[Predictive medicine: an ethical challenge to medical practice]

Predictive genetic tests (predictive medicine) require procedures, norms and attitudes completely different from those used in the everyday clinical practice, as a consequence of some peculiarities of the genome as compared to the universe of biological structures or processes. Some aspects are considered in particular: the relationship between the physician and the potential user of a test and the inadequacy of a directive model based on the criterion of the "benefit for the health"; the requirements and limits of an autonomous choice in predictive testing; the complexities of the balance between social responsibility and individual autonomy for genetic disorders. On the basis of these considerations it is proposed that for predictive testing no one could know about a subject more than he/she wants to know and to tell, limiting the exceptions to well defined cases.