An amino acid metabolic disorder characterized by inability to process isoleucine and ketones, has_symptom recurrent ketoacidotic attacks in infancy marked by vomitting, lethargy, dehydration, and seizures, and has_material_basis_in mutation in the ACAT1 gene of chromosome 11q22.3 responsible for producing the ACAT1 enzyme in mitochondria, which processes isoleucine and ketones.