Mitochondrial DNA polymerase ? deficiency and mtDNA depletion in a child with Alpers' syndrome

Deficiency of mitochondrial DNA polymerase γ activity was found in a patient with mtDNA depletion and Alpers' syndrome. Metabolic evaluation revealed fasting hypoglycemia, dicarboxylic aciduria, and reduced activity of the electron transport chain in skeletal muscle. The patient died in early childhood of fulminant hepatic failure, refractory epilepsy, lactic acidemia, and coma. mtDNA content was 30% of normal in skeletal muscle and 25% in the liver. The activity of mtDNA polymerase γ was undetectable. Ann Neurol 1999;45:54–58