Axial hypotonia, Babinski sign, Behavioral abnormality, Brain atrophy, CNS hypomyelination, Cardiomyopathy, Cerebral atrophy, Cerebral cortical atrophy, Cerebral visual impairment, Decreased fetal movement, Decreased liver function, Delayed speech and language development, Developmental regression, Difficulty walking, Downslanted palpebral fissures, Dyskinesia, EEG with multifocal slow activity, Encephalopathy, Epileptic encephalopathy, Failure to thrive, Feeding difficulties, Feeding difficulties in infancy, Frontal cortical atrophy, Gastroesophageal reflux, Generalized hypotonia, Global developmental delay, High forehead, Hyperreflexia, Hypertelorism, Hypodontia, Hypoplasia of the corpus callosum, Hyporeflexia, Hypsarrhythmia, Impulsivity, Intellectual disability, Involuntary movements, Limb hypertonia, Mental deterioration, Microcephaly, Myoclonus, Nystagmus, Open mouth, Optic atrophy, Optic disc pallor, Poor head control, Profound global developmental delay, Prolonged neonatal jaundice, Proptosis, Ptosis, Reduced tendon reflexes, Retinal degeneration, Rigidity, Secondary microcephaly, Seizure, Short chin, Short nose, Short philtrum, Short stature, Sloping forehead, Spasticity, Status epilepticus, Tremor, Unsteady gait, Upslanted palpebral fissure, Wide nasal bridge