances barrier defense (see the Perspective by Citi). IBD-associated mutations in C1orf106 lead to greater cytohesin-1 protein levels, changes in E-cadherin localization, and enhanced susceptibility to intestinal pathogens. Modulation of C1orf106 may thus hold promise for treating colitis and other IBDs. Science , this issue p. 1161 ; see also p. 1097