Identification of two novel mutations of the carnitine/acylcarnitine translocase (CACT) gene in a patient with CACT deficiency.

Carnitine/acylcarnitine translocase (CACT) transports acylcarnitines into mitochondria in exchange for free carnitine, and is therefore an essential component within the fatty acid beta-oxidation pathway. CACT deficiency is an autosomal recessive disease caused by a mutation of the CACT gene. We have identified two novel mutations of the CACT gene in a patient with CACT deficiency. The first, a deletion mutation (146 del T), leads to premature termination and results in a very immature CACT protein. The second, a splicing mutation (261-10T > G), results in either skipping of exons 3 and 4, or of exon 3 alone, and leads to truncation of the protein. Each of these mutations is hypothesized to destroy the function of the CACT protein. We propose that each of these mutations of the CACT gene play a causative role in the disease.