RS1 and X-linked retinoschisis: Mutations in the gene encoding RS1 cause X-linked juvenile retinoschisis that features disorganization of retinal cell layers, disruption of synaptic structures and neurotransmission between photoreceptors and bipolar cells, and progressive photoreceptor degeneration (Weber et al., 2002), since RS1 is critical in stabilizing the synaptic connections during development (Takada et al., 2004; Vijayasarathy et al., 2006, 2008).