Our results suggest that in this case series of PEXG, a particular type of glaucoma in which there is upregulation of MMP-2 production with a marked increase in the relative inhibitors [22,23], the changes in the TIMP-2/MMP-2 ratio that can be obtained with laser trabeculoplasty are insignificant and thus are unable to decrease intraocular pressure. The gene discussed is MMP2; the disease is glaucoma.