Definition:

Familial exudative vitreoretinopathy (FEVR) is inherited retinal disorders with ocular manifestations that are caused by alterations in the Wnt signaling network. FEVR has an abnormal vascularization of the peripheral retina with the formation of retinal folds, retinal detachment, and in many cases the creation of a fibrovascular membrane located behind the lens. Mutations in NDP, FZD4, and LRP5 have been reported to be responsible for ophthalmic diseases including Norrie disease, FEVR, and osteoporosis pseudoglioma syndrome. The proteins encoded by these genes have all been shown to participate in the Wnt/Norrin signaling pathway. Recently, heterozygous mutations in TSPAN12, which is a component of the Norrin-FZD4-LRP5 signaling complex, have been found to be responsible for autosomal dominant FEVR.