GLI3 and Greig cephalopolysyndactyly syndrome: These observations, together with the diverse phenotypes resulting from molecular defects in GLI3, serve as a classical example of pleiotropy: GLI3 mutations are known to cause different clinical entities: Greig Cephalopolysyndactyly Syndrome (GCPS) (MIM ID #175700), Pallister-Hall Syndrome (MIM ID #146510), Acrocallosal Syndrome (MIM ID #200990), Pre-axial Polydactyly type IV (MIM ID #174700) and Post-axial Polydactyly type A (MIM ID #174200).