title: Kynurenine 3-monooxygenase polymorphisms: relevance for kynurenic acid synthesis in patients with  schizophrenia and healthy controls.
abstract: BACKGROUND
  Patients with schizophrenia show increased brain and cerebrospinal fluid (CSF) concentrations of the endogenous N-methyl-D-aspartate receptor antagonist kynurenic acid (KYNA). This compound is an end-metabolite of the kynurenine pathway, and its formation indirectly depends on the activity of kynurenine 3-monooxygenase (KMO), the enzyme converting kynurenine to 3-hydroxykynurenine.
  
  
  METHODS
  We analyzed the association between KMO gene polymorphisms and CSF concentrations of KYNA in patients with schizophrenia and healthy controls. Fifteen single nucleotide polymorphisms (SNPs) were selected covering KMO and were analyzed in UNPHASED.
  
  
  RESULTS
  We included 17 patients with schizophrenia and 33 controls in our study. We found an association between a KMO SNP (rs1053230), encoding an amino acid change of potential importance for substrate interaction, and CSF concentrations of KYNA.
  
  
  CONCLUSIONS
  Given the limited sample size, the results are tentative until replication.
  
  
  CONCLUSIONS
  Our results suggest that the nonsynonymous KMO SNP rs1053230 influences CSF concentrations of KYNA.
authors.affiliation: Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Holtze
authors.forename: Peter
authors.initials: P
authors.lastname: Saetre
authors.forename: Göran
authors.initials: G
authors.lastname: Engberg
authors.forename: Lilly
authors.initials: L
authors.lastname: Schwieler
authors.forename: Thomas
authors.initials: T
authors.lastname: Werge
authors.forename: Ole A
authors.initials: OA
authors.lastname: Andreassen
authors.forename: Håkan
authors.initials: H
authors.lastname: Hall
authors.forename: Lars
authors.initials: L
authors.lastname: Terenius
authors.forename: Ingrid
authors.initials: I
authors.lastname: Agartz
authors.forename: Erik G
authors.initials: EG
authors.lastname: Jönsson
authors.forename: Martin
authors.initials: M
authors.lastname: Schalling
authors.forename: Sophie
authors.initials: S
authors.lastname: Erhardt
mesh_terms: D000328:Adult; D000483:Alleles; D001921:Brain / Q000378:metabolism; D056726:Genetic Association Studies; D005838:Genotype; D006801:Humans; D007736:Kynurenic Acid / Q000378:metabolism*; D050601:Kynurenine 3-Monooxygenase / Q000235:genetics* / Q000378:metabolism; D020641:Polymorphism, Single Nucleotide; D012559:Schizophrenia / Q000235:genetics* / Q000378:metabolism
chemical_list: D050601:Kynurenine 3-Monooxygenase; D007736:Kynurenic Acid