To systematically elucidate the function of FTO in diabetes-induced retinal vascular endothelial dysfunction, EC-specific Fto-deficient (EC FtoΔ/Δ) mice were generated, as shown in the schematic illustration in Figure 2A. To validate the successful knockout of Fto, the mouse retinal vessels were immunostained using an anti-FTO antibody, and the results verified the complete knockout of endothelial FTO protein (Figure 2B). The gene discussed is FTO; the disease is diabetes mellitus.