According to DNA methylation profiles of gastric cancer cells and normal gastric cells from TCGA, the methylation changes of GZMB (p-value < 0.18), ARHGDIB (p-value < 0.18), PSME1 (p-value < 0.26), RUNX1 (p-value < 0.36), RBM5 (p-value < 0.39), POLG (p-value < 0.84), and VAMP5 (p-value < 0.86) were found by the IGECN. This evidence concerns the gene POLG and gastric cancer.