Probing the nature of child psychopathology

Conceptualizations of the importance and mechanisms of involvement of genetic factors in the etiology of child and adolescent psychopathology are undergoing major changes. In this article, an evolutionary and epidemiologic basis for such changing conceptualizations is outlined. Examples illustrating these principles are drawn from the literature of animal behavior, normal human behavior, autism, and attention-deficit/hyperactivity disorder. Implications of these findings for both etiologic and treatment studies are proposed.