title: Late-onset nonketotic hyperglycinemia caused by a novel homozygous missense mutation in the GLDC gene.
abstract: Nonketotic hyperglycinemia (NKH) is an inborn error of the glycine metabolism. A 9-year-old boy with learning disability and intermittent choreoathetosis during febrile illnesses had elevated plasma glycine level and CSF/plasma glycine ratio (0.044) and a novel homozygous missense mutation (c.605C>T; p.Ala202Val) in the GLDC gene, confirming the diagnosis of NKH. This is the first report of late-onset NKH with a confirmed underlying genetic defect. NKH should be in the differential diagnosis of intermittent choreoathetosis.
authors.affiliation: Division of Biochemical Diseases, Department of Pediatrics, University of British Columbia, Canada.
authors.forename: Catherine
authors.initials: C
authors.lastname: Brunel-Guitton
authors.forename: Brett
authors.initials: B
authors.lastname: Casey
authors.forename: Marion
authors.initials: M
authors.lastname: Coulter-Mackie
authors.forename: Hilary
authors.initials: H
authors.lastname: Vallance
authors.forename: Deborah
authors.initials: D
authors.lastname: Hewes
authors.forename: Sylvia
authors.initials: S
authors.lastname: Stockler-Ipsiroglu
authors.forename: Saadet
authors.initials: S
authors.lastname: Mercimek-Mahmutoglu
mesh_terms: D001483:Base Sequence; D002648:Child; D003915:Dextromethorphan / Q000627:therapeutic use; D018691:Excitatory Amino Acid Antagonists / Q000627:therapeutic use; D005998:Glycine / Q000097:blood / Q000134:cerebrospinal fluid; D050841:Glycine Dehydrogenase (Decarboxylating) / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D020158:Hyperglycinemia, Nonketotic / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics*; D008297:Male; D020125:Mutation, Missense / Q000235:genetics*; D016896:Treatment Outcome
chemical_list: D018691:Excitatory Amino Acid Antagonists; D003915:Dextromethorphan; D050841:Glycine Dehydrogenase (Decarboxylating); D005998:Glycine