title: Glutamatergic markers, age, intellectual functioning and psychosis in 22q11 deletion syndrome.
abstract: BACKGROUND
  Patients with 22q11 deletion syndrome (22q11DS) have a high prevalence of intellectual disabilities and psychiatric disorders, including psychosis. Haplo-insufficiency of genes in the deleted region may offer a partial explanation for the increased vulnerability for psychosis and intellectual disability. One gene of particular interest is the gene coding for proline dehydrogenase (PRODH), an enzyme responsible for the conversion of proline into glutamate.
  
  
  OBJECTIVE
  Because abnormalities in glutamatergic signaling are thought to be responsible for cognition and psychosis in the general population, we hypothesized that PRODH haplo-insufficiency may underlie some of the cognitive and psychotic features seen in 22q11DS.
  
  
  METHODS
  In this explorative study, we investigated the relation between plasma proline, glutamate, and glutamine and age, intelligence, and psychosis in 64 adults with 22q11DS.
  
  
  RESULTS
  Hyperprolinemia was found in 31.3% of subjects with 22q11DS. A relation between glutamine, glutamate, proline, and presence of psychosis was not observed. Regression analysis revealed a positive relation between plasma glutamate and age, a positive relation of glutamate with antipsychotic drugs, a relation of glutamine and gender, and a positive relation of glutamine and mood stabilizing drugs, and a negative relation of the ratio glutamine/glutamate and age. The group with relatively lower IQ had higher glutamate levels compared to the group with relatively higher IQ.
  
  
  CONCLUSIONS
  Our results suggest that 22q11DS is accompanied by abnormalities in glutamatergic metabolism. Future longitudinal studies are needed to further investigate the glutamatergic system in 22q11DS and how this affects the development of cognitive problems and psychopathology.
authors.affiliation: Koraalgroup, MFCG, Panheelderweg 3, 6097 AH, Heel, The Netherlands, revers@stanna.koraalgroep.nl.
authors.forename: Laurens J M
authors.initials: LJ
authors.lastname: Evers
authors.forename: Therese A M J
authors.initials: TA
authors.lastname: van Amelsvoort
authors.forename: Jaap A
authors.initials: JA
authors.lastname: Bakker
authors.forename: Mariken
authors.initials: M
authors.lastname: de Koning
authors.forename: Marjan
authors.initials: M
authors.lastname: Drukker
authors.forename: Leopold M G
authors.initials: LM
authors.lastname: Curfs
mesh_terms: D058165:22q11 Deletion Syndrome / Q000097:blood / Q000150:complications / Q000523:psychology*; D000293:Adolescent; D000328:Adult; D000367:Age Factors; D015415:Biomarkers / Q000097:blood; D003071:Cognition; D005260:Female; D018698:Glutamic Acid / Q000097:blood*; D005973:Glutamine / Q000097:blood*; D006801:Humans; D007360:Intelligence; D007361:Intelligence Tests; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011392:Proline / Q000097:blood*; D011618:Psychotic Disorders / Q000097:blood / Q000209:etiology / Q000523:psychology*; D012044:Regression Analysis; D055815:Young Adult
chemical_list: D015415:Biomarkers; D005973:Glutamine; D018698:Glutamic Acid; D011392:Proline