Identification of a Novel Mutation in the MCCC2 Gene of a Korean Patient with 3-Methylcrotonyl-CoA Carboxylase Deficiency.
- Author:
Byung Chul KIM
1
;
Dong Hwan LEE
;
Chang Seok KI
;
Hyung Doo PARK
;
Tae Youn CHOI
;
Jeong Won SHIN
;
Yong Wha LEE
Author Information
- Publication Type:Case Report
- Keywords: 3-Methylcrotonyl-CoA carboxylase; 3-Methylcrotonyl-CoA carboxylase deficiency; MCCC2 mutation
- MeSH: Carnitine; Exons; Glycine; Humans; Infant, Newborn; Leucine; Mass Screening; Reference Values; Sequence Analysis; Tandem Mass Spectrometry; Valerates
- From:Laboratory Medicine Online 2011;1(2):115-119
- CountryRepublic of Korea
- Language:Korean
- Abstract: 3-methylcrotonyl-CoA carboxylase deficiency is an autosomal recessive disorder characterized by a defect in leucine catabolism. We report the case of an 80-day-old patient with 3-methylcrotonyl-CoA carboxylase deficiency who had elevated levels of 3-hydroxyisovalerylcarnitine (45.56 micromol/L; reference range, <0.65 micromol/L), which was detected using tandem mass spectrometry during newborn screening, and elevated levels of 3-hydroxyisovaleric acid (375.75 mmol/mol Cr) and 3-methylcrotonylglycine (502.36 mmol/mol Cr ), which were detected in urine organic acid analysis. We performed direct sequence analysis of all the exons of the MCCC1 and MCCC2 genes. No mutations were detected in the direct sequence analysis of MCCC1. However sequencing of the MCCC2 gene revealed a mutation caused by a heterozygous G to C transversion [c.313G>C (p.Gly105Arg)] at nucleotide position 313 and a mutation caused by a heterozygous A to T transversion [c.1252A>T (p.lle418Phe)] at nucleotide position 1252. Identification of these 2 novel MCCC2 gene mutations in our patient suggested that analysis of the MCCC1 and MCCC2 genes might prove useful in the diagnosis of 3-methylcrotonyl-CoA carboxylase deficiency.
