Currently, the biomarkers used to screen for GC such as glycoprotein chain antigen 125 (CA125), CA19-9, CA72-4, pepsinogen I/II ratio (PG I/PG II), gastrin-17 (G-17), anti-gastric parietal cell antibodies (APCA), squamous cell carcinoma antigen (SCCA), cytokeratin 19 fragment (CYFRA 21-1), and carcinoembryonic antigen (CEA) are found to be not sensitive and specific enough during the time of diagnosis, as reported by studies (3, 102, 103). This evidence concerns the gene GAST and gastric cancer.