Clinical findings may include:
(1) mental deficiency
(2) cataracts
(3) muscle wasting
(4) motor disorder (Parkinsonism, tics, stereotypic behaviors, spastic paraparesis)
(5) ataxia
(6) corpus callosum agenesis
(7) deafness
(8) congenital heart disease
(9) premature degenerative joint disease
Facial dysmorphism:
(1) micrognathia or prognathism
(2) cleft palate
(3) anteverted nares
(4) prominent ears
(5) prominent nasal root
(6) ptosis
(7) microophthalmia
Disorder of calcium homeostasis:
(1) calcification of the external ear
(2) cystic changes in the skeleton
(3) calcification of the basal ganglia
(4) elevated serum calcitonin concentration
