Of the seven OPTN mutations that have been identified in patients with adult-onset POAG, one is located in exon 4 (E50K) [13,21], one is located in exon 5 (E103D) [14], two are located in exon 6 (c.691_692insAG and V148V) [13,14,22], one is located in exon 14 (H486R) [14], one is located in exon 16 (R545Q) [13,22], and one is located in intron 13 (IVS 13+21C>G) [14]. Here, OPTN is linked to open-angle glaucoma.