Association of tumour necrosis factor-alpha -308 G/A polymorphism with primary open-angle glaucoma

Background:  Tumour necrosis factor-alpha (TNF-α) is an important proinflammatory cytokine driving axonal degeneration and retinal ganglion cell apoptosis in glaucoma. The aim of the study was to evaluate the association of TNF-α -308 G/A and -238 G/A polymorphisms with primary open-angle glaucoma (POAG). Design:  A prospective, case–control study, university hospital setting. Participants:  Eighty-six POAG patients and 193 healthy unrelated controls. Methods:  TNF-α polymorphisms were screened by using direct gene sequencing. Main Outcome Measures:  Frequency of TNF-α -308 G/A and TNF-α -238 G/A promoter polymorphisms in glaucoma and healthy subjects. Results:  The frequencies of TNF-α -308 GA genotype and ‘A’ allele were higher in patients with POAG (22.1% and 12.2%, respectively) in comparison with the control group (10.9% and 6%, respectively) (P = 0.046 and 0.02, respectively), with odds ratios of 2.45 (P = 0.01, 95% CI = 1.23–4.87) and 2.19 (P = 0.013, 95% CI = 1.18–4.08), respectively. Genotype distribution of the TNF-α -238 variants did not yield a statistically significant difference between the two groups (P = 0.87). Conclusion:  TNF-α -308 G/A polymorphism seems to be associated with POAG in Turkish population. However, population-based studies with large number of subjects and long-term follow-up are needed to verify the association of TNF-α -308 G/A polymorphism with glaucoma susceptibility.