PDIA5 and open-angle glaucoma: Single nucleotide polymorphisms (SNPs) in two genes involved in reduction of endoplasmic reticulum (ER) stress, protein disulphide isomerase family A member 5 (PDIA5) and Baculoviral inhibitor of apoptosis repeat-containing 6 (BIRC6), have been recently shown to be significantly associated with POAG [15], [16].