Both male and female rats that were given THC as adolescents produced offspring that were predisposed to heroin addiction. The next generation – the grandchildren of the treated rats – also displayed altered patterns of behaviour. Yasmin Hurd’s original 2014 study found that the offspring of THC-treated rats have abnormal patterns of mRNA and protein production in their brain cells. Some of the affected proteins act as receptors for cannabis-based drugs, and are involved in compulsive behaviours and addiction.
