Among these genes, methylation status of multidrug resistance 1 (MDR1), fragile X mental retardation 1 (FMR1), CDH1 and GDNF gene was elevated, while methylation status of NOTCH3, CDH17, PAD14, TNFSF8, EPHX1, HOXV2, FRK etc. was decreased in inflamed mucosa in comparison with quiescent mucosa, indicating that histologic methylation profiles can serve as valuable surrogates to evaluate the disease activity of IBD. The gene discussed is FMR1; the disease is irritable bowel syndrome.