Silent and symptomatic primary carnitine deficiency within the same family due toidentical mutations in the organic cation/carnitine transporter OCTN2

A family of Turkish origin with primary systemic carnitine deficiency in the father and his two sons is described. In all three individuals, the same homozygous mutation in the OCTN2 gene (R471H) was present and carnitine uptake in fibroblasts was deficient. Whereas one boy became symptomatic with a Reye-syndrome-like picture of hepatopathy and encephalopathy in infancy, the other affected family members remained asymptomatic up to their current ages of 28 and 5 years, respectively.