title: Two novel isovaleryl-CoA dehydrogenase gene mutations in a Chinese infant.
abstract: Isovaleric acidemia (IVA) is a rare inherited metabolic disease caused by a deficiency in isovaleryl-CoA dehydrogenase (IVD). Newborn screening with tandem mass spectrometry leads to early identification of individuals with risk of IVA. The family specific mutations are useful for prenatal diagnosis. Molecular genetic analysis helps to further confirm the clinical diagnosis of IVA. We describe here the clinical and metabolic features of a Chinese infant with early onset IVA. Sequence analysis of the IVD gene identifies compound heterozygous mutations in this patient, c.39G>A (p.W13X) nonsense mutation and c.597C>G (p.I199 M) missense mutation, both of which are previously unreported. Structural analyses suggest that the p.I199 M missense mutation may destabilize the IVD monomer structure and affect the interaction between IVD and flavin adenine dinucleotide. Both the clinical and genetic features of this patient help to further expand our knowledge of IVA.
authors.affiliation: Department of Clinical Nutrition, Xin Hua Hospital, Shanghai Jiao Tong University School of Medicine, 1665 Kongjiang Road, Shanghai 200092, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Bei
authors.forename: Jian-Hua
authors.initials: JH
authors.lastname: Sun
authors.forename: Yong-Guo
authors.initials: YG
authors.lastname: Yu
authors.forename: Jia
authors.initials: J
authors.lastname: Jia
authors.forename: Zhao-Jing
authors.initials: ZJ
authors.lastname: Zheng
authors.forename: Qi-Hua
authors.initials: QH
authors.lastname: Fu
authors.forename: Wei
authors.initials: W
authors.lastname: Cai
mesh_terms: D000592:Amino Acid Metabolism, Inborn Errors / Q000235:genetics* / Q000378:metabolism; D000595:Amino Acid Sequence; D044466:Asian People / Q000235:genetics; D004795:Enzyme Stability; D005260:Female; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism*; D005415:Flavins / Q000378:metabolism; D006579:Heterozygote; D006801:Humans; D007231:Infant, Newborn; D050769:Isovaleryl-CoA Dehydrogenase / Q000172:deficiency / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D020125:Mutation, Missense; D025941:Protein Interaction Mapping
chemical_list: D005415:Flavins; D005182:Flavin-Adenine Dinucleotide; C008173:isoalloxazine; D050769:Isovaleryl-CoA Dehydrogenase