Most patients have a normal mental development but some are mildly retarded.
Macrocephaly, enlarged supraorbital ridges, basilar invagination, squamous protuberance of occipital bone, bathrocephaly, dolichocephaly, wide cranial sutures, wormian bones, depression of anterior fontanels, dysgenesis or genesis of frontal sinuses, enlarged and J-shaped sella turcica, position of mandibular condyles anterior to glenoid fossae, resorption of condylar heads or mandibular rami, absent mandibular chin button, midfacial hypoplasia, and mandibular micrognathia. Cataract, nystagmus, exophthalmos, hypertelorism, epicanthal folds, abducent palsy, disk pallor, optic atrophy, synophrys, and thick and coarse eyebrows. Compression and osteoporosis of ribs. Umbilical and inguinal hernia. Joint laxity, genu valgum, curving of tibiae and fibulae, fractures, and hip and joint dislocations.