On the other hand, ER stress and UPR signaling are known to be related to the onset or progression of many ocular diseases, such as retinitis pigmentosa caused by mutated rhodopsin [44], primary open angle glaucoma [45], diabetic retinopathy [46], [47], and age-related macular degeneration [48]. The gene discussed is RHO; the disease is open-angle glaucoma.