Vassoler et al. (2013)

I think that this paper was interesting in that Vassoler et al. (2013) found a possible pattern of inheritance of cocaine-resistance in rats.  The authors compared the behavioral and epigenetic effects of paternal cocaine self-administration and saline self-administration on adult offspring.  Male cocaine-sired rats were not as motivated to receive cocaine doses as the other groups.  Vassoler et al. (2013) think that the reinforcing effects of cocaine decreased in this group of mice.  However, this effect might also be due to differences in gonadal hormones between male and female rats.

The authors then showed that parental intake of drugs affected the post-transcriptional modification of genes in male rats.  After all, the amount of BDNF mRNA expression significantly increased in males after cocaine administration.

This paper provides evidence that there are epigenetic sex differences that change cocaine-seeking behavior.  In addition, cocaine-induced changes in physiology can be genetically passed down from fathers to sons.  However, I think that the epigenetic component is only a small one when it comes to individual differences in reactions to cocaine.  There are still many other genetic and environmental factors to consider.  I would have liked to see maybe a social stress paradigm, like in the Holly et al. (2012) paper, that might account for one component of environmental effects.