1Eur. Psychiatry 2005 Jan 20: 45-9
PMID15642443
TitleAn association study between polymorphisms in five genes in glutamate and GABA pathway and paranoid schizophrenia.
AbstractDysfunctions of glutamatergic and GABAergic neurotransmission are two important hypotheses for the pathogenesis of schizophrenia. Thus, genes in the pathway are candidates for schizophrenia susceptibility. Phosphate-activated glutaminase (GLS), glutamine synthetase (GLUL), glutamic acid decarboxylase (GAD), GABA transaminase (ABAT) and succinic semialdehyde dehydrogenase (ALDH5A1) are five primary enzymes in glutamate and GABA synthetic and degradative pathway. In order to investigate the possible involvement of these genes in the development of paranoid schizophrenia, we genotyped 80 paranoid schizophrenics from northern China and 108 matched controls by polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP) methods or directly sequencing of PCR product. Seven SNPs were found to be polymorphic in the population investigated. No significant differences in the genotype distributions or allele frequencies between patients and controls were found. Therefore, we conclude the polymorphisms studied in the five genes do not play major roles in pathogenesis of paranoid schizophrenia in the population investigated.
SCZ Keywordsschizophrenia, schizophrenics
2Eur. Psychiatry 2005 Jan 20: 45-9
PMID15642443
TitleAn association study between polymorphisms in five genes in glutamate and GABA pathway and paranoid schizophrenia.
AbstractDysfunctions of glutamatergic and GABAergic neurotransmission are two important hypotheses for the pathogenesis of schizophrenia. Thus, genes in the pathway are candidates for schizophrenia susceptibility. Phosphate-activated glutaminase (GLS), glutamine synthetase (GLUL), glutamic acid decarboxylase (GAD), GABA transaminase (ABAT) and succinic semialdehyde dehydrogenase (ALDH5A1) are five primary enzymes in glutamate and GABA synthetic and degradative pathway. In order to investigate the possible involvement of these genes in the development of paranoid schizophrenia, we genotyped 80 paranoid schizophrenics from northern China and 108 matched controls by polymerase chain reaction (PCR) and restriction fragment length polymorphisms (RFLP) methods or directly sequencing of PCR product. Seven SNPs were found to be polymorphic in the population investigated. No significant differences in the genotype distributions or allele frequencies between patients and controls were found. Therefore, we conclude the polymorphisms studied in the five genes do not play major roles in pathogenesis of paranoid schizophrenia in the population investigated.
SCZ Keywordsschizophrenia, schizophrenics
3Pharmacogenet. Genomics 2008 Apr 18: 317-23
PMID18334916
TitlePathway-based association analysis of genome-wide screening data suggest that genes associated with the gamma-aminobutyric acid receptor signaling pathway are involved in neuroleptic-induced, treatment-resistant tardive dyskinesia.
AbstractNeuroleptic-induced tardive dyskinesia (TD) is an involuntary movement disorder that develops in patients who have undergone long-term treatment with antipsychotic medications, and its etiology is unclear. In this study, a genome-wide association screening was done to identify the pathway(s) in which genetic variations influence susceptibility to neuroleptic-induced TD.
Screening with Sentrix Human-1 Genotyping BeadChip (Illumina, San Diego, California, USA) was done for 50 Japanese schizophrenia patients with treatment-resistant TD and 50 Japanese schizophrenia patients without TD. A total of 40 573 single nucleotide polymorphisms that were not in linkage disequilibrium with each other and were located in the exonic and intronic regions of 13 307 genes were analyzed. After gene-based corrections, P values for allelic associations were subjected to canonical pathway-based analyses with Ingenuity Pathway Analysis software (Ingenuity Systems, Inc., Redwood City, California, USA).
Eight genes (ABAT, ALDH9A1, GABRA3, GABRA4, GABRB2, GABRAG3, GPHN, and SLC6A11) contained polymorphisms with gene-based corrected allelic P values of less than 0.05. They were aggregated significantly in 33 genes belonging to the gamma-aminobutyric acid (GABA) receptor signaling pathway (P=0.00007, corrected P=0.01). Associations were replicated in an independent sample of 36 patients with TD and 136 patients without TD for polymorphisms in SLC6A11 (GABA transporter 3) (P=0.0004 in the total sample), GABRB2 (beta-2 subunit of GABA-A receptor) (P=0.00007 in the total sample), and GABRG3 (gamma-3 subunit of GABA-A receptor) (P=0.0006 in the total sample).
The results suggest that the GABA receptor signaling pathway may be involved in genetic susceptibility to treatment-resistant TD, at least in a subgroup of Japanese patients with schizophrenia. The present results suggest that benzodiazepines may be considered as possible treatment option for TD.
SCZ Keywordsschizophrenia, schizophrenics