Dr Kathryn Paige Harden is a psychologist and behavioural geneticist, Professor of Psychology at the University of Texas in Austin.
The Genetics of Risk-Taking and Antisocial Behavior
Behavioral genetic studies reveal a genetic predisposition for a suite of disinhibited behaviors, which include ADHD symptoms, early sexual activity, impulsivity, and substance use.
- High Heritability: Persistent childhood antisocial behavior, particularly when accompanied by callous and unemotional traits, is highly heritable, reaching up to 80% variance, which is comparable to the heritability of schizophrenia.
- Evolutionary Trade-offs: Although humans have self-domesticated to become a highly cooperative species, some level of genetic risk-taking and deviance remains essential for societal progress and innovation. Furthermore, while extreme genetic variants can cause severe mental disorders, those same genes in moderation can predispose individuals to high creativity, artistry, or entrepreneurial success.
- The MAOA Gene: Rare genetic mutations on the X chromosome, such as those affecting the MAOA enzyme, can profoundly disrupt an individual's moral faculties and lead to severe violence, underscoring the deep biological basis of morality.