A linkage study between the GABAA β2 and GABAA γ2 subunit genes and major psychoses

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.
CNS spectrums (Impact Factor: 2.71). 02/2005; 10(1):57-61.
Source: PubMed


Alterations of the gamma-aminobutyric acid (GABA) system have been implicated in the pathophysiology of major psychoses.
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.
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).
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.

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    • "Several new candidate genes have recently been identified, involving signal transduction cascades, intracellular signaling, or neuronal networks . These genes include TPH2, HTR3B [145], ADRA2C [146], PIK3C3 [147], GABA A Beta2, GABA A Gamma2 [148], PCDH11Y [149], and GSK3Beta [150] [151]. Most of these genes have shown negative results, but positive associations were reported in HTR3B and PIK3C3. "
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