LOXL1 gene analysis in Turkish patients with exfoliation glaucoma

The purpose of this study is to evaluate whole lysyl oxidase like 1 (LOXL1) gene by sequence analysis in Turkish patients with exfoliation glaucoma (XFG). A total of 48 (35 male, 13 female) patients with XFG were enrolled. Besides routine ophthalmological examination, peripapillary retinal nerve fibre layer (RNFL) analysis with optic coherence tomography was performed. Blood samples of 2 ml with EDTA were obtained and sent to Medical Genetics Department, Molecular Genetics Laboratory for LOXL1 polymorphism (PCR and agarose gel imaging) analysis. The role of the detected changes on disease severity was evaluated. No LOXL1 gene mutations in any of the patients were detected. Three types of single-nucleotide polymorphisms (SNPs) including R141L(rs1048661), A320A(rs41435250), and F184F were detected in 17 (35.3 %) patients. When compared, SNP-positive patients had thinner RNFL than SNP-negative patients (64.5 ± 17.6 and 66.1 ± 20.4 µ, respectively), and SNP-positive patients had higher cupping/disc ratio than SNP-negative patients (0.76 ± 0.2 and 0.70 ± 0.3, respectively). However, both values were not statistically significant (p = 0.966 and p = 0.539, respectively). When compared, R141L-positive patients had significantly thinner cornea thickness (516.11 ± 30.3 µ) than R141L-negative patients (556.69 ± 27.2 µ) (p = 0.004). There was not any statistical significant difference in the means of age, gender, BCVA, MD, PSD, IOP, number of hypotensive agents, and percent of glaucoma surgery (p > 0.05). In this study group of Turkish population, no LOXL1 mutations were found. No associations between the defined SNPs (A320A, R141L and F184F) and the severity of the disease were detected.