The most common single-gene mutations in ASD with ID are associated with Fragile X syndrome (FXS; FMRI), Tuberous Sclerosis (TSC1, TSC2), Angelman Syndrome (UBE3A), Rett Syndrome (MECP2), and Phlean-McDermid syndrome (SHANK3). Here, TSC1 is linked to fragile X syndrome.