Quantitative and qualitative defects in development of
the prosencephalic neural crest. Fish-like facial (mouth) appearance. Other
craniofacial anomalies include triangularly shaped face, small nose, partial
absence of tissue (coloboma) from the midportion of nostril walls. Heart,
kidney, and liver anomalies are present, especially in neonates. Other
features include skin and genitalia anomalies, absent eyelids, alopecia
totalis, camptodactyly. Infants and children with AMS show delayed language
development and mental retardation.