Abstract: Drug addiction induces long-term changes in the structure and function of the addiction-related circuitries. Recent studies suggested that drug abuse induced the changes of DNA methylation and gene expression in addiction-related nuclei by modulating the expression of three types of DNA methyltransferases (DNMTs) without changing DNA sequences, which in turn changed the functional neural plasticity. Therefore, DNA methylation is regarded as one of the possible mechanisms underlying persistent addictive behavior. In this review we discuss recent advances in our understanding of how DNA methylation contribute to the addictive behavior and how abusive drugs regulate the DNA methylation, and further proposed a few important directions for future research in the field.

Key words: drug addiction, DNA methylation, DNA methyltransferases (DNMTs)