An association study of monoamine oxidase A (MAOA) gene polymorphism in methamphetamine psychosis.

Department of Psychiatry and Neurology, Hamamatsu University School of Medicine, Higashi-ku, Hamamatsu, Shizuoka 431-3192, Japan.
Neuroscience Letters (Impact Factor: 2.03). 06/2009; 455(2):120-3. DOI: 10.1016/j.neulet.2009.02.048
Source: PubMed

ABSTRACT Methamphetamine continues to be the most widely abused drug in Japan. Chronic methamphetamine users show psychiatric signs, including methamphetamine psychosis. Monoamine oxidase A (MAOA) is one of the major enzymes responsible for the degradation of neurotransmitters. Abnormalities in MAO levels have been related to a wide range of psychiatric disorders. We examined whether or not the MAOA-u variable-number tandem repeat (VNTR) has a functional polymorphism in methamphetamine psychosis and whether or not such a polymorphism is related to the prolongation of psychosis. As expected, there was a significant difference in the MAOA-u VNTR between males with persistent versus transient methamphetamine psychosis (p=0.018, odds ratio (OR)=2.76, 95% CI: 1.18-6.46). Our results suggest that the high-activity allele class of MAOA-u VNTR in males may be involved in susceptibility to a persistent course of methamphetamine psychosis. We found no differences among females. The sample size of females with methamphetamine psychosis was too small to have significant analysis.

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