title: Missense variants of the alanine:glyoxylate aminotransferase 2 gene are not associated with Japanese schizophrenia patients.
abstract: Alanine:glyoxylate aminotransferase 2 (AGXT2) is the only enzyme that degrades D-3-aminoisobutyrate (D-AIB), which is an intermediate product of thymine, and 30-40% of Japanese lack AGXT2 activity genetically and excrete high amounts of D-AIB in their urine. Recently, AGXT2 is reported to metabolize asymmetric dimethyl arginine (ADMA), a competitive inhibitor of nitric oxide (NO) synthase. Since AGXT2 is expressed in the central nervous system, the loss of AGXT2 activity will be related to the vulnerability for neuropsychiatric disorders related to the NO system. In this study, we recruited 85 Japanese subjects to discover loss variants of the AGXT2 gene with the amount of D-AIB excretion in their urine. From the statistical relevance between them, we found three missense polymorphisms (rs37370, rs37369, and rs180749) independently related to AGXT2 activity (P<0.0001). Then, we performed a case-control association analysis of its missense polymorphisms with 1136 schizophrenia and 1908 control subjects because the NO system may be involved in the vulnerability of schizophrenia processes. We could not find any associations of three functional SNPs with schizophrenia pathogenesis in the analyses of either genotypic or allelic models. We concluded that the AGXT2 gene is not associated with schizophrenia in Japanese subjects.
authors.affiliation: Department of Neuropsychiatry, Molecule Function, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan. Electronic address: whisperoftheheart2@yahoo.co.jp.
authors.forename: Yuta
authors.initials: Y
authors.lastname: Yoshino
authors.affiliation: Department of Neuropsychiatry, Molecule Function, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Abe
authors.affiliation: Department of Psychiatry, Course of Integrated Brain Sciences, Medical Informatics, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-8-15 Kuramoto-cho, Tokushima 770-8503, Japan.
authors.forename: Shusuke
authors.initials: S
authors.lastname: Numata
authors.affiliation: Department of Neuropsychiatry, Molecule Function, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Ochi
authors.affiliation: Department of Neuropsychiatry, Molecule Function, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Mori
authors.affiliation: Department of Neuropsychiatry, Molecule Function, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ishimaru
authors.affiliation: Department of Psychiatry, Course of Integrated Brain Sciences, Medical Informatics, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-8-15 Kuramoto-cho, Tokushima 770-8503, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Kinoshita
authors.affiliation: Department of Psychiatry, Course of Integrated Brain Sciences, Medical Informatics, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-8-15 Kuramoto-cho, Tokushima 770-8503, Japan.
authors.forename: Hidehiro
authors.initials: H
authors.lastname: Umehara
authors.affiliation: Department of Neuropsychiatry, Molecule Function, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Kiyohiro
authors.initials: K
authors.lastname: Yamazaki
authors.affiliation: Department of Neuropsychiatry, Molecule Function, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Mori
authors.affiliation: Department of Psychiatry, Course of Integrated Brain Sciences, Medical Informatics, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-8-15 Kuramoto-cho, Tokushima 770-8503, Japan.
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Ohmori
authors.affiliation: Department of Neuropsychiatry, Molecule Function, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan.
authors.forename: Shu-ichi
authors.initials: S
authors.lastname: Ueno
mesh_terms: D000328:Adult; D000621:Aminoisobutyric Acids / Q000652:urine; D044466:Asian People; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D005260:Female; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D020125:Mutation, Missense / Q000235:genetics*; D009569:Nitric Oxide; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D012559:Schizophrenia / Q000235:genetics* / Q000652:urine; D013223:Statistics as Topic; D000637:Transaminases / Q000235:genetics*
chemical_list: D000621:Aminoisobutyric Acids; D009569:Nitric Oxide; D000637:Transaminases; C019635:Alanine-glyoxylate transaminase; C033435:3-aminoisobutyric acid
keywords: Alanine:glyoxylate aminotransferase 2; Asymmetric dimethylarginine; D-3-aminoisobutyrate; Nitric oxide; Schizophrenia