No association between the sigma receptor type 1 gene and schizophrenia: results of analysis and meta-analysis of case-control studies

Naohiko Uchida¹^,2 , Hiroshi Ujike¹ , Kenji Nakata¹ , Manabu Takaki¹ , Akira Nomura¹ , Takeshi Katsu¹ , Yuji Tanaka¹ , Takaki Imamura¹^,3 , Ayumu Sakai¹^,4 and Shigetoshi Kuroda¹

¹Department of Neuropsychiatry, Okayama University Graduate School of Medicine and Dentistry, Shikata-cho 2-5-1, Okayama, 700-8558, Japan

²Nishikawa Hospital, Minato-machi 293-2, Hamada, 697-0052, Japan

³Takaoka Hospital, Nishiimajuku 5-3-8, Himeji, 670-0061, Japan

⁴Kasaoka Hospital, Imadate 2543, Kasaoka, 714-0022, Japan

author email corresponding author email

BMC Psychiatry 2003, 3:13doi:10.1186/1471-244X-3-13


Published:	21 October 2003

Abstract

Background

Several lines of evidence have supported possible roles of the sigma receptors in the etiology of schizophrenia and mechanisms of antipsychotic efficacy. An association study provided genetic evidence that the sigma receptor type 1 gene (SIGMAR1) was a possible susceptibility factor for schizophrenia, however, it was not replicated by a subsequent study. It is necessary to evaluate further the possibility that the SIGMAR1 gene is associated with susceptibility to schizophrenia.

Methods

A case-control association study between two polymorphisms of the SIGMAR1 gene, G-241T/C-240T and Gln2Pro, and schizophrenia in Japanese population, and meta-analysis including present and previous studies.

Results

There was no significant association of any allele or genotype of the polymorphisms with schizophrenia. Neither significant association was observed with hebephrenic or paranoid subtype of schizophrenia. Furthermore, a meta-analysis including the present and previous studies comprising 779 controls and 636 schizophrenics also revealed no significant association between the SIGMAR1 gene and schizophrenia.

Conclusion

In view of this evidence, it is likely that the SIGMAR1 gene does not confer susceptibility to schizophrenia.