THBS2 showed the highest diagnostic accuracy with an AUC of 0.91, followed by CTNNB1 (AUC = 0.82), E2F3 (AUC = 0.77), and COL4A1 (AUC = 0.75), indicating their utility as potential biomarkers for distinguishing STAD from normal tissue (Fig. 1 F). The gene discussed is COL4A1; the disease is gastric adenocarcinoma.