“Geneticization” is a term used to describe the ways in which the science of genetics is influencing society at large and medicine in particular; it has important implications for the process of diagnostics. Because genetic diagnostics produces knowledge about genetic disease and predisposition to disease, it is essentially influenced by these innovations in the disease concept. In this paper, I argue that genetic diagnostics presents new ethical challenges not because the diagnostic process or method in genetic diagnostics is ethically different (...) in kind from traditional medical diagnostics, but because it relies on a neo-ontological concept of disease in a context of genetic reductionism. Geneticization has not produced a radically new concept of disease, however, but has introduced innovations into the classical ontological concept of disease. When this new concept of disease is held in tandem with genetic reductionism, we are led to the absurd conclusion that disease is the very essence of the human being. I argue that neither the neo-ontological concept of disease nor genetic reductionism is necessary for a proper understanding of genetic diagnostics. (shrink)