Technological innovations such as Genome-wide association study (GWAS), whole exome sequencing (WES), and fine-mapping have dramatically facilitated genetic research in IBD, identifying more than 240 susceptibility loci of IBD, including TNF superfamily member 15 (TNFSF15), interleukin 23 receptor (IL23R), autophagy related 16 like 1 (ATG16L1), immunity related GTPase M (IRGM), PR/SET domain 1 (PRDM1), and nuclear dot protein 52 kDa (NDP52, also known as CALCOCO2) (Ellinghaus et al., 2013; Liu et al., 2015; de Lange et al., 2017). Here, CALCOCO2 is linked to inflammatory bowel disease.