Inheritance: autosomal dominant
Clinical features:
(1) developmental delay or intellectual disability
(2) dysmorphic facial features
(3) markedly delayed or absent speech
(4) hypotonia
(5) joint laxity
(6) strabismus or other ocular abnormalities
(7) hand and foot skeletal abnormalities (short fifth finger, short fourth metacarpal, short fifth metacarpal, thumb abnormalities)
(8) growth retardation
(9) failure to thrive
(10) hearing loss (conductive and/or sensorineural)
(11) genital abnormalities (labial adhesions in females; hypospadias or micropenis in males)
(12) variable congenital diaphragmatic hernia
(13) variable GI malformations (intestinal atresia, imperforate anus)
(14) variable cardiovascular malformations
(15) variable myelomeningocele
(16) variable structural brain abnormalities
(17) recurrent infections
(18) behavioral problems
Dymorphic facial features:
(1) high anterior hairline
(2) hypertelorism with deep-set eyes
(3) triangular-shaped face
(4) epicanthal folds with downslatting palpebral fissures
(5) broad or depressed nasal bridge
(6) small mouth
(7) long, smooth philtrum
(8) full lower lip
