Congenital malformation characterized by MICROGNATHIA or RETROGNATHIA; GLOSSOPTOSIS and CLEFT PALATE. The mandibular abnormalities often result in difficulties in sucking and swallowing. The syndrome may be isolated or associated with other syndromes (e.g., ANDERSEN SYNDROME; CAMPOMELIC DYSPLASIA). Developmental mis-expression of SOX9 TRANSCRIPTION FACTOR gene on chromosome 17q and its surrounding region is associated with the syndrome.