From which, 10 somatic variation were detected on chronic gastritis (ATXN3, PLIN4, PDZD2, MUC4, MUC17, DMBT1, DAB1, ZNF208, FLG2 and CRNN), 23 somatic variations were occurred in primary cancer (ATXN3, PLIN4, PDZD2, MUC4, MUC17, DMBT1, DAB1, TUBB6, RP1L1, PRB1, PKLR, JAM2, ITGAD, IREB2, IQUB, HS6ST3, DCTN1, CORO1B, CCDC178, CCDC121, AKAP2, ACAN and ACADL), and 12 somatic variations in metastatic cancer (ATXN3, PLIN4, PDZD2, MUC4, DMBT1, DAB1, CRNN, RP1L1, PRB1, HS6ST3, DCTN1 and ARMC4). The gene discussed is ITGAD; the disease is chronic gastritis.