Given the raising evidence for a key role of CEACAM6 in the complex interaction of the mucosal immune system and intestinal bacteria, we next analyzed for potential epistasis between CEACAM6 SNPs (rs10415946, rs1805223 = p.Pro42Pro, rs4803507, rs4803508, rs11548735 = p.Gly239Val, rs7246116 = pHis260His, rs2701, rs10416839) and the three main CD-associated NOD2/CARD15 variants p.Arg702Trp (rs2066844), p.Gly908Arg (rs2066845), and p.Leu1007fsX1008 (rs2066847) which have previously shown to be strongly associated with CD and ileal disease localization. The gene discussed is NOD2; the disease is Cowden disease.