Vascular endothelial growth factor (VEGF) is a pro-angiogenic growth factor (cytokine) which contributes significantly to the pathologic neovascularization in ischemic ocular diseases such as diabetic retinopathy, persistent hyperplastic vitreous syndrome, retinopathy of prematurity and choroidal neovascularization. This evidence concerns the gene VEGFA and diabetic retinopathy.