Genetic Variation of Superoxide Dismutases in Patients with Primary Open-angle Glaucoma

Abstract

Purpose: Oxidative stress has been described as an underlying pathogenetic mechanism in retinal ganglion cell apoptosis, which is a hallmark of primary open-angle glaucoma (POAG). Superoxide dismutases (SODs) are enzymes involved in the protection against oxidative stress by detoxification of superoxide. In this study, we investigated a number of disease-associated single nucleotide polymorphisms (SNPs) in the copper-zinc-containing SOD1 and SOD3, and in the manganese superoxide dismutase SOD2, in POAG patients.

Methods: The study included 239 patients with POAG and 185 controls, all of Estonian origin, recruited at two ophthalmic clinics in Tartu, Estonia. Eleven SNPs, either functional, disease-associated or tag SNPs in SOD1, SOD2 and SOD3 were genotyped using TaqMan Allelic Discrimination. Haplotype analysis was performed on the SNPs in SOD2.

Results: Using binary logistic regression in an additive model, the rs2842980 SNP in SOD2 was significantly associated with POAG diagnosis (p = 0.03) at a univariate level. None of the studied SNPs showed an association with risk of POAG in a multivariate analysis, including age and current smoking as covariates. Analysis of SOD2 haplotypes did not show any association with risk of POAG.

Conclusions: If oxidative stress is an important mechanism in POAG-related retinal ganglion cell death, genetic variations in SOD1, SOD2 and SOD3 are not major contributors in the pathogenesis.

• Oxidative stress
• primary open-angle glaucoma
• single nucleotide polymorphisms
• SOD genes