Assessment of Brain-derived Neurotrophic Factor (BDNF) Gene Polymorphism in a Patients with Cohort of Egyptian Primary Open-Angle Glaucoma (POAG)

Abstract

This study was conducted to assess the role of the brain-derived neurotrophic factor (BDNF) gene poly- morphism (rs2030324) in primary open-angle glaucoma (POAG) patients. Primary open-angle glaucoma (POAG), the most common kind, is the second greatest cause of blindness in the world. A member of the neurotrophin family, brain-derived neurotrophic factor (BDNF) is produced by retinal ganglion cells (RGCs). With optic nerve dystrophy, the axonal transport of neurotrophins is disrupted, depriving the RGCs of BDNF support and causing glaucomatous retinal cell loss.

This case-control study was conducted on 50 POAG patients (mean age 55 ± 10) and 50 healthy control subjects (mean age 40 ± 11). Both groups underwent full ophthalmological examination. Genomic DNA was extracted followed by BDNF rs2030324 genotyping by real time PCR.

Correlation coefficient analysis showed significant positive correlation between age and right and left cup to disc ratio (r = 0.448, p = 0.001; r = 0.283, p = 0.004 respectively) and significant negative correlation between intraocular pressure and right and left VA (r = - 0.212, p = 0.034; r = - 0.258, p = 0.009 respectively). No significant difference between the 2 groups was found as regards genotype or alleles frequency distribution (p = 0.722).

This study did not succeed to illustrate the role of BDNF gene polymorphism (SNP rs2030324) as a risk factor for POAG occurrence. The mechanism of glaucoma development according to the BDNF polymorphism remains unclear. The study recommend further studying of BDNF gene polymorphism SNP rs2030324 on larger sample size and using DNA sequencing techniques for detec- tion of different BDNF gene polymorphisms and other genes involved in the neurodegeneration mechanism for better understanding of the molecular basis of POAG and to find early diagnostic markers of POAG development.