FMR1 and Intellectual disability: For example, human orthologs to fly genes CASK (CASK), Mnb (DYRK1A), Dlg-1 (DLG1), Cdc42 (CDC42), Fmr1 (FMR1, FXR1/2), trio (TRIO), Nedd4 (NEDD4L/NEDD4) and CamKII (CAMK2A/B/D) have been linked to intellectual disability.