These studies have identified many driver genes, whose mutations confer selective growth advantage to tumor.11 Some of these driver genes are previously known cancer genes (eg, TP53, ARID1A, and CDH1), while the others are new‐found significantly mutated genes in gastric cancer (eg, MUC6, CTNNA2, GLI3, and RNF43).4, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22 Moreover, the copy number changes and characteristic mutational signatures also play important roles in gastric cancer development.4, 16, 17, 18, 19. Here, ARID1A is linked to gastric cancer.