We previously examined the effects of the NOD2 and ATG16L1 polymorphisms on ileal microbial composition in 1) ileal CD subjects undergoing initial ileal resection, 2) IBD colitis without ileitis (predominantly ulcerative colitis) subjects and 3) subjects without inflammatory bowel disease (non-IBD) [2–4]. This evidence concerns the gene NOD2 and inflammatory bowel disease.