While there is a lack of studies exploring the association between diabetes mellitus and IBD, it has been reported that the use of metformin and dipeptidyl peptidase-4 inhibitors, which are the most frequently prescribed drugs for the management of diabetes mellitus in South Korea (44), could mitigate the risk of IBD in patients with diabetes mellitus (45, 46). The gene discussed is DPP4; the disease is inflammatory bowel disease.