Furthermore, in the subsequent analyses based on disease type, ethnicity, control design and genotyping methods, a significant protective effect against glaucoma risk was observed for MMP-9 rs17576 G > A in Caucasian populations (GA vs. GG: OR = 0.67, 95%CI = 0.45-1.00, P = 0.05, I2 = 0 (Fig. 2); GA + AA vs. GG: OR = 0.66, 95%CI = 0.45-0.97, P = 0.03, I2 = 0%) (Table 3). This evidence concerns the gene MMP9 and glaucoma.