Overall, presence of CagA was associated with an increased risk of developing gastric cancer than gastritis (OR 2.53, 95%CI = 1.15 to 5.53, 613 participants, 7 studies, I2: 78%) (Fig 4), but a comparable risk for both gastric cancer and peptic ulcer disease (OR 0.44, 95%CI = 0.08 to 2.34, 404 participants, 6 studies, I2: 67%) (Fig 5). This evidence concerns the gene S100A8 and gastritis.