Figure 1. Differences of means for the parameter initial IOP of the right eye for the combined genotypes of GSTM1 and GSTT1. The mean of initial IOP to the right eye was significantly higher in the POAG patients carrying the GSTM1-/GSTT1+ genotype combination compared to those with the GSTM1+/GSTT1+ combination. *CI: Confidence Interval.