RESUMO
Purpose: The aim of this study was to evaluate the frequency of single nucleotide polymorphisms (SNP) of estrogen receptor genes (ESR1: rs12154178, rs1884054 and ESR2: rs1268656, rs7159462) and to assess their possible influence on the clinical phenotype of primary open angle glaucoma (POAG). Methods: The study included 235 patients with POAG (143 patients with normal-tension glaucoma [NTG] and 92 patients with high-tension glaucoma [HTG]), and 165 healthy controls. DNA was isolated from peripheral blood, and SNP genotyping was performed using the Real-Time Polymerase Chain Reaction method to analyze the frequency of selected polymorphic variants of estrogen receptor genes. The clinical phenotype (best-corrected visual acuity, intraocular pressure [IOP], mean deviation [MD], cup to disc ratio, disc hemorrhages, notches, peripapillary atrophy, cold extremities) of participants were examined for association with the polymorphisms. Results: A similar frequency of the polymorphic variants of the studied genes was observed in patients with NTG, HTG and control group. Initial intraocular pressure was the lowest in NTG patients with GG variant of rs1268656 (p = 0.044). The lowest maximal IOP in HTG patients was observed in CC variant of rs12154178 (p = 0.039). Patients with HTG and CC variant of ESR1 polymorphism rs1884054 had the best visual acuity (p = 0.009), similar tendency was also observed in the NTG group. This polymorphic variant of ESR1 gene in HTG was also related to earlier damage in visual field assessed according to MD values and higher percentage of notches. For rs12154178, homozygotic variant CC was related to earlier glaucoma damage according to MD in HTG patients (p = 0.006). For polymorphism rs12154178, disc hemorrhages were found only for those with the AC variant. Cold extremities were most frequent in NTG patients with TT variant of rs1268656 comparing to other variants (p = 0.021). Notches on optic disc were less frequent in patients with CC variant of rs12154178 of ERS-1 gene (p = 0.022). Conclusions: The studied polymorphic variants of ESR1 and ESR2 genes may have an influence on the clinical phenotype of patients with POAG.
