Perivascular cells around choroidal vessels have also been hypothesized to regulate the stability of choroidal vasculature [6], [14], and are relevant to the formation of choroidal neovascularization (CNV) [15]–[17], the aberrant vascular growth responsible for vision loss in the exudative form of AMD, and also to the resistance of CNV to anti-vascular endothelial growth factor (VEGF) therapies [18], [19]. The gene discussed is VEGFA; the disease is choroidal neovascularization.