CNTNAP2 and inflammatory bowel disease: Moreover, many IBD risk genes, including BTBD8 (BTB Domain Containing 8), GRP (Gastrin-Releasing Peptide), JAZF1 (Juxtaposed with Another Zinc Finger Protein 1), NDFIP1 (Nedd4 Family-Interacting Protein 1), PLA2R1 (Phospholipase A2 Receptor 1), and CNTNAP2 (Contactin-Associated Protein 2), were found to be enriched in the ENS, which suggests a potential role of the ENS in IBD pathogenesis [41].