Facial abnormalities include midface hypoplasia
with broad and flattened nose, large, inverted, W-shaped mouth, and
malformed ears. Telecanthus, epicanthus, lateral displacement of the
lacrimal puncta, and lacrimal excretory obstruction are characteristic
findings. Because of the weakness of the facial muscles, patients have a
mask-like appearance. Malformations of the extremities can include
camptodactyly, clinodactyly, interdigital webbing, and joint hyperlaxity.
Neurological signs comprise torsion dystonia, increased deep tendon
reflexes, poor coordination, positive Babinski sign, hearing impairment, and
developmental delay.