EIF2AK3 and open-angle glaucoma: There are several lines of evidence that POAG pathogenesis may be strictly correlated at the molecular level with the Endoplasmic Reticulum (ER) stress conditions and subsequent activation of the protein kinase RNA-like endoplasmic reticulum kinase (PERK)-mediated Unfolded Protein Response (UPR) signaling pathway [16,17,18,19].