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Single Nucleotide Polymorphism (SNP) in Schizophrenia and Schizophrenia Spectrum Disorders: a Population Association Analysis With Hong Kong Chinese

This study has been completed.
Chinese University of Hong Kong
Information provided by:
Hospital Authority, Hong Kong Identifier:
First received: November 21, 2007
Last updated: August 20, 2013
Last verified: August 2013

Gamma-aminobutyric acid (GABA) is the principal inhibitory neurotransmitter in the mammalian central nervous system. It is involved in a wide spectrum of physiological functions, from sleep and sedation to convulsions. A defect in neurotransmission involving GABA in schizophrenia was first propsed in early 1970s, based on neuropathologcial evidence, yet there is a lack of molecular genetic evidence.

Recently, we carried out a pilot study on a region of the GABA-A receptor β2 subunit gene on chromosome 5 and found significant association for single nucleotide polymorphisms (SNPs) in the gene sequence with occurrence of schizophrenia. The current proposal aims to validate this important finding and to conduct a thorough scanning of the complete gene sequences of the GABA-A receptor subunit genes in this chromosomal region, including the three major subunits α1, β2 and γ2. We shall collect samples from Hong Kong Chinese subjects for a case-control study using haplotype maps and comparing the SNP haplotype frequencies in the receptor genes, and hence examine whether these genes are in association with schizophrenia, or other schizophrenia-spectrum disorders, including Alzheimer's disease presenting with psychotic symptoms.

Based on the observation that patients suffering from the catatonic subtype of schizophrenia respond particularly well to benzodiazepines, which bind specifically to GABA-A receptors, we shall also perform data analysis in terms of correlating SNP association with schizophrenia subtypes. Association of GABA-A receptor genes with schizophrenia would be a major step forward to determining whether these genes are susceptibility genes for schizophrenia, thereby paving the way to more effective diagnosis and treatment for this debilitating disease.

Condition Intervention
Schizophrenia Procedure: Extraction of 10ml blood sample for extraction of genomic DNA using DNA purification kits

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: Single Nucleotide Polymorphism (SNP) in Schizophrenia and Schizophrenia Spectrum Disorders: a Population Association Analysis With Hong Kong Chinese

Resource links provided by NLM:

Further study details as provided by Hospital Authority, Hong Kong:

Estimated Enrollment: 32
Study Start Date: July 2004
Study Completion Date: June 2006

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All

Inclusion Criteria:

(For patients:)

  • Diagnosis of schizophrenia under DSM-IV guidelines.

Exclusion Criteria:

(For controls:)

  • Subjects who are known to have blood transmitted disease.
  • Past or current alcohol and /or substance abuse.
  • Past or current major medical and neurological conditions.

(For patients:)

  • As for controls, excepr 3. "neurological conditions" does not include schizophrenia.
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Please refer to this study by its identifier: NCT00562926

NTE Cluster under HA
Hong Kong, China
Shatin Hospital
Hong Kong, China
Tai Po Hospital
Hong Kong, China
The Hong Kong University of Science and Technology
Hong Kong, China
Sponsors and Collaborators
Hospital Authority, Hong Kong
Chinese University of Hong Kong
Principal Investigator: Dicky WS Chung, Dr Department of Psychiatry, Tai Po Hospital
  More Information

Additional Information: Identifier: NCT00562926     History of Changes
Other Study ID Numbers: CREC-2004, 247
Study First Received: November 21, 2007
Last Updated: August 20, 2013

Keywords provided by Hospital Authority, Hong Kong:
Schizophrenia spectrum disorder

Additional relevant MeSH terms:
Schizophrenia Spectrum and Other Psychotic Disorders
Mental Disorders processed this record on August 22, 2017