Abstract
Objectives: :
To assess whether genetic polymorphisms of OPA1, the gene responsible for autosomal dominant optic atrophy, are associated with open angle glaucoma (OAG) in the Japanese population.
Methods: :
Genomic DNA was examined in a cohort of 194 Japanese patients with normal tension glaucoma (NTG), 191 patients with primary open angle glaucoma (POAG), and 185 control subjects. The average age was 63.6 ± 13.3 years (mean ± SD) for the NTG patients, 62.3 ± 15.1 years for the POAG patients, and 65.3 ± 11.5 years for the control subjects. The presence or absence of OAG in patients and controls was based on clinical examination and/or ophthalmic records. The OPA1 intervening sequence (IVS) 8+4C/T and IVS 8+32T/C genotypes were determined using PyrosequencingTM analysis, and compared between OAG patients and control subjects.
Results: :
There was a significant difference in the IVS 8+32T/C genotype frequencies between the NTG and control groups (P = 0.0074 Chi–square test), and the frequency of the C allele was significantly higher in the NTG patients compared to the control subjects (19.3% vs. 11.6%, P = 0.0036 Fisher exact test). Adjusted for age, gender, refractive error, and maximum intraocular pressure, an appropriate twofold increased risk of NTG (P = 0.0039, odds ratio [OR] 2.27, 95% confidence interval [CI] 1.30 to 3.97) was found with the C allele in the IVS 8+32T/C polymorphism. However, there were no significant differences in these OPA1 genotype frequencies between the POAG and control groups.
Conclusions: :
The OPA1 gene polymorphism is associated with NTG and may be a maker for NTG in the Japanese population. Further studies in the other ethnic populations should be performed to elucidate the relationship between the OPA1 gene and OAG.
Keywords: candidate gene analysis • genetics