A related set of developing tools also centers on the mouse: identifying the neural basis of complex behaviors. The mouse has become a critical model in studying human disease because scientists have access to many inbred strains, each expressing distinctive physiological and behavioral characteristics. Researchers can now insert, knock out, or mutate mouse genes, quickly breed a generation that expresses the change, and then see how it affects behavior. When illness-linked genes are discovered, they will be inserted and expressed in mice to find out what they do at the molecular, cellular and behavioral levels. Researchers will be able to track a wiring abnormality, a cell migration abnormality, or other anomaly that may lead to symptoms in humans.
