Previous studies have found elevated levels of IL-9, IL-12, IFN-α, IFN-γ, monokine induced by interferon–gamma (MIG or CXCL9), and IL-10 in POAG patients; these cytokines play a role in Th1-mediated proinflammatory response and leukocyte activation [10]. The gene discussed is CXCL9; the disease is open-angle glaucoma.