Among the 364 patients with non-variceal upper gastrointestinal bleeding, 49 (13.5%) were classified as Grade I (Hb 10–12 g/dL), 130 (35.7%) as Grade II (Hb 8–10 g/dL), 140 (38.5%) as Grade III (Hb 5–8 g/dL), and 45 (12.4%) as Grade IV (Hb < 5 g/dL). Here, GSTM1 is linked to Gastrointestinal hemorrhage.