Is personality-disorder inherited - an overview of the evidence

Genetic factors appear to be of considerable importance in determining normal variation in personality. This is suggested by family, twin, and adoption studies as well as by indirect findings based on animal and psychophysiological studies. In contrast, there is consistent evidence that the contribution of shared family environment is minimaL Despite difficulties in defining personality disorder, it appears that many types of personality disorder, in particular schizotypal personality disorder and antisocial personality disorder/criminality, are also influenced genetically. The genetic transmission of normal personality traits and disorder is most easily explained by the contribution of multiple genes of small effect rather than by single-gene inheritance. Recent advances in molecular genetics have led to the localization of genes of minor effect for some traits. This raises the possibility of detecting a molecular basis of traits and disorders such as personality and personality disorder