| Phenotype details |
onset 18m-developmental delay; unremarkable neonatal course; mild/moderate intellectual disability, severe developmental delay; increased muscle tone; ataxia; no impaired suckling/swallowing; no epilepsy; mild nystagmus, optic atrophy, no visual impairment; MRI-brain 1y6m-cerebral atrophy, 4y-cerebellar atrophy; max. serum lactate 2.9 mmol/l, lactic acidosis (HP:0003128); encephalopathy (HP:0001298) |