FZD4 and exudative vitreoretinopathy: Mutations in six of the nine genes (FZD4, TSPAN12, NDP, LRP5, CTNNB1, and CTNNA1), which are related to the Norrin/Wnt signaling pathway and play essential roles in retinal development and angiogenesis [13], can explain 50% of FEVR cases [14].