Zinc concentration corresponding to filling the high-affinity site in PEDF (4 μM) matches the level of elevated zinc in AH of some patients with POAG (2–7 μM), suggesting that this metal is unlikely to bind to PEDF under normal conditions (0.4–0.5 μM Zn2+) but may be captured under pathologic conditions. Here, SERPINF1 is linked to open-angle glaucoma.