In this work, we assessed all studies reporting the level of oxidative and antioxidative markers in aqueous humor or serum samples of glaucoma patients and found that the blood TAS was lower in the OAG group than in the control group, but antioxidant enzymes, including SOD, GPX, and CAT, were increased in the aqueous humors of the OAG group. The gene discussed is CAT; the disease is glaucoma.