SMAD3 and inflammatory bowel disease: They are significantly enriched in genes from the top 20 IBD-associated genes (‘top genes’ list [15], 3/20 genes; CARD9, SMAD3, and NOD2; OR 4.7, P = 0.03), but not with broader sets of genes previously associated with IBD (10/366 IBD-associated genes from our ‘extensive’ list and 4/242 GWAS loci [11] are contained in these ROH).