[Genetic vulnerability of methamphetamine dependence].

Methamphetamine (METH) dependence show strong familial and genetic influences in family and twin studies. METH exerts its reinforcing effects by modulating monoaminergic transmission, of which dopamine is supposed to be important. Previously, experimental animals were being used to identify mechanisms of action of METH that are related to its abuse and toxicity, and genetic mouse models have also been used to define genes that may predict risk for the development of drug addiction. We found that genetic variances of dopamine transporter, dopamine receptor, micro-opioid receptor, serotonin 1A receptor, serotonin 6 receptor, and adenosine 2A adenosine receptor could be vulnerability factors for METH dependence or psychosis in the Japanese population. Genetic analysis with a genome-wide association study (GWAS)-based approach has been successful for investigating the genetic influences of METH dependence and other complex features. Collaborative studies with JGIDA and NIDA/NIH have obtained the results that the genetic vulnerability to METH dependence contributes to other major drug addiction. The genetic studies for METH dependence might help to identify the risk of individuals and to develop treatments that take advantage of individual genetic information in the future.