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Gene-gene interaction between MAOA and COMT in suicidal behavior: analysis in schizophrenia
Vincenzo De Luca1, Subi Tharmalingam, Daniel J Müller
1Neurogenetics Section, Clarke Site, Centre for Addiction and Mental Health, Department of Psychiatry, University of Toronto, 250 College Street R-30, Toronto, Ontario, Canada M5T 1R8. Vincenzo_Deluca@camh.net
Brain Research
|May 27, 2006
Summary
Genetic variants in MAOA and COMT genes were studied for their link to suicidal behavior in schizophrenia. No significant gene interactions were found to increase suicide risk in these patients.
Area of Science:
- Neuroscience
- Genetics
- Psychiatry
Background:
- Suicidal behavior is linked to changes in noradrenergic neurotransmission.
- Norepinephrine is metabolized by monoamine oxidase A (MAOA) and catechol-O-methyl transferase (COMT).
Purpose of the Study:
- To investigate if genetic variants in MAOA and COMT genes confer risk for suicidal behavior in schizophrenia.
- To examine potential interactions (epistasis) between MAOA and COMT genes in relation to suicide attempts.
Main Methods:
- Genotyping of MAOA promoter VNTR polymorphism and three COMT polymorphisms (-287A>G, Val/Met, 3'UTR C Ins/Del) in 270 schizophrenia patients.
- Analysis of associations between genetic variants and suicide attempts (n=92).
- Haplotype and epistasis analyses were performed.
Main Results:
- No significant association was found between suicide attempts and MAOA VNTR, COMT Val/Met, or -287A>G polymorphisms.
- A slight significant finding was observed for the COMT 3'UTR C Ins/Del polymorphism (P = 0.050).
- No significant epistasis between MAOA and COMT genes was detected in relation to suicide attempts.
Conclusions:
- The study suggests that epistasis between MAOA and COMT genes does not significantly influence suicidal behavior in schizophrenia patients.
- While a COMT 3'UTR polymorphism showed a trend towards significance, overall genetic interactions do not appear to be a major risk factor for suicide attempts in this cohort.
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