As VEGF‐A can induce ROS in cells through the activation of NADPH oxidase that lead to autophosphorylation of Flk1 and downstream activation of ERK (Abid et al, 2000; Colavitti et al, 2002; Monaghan‐Benson & Burridge, 2009), and as both ERK hyperactivation and oxidative stress are known inducers of cataracts, we assessed markers of oxidative stress in lenses of VEGF‐Ahyper mice. The gene discussed is FMO5; the disease is cataract.