Molecular genetic studies have identified five genes mutated in individuals with ACHM, eight genes implicated in COD, and 17 genes implicated in CRD (RetNet, see Web Resources).1,7–9 Cone disorders can follow all modes of Mendelian inheritance and manifest as nonsyndromic and syndromic forms.1,2 Cone-disease-associated genes encode proteins that fulfill crucial roles in the cone phototransduction cascade, transport processes toward or through the connecting cilium, cell membrane morphogenesis and maintenance, synaptic transduction, and the retinoid cycle.1,7–9