Significant Association and Increased Risk of Primary Open Angle Glaucoma with TGFB2 Rs991967 Gene Polymorphism in North Eastern Iranian Patients

Glaucoma is one of the main causes of irreversible blindness. The most common type of glaucoma is primary open angle glaucoma (POAG). TGF-β2, the main TGF-β isoform in the eye, is critical for extracellular matrix production and angiogenesis. Genetic studies have shown that TGF-β2 gene (TGFB2) polymorphisms affect its expression in the eye. The aim of this study was to investigate the presence of the TGFB2 rs991967 polymorphism in POAG, and the effect of this polymorphism on clinical characteristics in POAG patients. This case-control study was conducted on 112 control participants and 112 POAG patients referred to Khatam-Al-Anbia Eye Hospital, Mashhad, Iran. The TGFB2 rs991967 polymorphism was genotyped by the PCR-restriction fragment length polymorphism (PCR-RFLP) method. The genotyping results and clinical findings were analyzed using SPSS version 16. The most common genotype was AA, observed in 54.5% of the patients (P < 0.0001, OR 12.2, CI 95% for OR: 5.25 to 28.31). Moreover, the highest and lowest frequencies of the mutant A allele were seen in the patient and control groups with percentages of 73 and 40%, respectively. This difference was significant (P < 0.0001, OR: 3.9, CI 95% for OR: 2.6 to 5.9). No significant association was seen between the frequencies of the TGFB2 rs991967 polymorphism genotypes and clinical characteristics in POAG patients. The TGFB2 rs991967 polymorphism has a direct and significant association with POAG and significantly increases the risk of developing POAG.