Molecular analysis in Spanish patients with muscle carnitine palmitoyltransferase deficiency

The most common mutation in muscle carnitine palmitoyl-transferase II (CPT II) deficiency is a missense mutation that replaces a leucine for a serine residue at amino acid position 113 of the CPT II protein (S113L). We perfor med molecular analysis in a group of 14 Spanish patients with CPT II defici ency from ten unrelated families. The S113L mutation was observed in 8 of t he 14 patients studied. Seven patients were homozygous for the mutation, 1 patient was heterozygous, and 6 patients did not carry the mutation on eith er allele. Seven healthy relatives belonging to three different families ca rried the mutation on one allele. One patient carried the missense mutation that replaces a tyrosine for a serine at amino acid position 628 on one al lele. Our data indicate that the S113L is also the most common mutation in Spanish patients with CPT II deficiency in muscle, and that further pathoge nic mutations remain to be identified. (C) 1999 John Wiley & Sons, Inc.