MOLECULAR MECHANISMS OF DEVELOPMENTAL DISORDERS

One of the central tenets of developmental psychopathology is the beli ef thar we can learn more about normal functioning through the study o f psychopathology and arrive at a better understanding of pathological conditions through investigations of normal behavior. Advances in kno wledge from one area will Inform us regarding mechanisms at work in th e other. A similar perspective is the driving force behind recent, sci entific advances in our understanding of certain developmental disorde rs. In this paper, molecular findings for four developmental disorders are reviewed: Prader-Willi syndrome, fragile X syndrome, Williams syn drome, and lissencephaly. These disorders were chosen for discussion b ecause putative genes for each of them have been isolated. The ways in which mutations within these genes disrupt normal cognitive and behav ioral functioning are discussed. Although considerable progress has be en achieved in understanding the genetic mechanisms for these illnesse s, much more research is needed to identify the environmental and gene tic factors that interact to contribute to the expression of the more complex behavioral disorders.