Background: Promotor analysis is not a routine method in DNA diagnostics, despite the fact that the promoter mutations are known to impact gene expression in ways that are functionally evocative.
The most frequent microvascular consequence of diabetes mellitus (DM) is diabetic retinopathy (DR), which can cause blindness by damaging the retina to the point of vision impairment. Vascular endothelial growth factor (VEGF) is a signalling protein subfamily that is produced by a variety of cells and is involved in angiogenesis and vasculogenesis.
One of the outcomes linked to the VEGF gene polymorphisms is an increased risk of DR. The aim of this study was to assess the association between VEGF gene polymorphisms in the promotor region in a small sample of the Egyptian population. Three types of diabetic patients were recruited for this study: those with proliferative diabetic retinopathy (PDR), non-proliferative diabetic retinopathy (NPDR), and diabetics without retinopathy (DWR). Random blood sugar (RBS), glycosylated haemoglobin (HbA1c), and serum levels of VEGF were all examined.
Results: A significant increase in serum levels of RBS and HbA1c in the PDR group was observed compared to both DWR and NPDR. The serum level of VEGF in the PDR group showed a significant increase compared to the DWR group. The genotyping analysis revealed a significant difference in -2578 C/A polymorphism among diabetic groups. The risk factor escalation was considerably higher in the NPDR groups with the mutant heterozygous genotype (CA) than in the PDR groups. In the genotyping analysis, a significant difference was found. A significant rise in the mutant homozygous genotype (CC) was observed when comparing PDR patients to NPDR.
Conclusion: Two polymorphisms in the VEGF gene, -2578 C/A (rs699947) and -460 T/C (rs833061), have been linked to an increased risk of developing DR. Over time, their expression may contribute to this risk.