A study by Dharmani et al showed that Fusobacterium nucleatum (a normal inhabitant of the human mouth and gut) derived from the inflamed intestines of Crohn's disease patients evoked significantly greater gene expression of mucin and tumor necrosis factor alpha gene than other bacteria isolated from the non-inflamed gut in human colonic epithelial cells [47]. The gene discussed is MUC5AC; the disease is Crohn disease.