Neurochemical and genetic bases of psychopathology: current status.

A review, which does not attempt to be exhaustive, is presented. Evidence for the operation of genetic factors in the etiology of mental disorders, including studies of natural families, twins, and adoptees and their biological and adoptive relatives, is briefly summarized and discussed. Environmental influences are also clearly involved, and observations bearing on their nature are described. Certain neurochemical correlates of psychopathology, particularly those related to chemical neurotransmitters, are discussed. Since schizophrenia and the affective disorders are phenomenological syndromes, it is likely that they represent heterogeneous collections of more specific disorders with common symptomatic features. Attempts to delineate more homogeneous subgroups in these disorders on the basis of morphological or biochemical features have achieved some success, and an example of each approach is described.