This discovery reshapes understanding of IBD and opens the way to targeted approaches to diagnosis and treatment in a subset of patients. The findings suggest that inflammatory bowel disease is not a single condition, but a group of biologically distinct diseases driven by different underlying mechanisms.

In a study published today in the New England Journal of Medicine, researchers analyzed more than 4,900 patients with IBD and made two major discoveries: first, that a substantial subset of patients show autoimmune responses to one of the guardians of the immune system, interleukin-10 (IL-10), which leads to uncontrolled inflammation; and second, that this damaging immune response is the mechanism for one of the strongest known genetic risk factors for IBD.