Adoption and pedigree studies suggest genetic commonality across behaviors like addiction, risky sexual behavior, and violence.

“So if you have an adoptive parent who's addicted to alcohol, you are more likely to have many sexual partners. And you're also more likely to be diagnosed with conduct disorder or um be arrested for a violent crime even if you were never raised by that parent. And it's not just substance use to substance use or violence to violence or you know risky sexual behavior to risky sexual behavior. It seems that having a family history of any of these things increases your likelihood of manifesting any one of them.”