According to several genome-wide association study (GWAS) studies conducted in 2007, the mutation of some autophagy-related genes, including ATG16L1 and immunity-related GTPase M (IRGM), two important autophagy-related proteins, were highly related to the pathogenesis of CD (Tysk et al., 1988; Hampe et al., 2007). Here, IRGM is linked to Cowden disease.