In their recent paper, Dart and colleagues performed an unprecedented in-depth study to characterize the colonic γδ TCR repertoire in healthy donors and IBD patients, and they investigated the impact of BTNL3 and BTNL8 on the selection of Vγ4 γδ intraepithelial cells (IEL).1 These studies were performed on a total of 173 colonic endoscopic biopsies including non-IBD controls, uninflamed gut from patients with confirmed IBD, and inflamed lesions from IBD patients. The gene discussed is BTNL8; the disease is inflammatory bowel disease.