Cerebrocostomandibular syndrome (CCMS) is characterized mainly by severe micrognathia, rib defects, and mental retardation. A spectrum of rib gap defects have been reported ranging from a few dorsal rib segments to complete absence of ossification. In about half of the 65 reported cases to date, there is cerebral involvement including mental retardation, microcephaly, and histologic anomalies. Both autosomal dominant and autosomal recessive forms of the disorder have been described (Zeevaert et al., 2009). See CDG2G (611209) for a cerebrocostomandibular-like syndrome.