Cerebrocostomandibular syndrome (CCMS) is a potentially lethal developmental disorder characterized by mental handicap, palatal defects, micrognathia, and severe costovertebral defects. Presence of dorsal and posterior rib defects in those affected often lead to respiratory complications and in about 40% of cases can result in death before the age 1.
Autosomal dominant inheritance has been described in patients with CCMS. Studies identified heterozygous mutation in SNRPB (small nuclear ribonucleoprotein polypeptides B and B1) gene to be the causative factor among several CCMS patients.