We found that five antibacterial peptide genes, defensins DEFA5 and DEFA6 (normally expressed in small intestine21 and Paneth cells) and c-lectins REG1A, REG1B, and REG3A (normally expressed in pancreas and small intestine21) were highly upregulated in IBD and at the same time showed extreme variance across UC and CD subjects (Fig. 2d). Here, REG1A is linked to inflammatory bowel disease.