Dr. Moshe Szyf of McGill University explains current rodent epigenetic research into addiction in this October 2016 interview.

“What happens during the time when there’s no drug [cocaine] exposure, there’s just the memory of the original drug exposure? And we found huge epigenetics changes during this time, the time of abstinence.

It actually suggests that abstinence cannot cure addiction. It might even aggravate it.

We found out that timing is very important. Pairing the drug [a DNA methylation inhibitor] administration with the cue was critical with reversing the epigenetic effects and the behavioral effects.

Epigenetic treatment should theoretically reprogram the animal to forget or erase the epigenetic consequences of the initial exposure. And therefore the animal should be protected from addiction for a long time if indeed we found what we thought we did with epigenetic reprogramming.”

https://www.epigenomicsnet.com/users/3002-georgia-patey/videos/13003-video2