| Main clinical features
|
severe neurologic impairment including intellectual disability, intractable epilepsy, microcephaly, abnormal muscle tone, and sensorineural hearing loss
most affected individuals are nonambulatory, cannot sit unassisted, and have no speech development
microcephaly, developmental delay, intellectual disability, hypotonia, spasticity, seizures, sensorineural hearing loss, cortical visual impairment
abnormal EEG, and brain MRI was often abnormal, showing variable diffuse atrophy, cortical atrophy, thin corpus callosum, and hypomyelination |