IRGM and inflammatory bowel disease: Recent accumulating evidence showed a close association between autophagy in the intestinal epithelial cells and inflammatory bowel diseases (IBDs); indeed, single-nucleotide polymorphisms (SNPs) within two autophagy-related genes, autophagy-related 16-like 1(ATG16L1) and the immunity-related GTPase family M (IRGM), are important loci for IBD pathogenesis [25, 26].