Inclusion Criteria:  Patients with an established diagnosis of ulcerative colitis based on clinical symptoms, endoscopic features and histopathologic features Patients who are going to receive vedolizumab, ustekinumab, or tofacitinib treatment  Exclusion Criteria:  Not Korean ethnicity by family history Inflammatory Bowel Disease Unclassified Patients who already received colectomy due to ulcerative colitis