A combined analysis investigating both rare and common gene variants supported the evidence of the role of several genes/loci associated with autism (e.g., NRXN1, ADNP, 22q11 deletion) and revealed new variants in known autism-risk genes such as ADPNP, NRXN1, NINL, MECP2 and identified new compelling candidate genes such as KALRN, PLA2G4A, and RIMS4 [22]. This evidence concerns the gene MECP2 and autism.