With the development of molecular biology, it has become necessary to analyze the impact and incidence of genetic diagnosis in human health. Genetic engineering allows the handling of biological information related specifically to each individual in order to identify genetic abnormalities produced by diseases, as well as the predisposition to them. Through detailed knowledge regarding genetic configuration of individuals, it is possible to detect such human predispositions to diseases and the organic response to different infectious agents, drugs, and chemical products. However, the results of these tests may be handled inside and outside medical contexts and with different purposes; therefore, the potential social control which could result from the manipulation of biological information must be considered Thus, it is important to define who should have access to such information, taking into consideration the ethical aspects as well as the limitations of genetical research.