Vascular endothelial growth factor A genetic polymorphisms and AMD in Tunisians

Abstract

AbstractPurpose To determine whether vascular endothelial growth factor (VEGF) gene polymorphism plays a role in either susceptibility risk for exudative AMD, serum VEGF levels variations and treatment with intravitreal bevacizumab in TunisiansMethods In this case–control study, we included 96 patients with exudative AMD and 207 age‐matched controls treated with intravitreal bevacizumab. Single nucleotide polymorphism (SNP) genotyping was performed using restriction fragment length polymorphism (RFLP) analysis of polymerase chain reaction (PCR) products. The serum VEGF was assayed by ELISA (R&D).Results The frequency of the VEGF ‐2578 A allele was significantly higher in AMD patients than in controls (p=0.005; OR: 2.12[1.23‐3.66]) and was statistically associated to higher serum levels of VEGF (93.30 pg/ml versus 39.75 pg/ml for C allele) (p: 0.021). When examining the effect of this polymorphism on post‐treatment visual acuities (VA), we observed that A variant allele was also statistically more prevalent among patients with better outcome for distance and reading visual acuity after three bevacizumab injections compared to those with loss of 3 or more lines in visual acuity (OR = 2.5, 95% CI [1.13‐5.73], p = 0.02). Furthermore, the mean of VEGF plasma level is significantly higher (170.97 pg/ml) in patients with enhanced VA compared to those with worse outcome for distance and reading visual acuity (45.52pg/ml) (p=0.003).Conclusion In addition to the higher risk for exudative AMD in Tunisian patients with the ‐2578 A VEGF, our results show that this allelic variant also correlates with better visual acuity outcome after treatment with bevacizumab probably through a functional or quantitative variation of plasma levels of this molecule.