The individual, the family, and genetic testing.

Genetics plays a role in every disease, yet few health care providers understand basic genetic principles or the science underlying the genetic testing process. An understanding of the science behind genetic advances is necessary, and it is equally important for health professionals to have an understanding of the complex nature of genetic testing for individuals and their families. Much of the debate about the psychological effects of genetic testing has occurred in the absence of empirical data on diseases for which predictive testing has only recently emerged. This article will review selected literature on genetic testing and its implications for the individual and the family. The responses of families and individuals to the diagnosis of a genetic disease will be reviewed, and Huntington disease will be used as the paradigm for examining issues related to genetic testing for adult-onset cancers. Literature addressing the response to genetic susceptibility for adult-onset cancers and the implications of testing children also will be explored. Finally, identification of emerging issues relevant to genetic screening will provide a framework for identifying needed nursing research in genetic testing for adult-onset cancer risk.