Abstract
Methamphetamine (METH) is an addictive stimulant drug used all over the world, and METH has long been the most popular substance of abuse in Japan. Several investigations reported that some genes were associated with METH use disorders including methamphetamine dependence and METH-induced psychosis. Also, the symptoms of METH-induced psychosis are similar to those of paranoid type schizophrenia. Therefore, it may indicate that METH-induced psychosis and schizophrenia have common susceptibility genes. In this review, we give an outline about the genetic research using Japanese Genetics Initiative for Drug Abuse (JGIDA) samples.