FMR1 and fragile X syndrome: Our finding that visual processing abnormalities were recovered by the restoration of Fmr1 expression in both newborn (P0) and juvenile (P35) V1 neurons in Fmr1KO mice has important clinical implications and could lead to improved FXS therapies; for example, gene therapy could be a rapid and post-diagnostic therapy for FXS patients, especially as drugs developed to treat FXS have yet to be successful (Michalon et al., 2012; Dolan et al., 2013; Pop et al., 2014; Sun et al., 2016).