In a series of immuno-histochemical studies lysozyme was found up-regulated in many organs of the GI undergoing chronic inflammation, such as Barrett’s oesophagitis, chronic gastritis, gluten-induced atrophic duodenitis (coeliac disease), collagenous colitis, lymphocytic colitis, ulcerative colitis (UC), and Crohn’s colitis [7,8,9,10], strongly suggesting that the associated bacterial flora plays an important role in the expression of this antimicrobial enzyme. The gene discussed is LYZ; the disease is lymphocytic colitis.