Immunochiemical and Molecular Analysis Medium-Chain Acyl CoA Dehydrogenase Deficiency

抄録

Medium-chain acyl CoA dehydrogenase (MCAD) (acyl-CoA: (acceptor) 2, 3-oxidoreductase, EC 1.3.99.3) deficiency in two patients, MV and AH, was examined by use of an anti-MCAD antibody and the cDNA for the enzyme. No MCAD protein was detected by immunoblot analysis in the fibroblast extract from the first patient MV, while it was present, but not catalytically active in the second patient AH. In order to clarify the molecular mechanism of these deficiencies, a cDNA encoding MCAD was isolated from a human placenta cDNA library. The cDNA contained 1, 263 nucleotides of the coding region, 64 nucleotides of the 5′-noncoding region, and 686 nucleotides of the 3′-noncoding region. The level of mRNA for MCAD in the patients was examined by RNA blot analysis with the cDNA as probe, and the results indicate that the patient MV also had the mRNA and that the level of the mRNA in both patients was almost the same as that of the control subject. Thus it seems that the deficiency in the patients is due to a point mutation(s) and that the position of the mutation(s) in the gene of patient MV is different from that of patient AH.