title: A linkage study between the GABAA beta2 and GABAA gamma2 subunit genes and major psychoses.
abstract: BACKGROUND
  Alterations of the gamma-aminobutyric acid (GABA) system have been implicated in the pathophysiology of major psychoses.
  
  
  OBJECTIVE
  Restriction fragment length polymorphisms associated with the human gamma-aminobutyric acid type A (GABAA) beta2 and GABAA gamma2 subunit genes on chromosome 5q32-q35 were tested to determine whether they confer susceptibility to major psychoses.
  
  
  METHODS
  Thirty-two schizophrenic families and 25 bipolar families were tested for linkage.
  
  
  RESULTS
  Nonparametric linkage (NPL) analysis performed by GENEHUNTER showed no significant NPL scores for both genes in schizophrenia (GABAA beta2: NPL narrow= -0.450; NPL broad= -0.808; GABAA gamma2: NPL narrow=0.177; NPL broad= -0.051) or bipolar disorder (GABAA beta2: NPL narrow=0.834; NPL broad=0.783; GABAA gamma2: NPL narrow= -0.159; NPL broad=0.070).
  
  
  CONCLUSIONS
  Linkage analysis does not support the hypothesis that variants within the GABAA beta2 and GABAA gamma2 genes are significantly linked to major psychoses in a Portuguese population.
authors.affiliation: Unit of Clinical and Molecular Genetics, National Institute of Legal Medicine, Faculty of Medicine, University of Coimbra, Largo da Se Nova, 3000-213 Coimbra, Portugal. aldachico@yahoo.com
authors.forename: Alda M
authors.initials: AM
authors.lastname: Ambrósio
authors.forename: James L
authors.initials: JL
authors.lastname: Kennedy
authors.forename: Fabio
authors.initials: F
authors.lastname: Macciardi
authors.forename: Nicole
authors.initials: N
authors.lastname: King
authors.forename: Maria H
authors.initials: MH
authors.lastname: Azevedo
authors.forename: Catarina R
authors.initials: CR
authors.lastname: Oliveira
authors.forename: Carlos N
authors.initials: CN
authors.lastname: Pato
mesh_terms: D001714:Bipolar Disorder / Q000235:genetics / Q000378:metabolism; D008040:Genetic Linkage / Q000235:genetics*; D006801:Humans; D007438:Introns / Q000235:genetics; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic / Q000235:genetics; D011159:Population Surveillance / Q000379:methods; D017397:Prefrontal Cortex / Q000378:metabolism; D021122:Protein Subunits / Q000235:genetics* / Q000378:metabolism; D011618:Psychotic Disorders / Q000235:genetics* / Q000378:metabolism; D011963:Receptors, GABA-A / Q000378:metabolism; D018080:Receptors, GABA-B / Q000235:genetics* / Q000378:metabolism; D012559:Schizophrenia / Q000235:genetics / Q000378:metabolism
chemical_list: D021122:Protein Subunits; D011963:Receptors, GABA-A; D018080:Receptors, GABA-B