Mutations in the myocilin gene (MYOC) are the most common known genetic cause of POAG (Stone et al., 1997), and topical ocular 4-PBA was demonstrated to reduce phenotypes of glaucoma in mice with this mutation by reducing myocilin accumulation and ER stress in the TM, in addition to systemic administration of 4-PBA preventing glaucoma in the same mouse model altogether by promoting the secretion of mutant myocilin in AH and decreasing intracellular accumulation of myocilin in the ER to prevent TM cell death (Zode et al., 2011; 2012). This evidence concerns the gene MYOC and open-angle glaucoma.