Based on the partially inactivating LRP5 C1351G mutation found in patients with familial exudative vitreoretinopathy (FEVR) [40], Chen et al. recently substituted glycine at the corresponding conserved cysteine residue in the LRP6-LDLRR, which resulted in reduced Wnt signaling activity [41]. The gene discussed is LRP5; the disease is Familial exudative vitreoretinopathy.