Excluding effects of hypoxia and NO, POAG is characterized by optic nerve death, known as mediated by apoptosis.19,20 VEGF may also alter apoptotic conditions in optic axons through autocrine and paracrine mechanisms, yielding further evidence of a connection between POAG and VEGF, but we do not claim VEGF as direct cause. Here, VEGFA is linked to open-angle glaucoma.