SIX6 and open-angle glaucoma: In contrast, with the exception of variant rs10483727 in (SIX1/SIX6) gene locus [25], our previous studies to identify genetic polymorphisms associated with Saudi POAG patients in genes including caveolin 1/caveolin 2 (CAV1/CAV2) [26], atonal homolog 7 (ATOH7) [27], (CDKN2B) [28], transmembrane and coiled-coil domain 1(TMCO1) [29], (GAS7) [30] and ZP4 [13, 14], have yielded negative results indicating that the plausible causal genetic defect(s) in POAG cases of Saudi origin may be different than those from European, African and Asian descents, including the Japanese population.