In addition to the nucleotide-binding oligomerization domain 2/caspase recruitment domain-containing protein 15 (NOD2/CARD15) [1], [2], various novel susceptibility loci such as the interleukin-23 receptor (IL23R) [3], [4], the ATG16L1 (autophagy-related 16-like 1) gene [5], [6] and variants in the 5p13.1 region [7] have been identified as susceptibility variants in CD patients. The gene discussed is ATG16L1; the disease is Cowden disease.