title: A mutation on exon 6 of guanidinoacetate methyltransferase (GAMT) gene supports a different function for isoform a and b of GAMT enzyme.
abstract: A new patient affected by Guanidinoacetate methyltransferase (GAMT) deficiency was reported. This 13-year-old girl presented with mental retardation, as main symptom, associated with a typical pattern of biochemical and neurochemical (brain magnetic resonance spectroscopy) alterations. Molecular study detected a L197P transition on exon 6 of the GAMT gene. Since this mutation leaves the isoform B of the GAMT enzyme unaffected, the occurrence of biochemical alterations and disease in this subject testifies against the possibility that isoform b had GAMT activity.
authors.affiliation: Department of Child Neurology and Psychiatry, University of Rome La Sapienza-Via dei Sabelli 108, 00185 Rome, Italy. vincenzo.leuzzi@uniroma1.it
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Leuzzi
authors.forename: Carla
authors.initials: C
authors.lastname: Carducci
authors.forename: Claudia
authors.initials: C
authors.lastname: Carducci
authors.forename: Maria
authors.initials: M
authors.lastname: Matricardi
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Bianchi
authors.forename: Maria Lucia
authors.initials: ML
authors.lastname: Di Sabato
authors.forename: Cristiana
authors.initials: C
authors.lastname: Artiola
authors.forename: Italo
authors.initials: I
authors.lastname: Antonozzi
mesh_terms: D000293:Adolescent; D004252:DNA Mutational Analysis; D005091:Exons; D005260:Female; D005998:Glycine / Q000031:analogs & derivatives / Q000097:blood; D050937:Guanidinoacetate N-Methyltransferase / Q000235:genetics*; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics* / Q000473:pathology; D007527:Isoenzymes / Q000502:physiology*; D008279:Magnetic Resonance Imaging; D009154:Mutation
chemical_list: D007527:Isoenzymes; D050937:Guanidinoacetate N-Methyltransferase; C004946:glycocyamine; D005998:Glycine