Lack of association between polymorphism rs540782 and primary open angle glaucoma in Saudi patients

Altaf A. Kondkar, Nikhil B. Edward, Hatem Kalantan, Abdullah S. Al-Kharashi, Saleh Altuwaijri, Gamal Mohamed, Tahira Sultan, Taif A. Azad, Khaled K. Abu-Amero

To investigate whether polymorphism rs540782 on chromsome 1, in close proximity to the Zona Pellucida Glycoprotein 4 (ZP4) gene, is a risk factor for primary open angle glaucoma (POAG). The study genotyped 92 unrelated POAG cases and 95 control subjects from Saudi Arabia using Taq-Man® assay. The genotype frequency distribution did not deviate significantly from the Hardy-Weinberg equilibrium (p > 0.05). Overall, both the genotype and allele frequencies were not significantly different between cases and controls. The minor 'C' allele frequency was 49.4%, which was comparable to the Japanese population and higher than the Indian and Afro-Caribbean populations. Similarly, no significant association was found between genotypes and systemic diseases and health awareness/behavior domain variables. Importantly, glaucoma specific indices, such as intraocular pressure, cup/disc ratio and number of anti-glaucoma medication, also showed no statistically significant effect of genotypes within POAG cases. Polymorphism rs540782 is not a risk factor for POAG in the Saudi cohort.