The main steps taken and the goals reached in the field of Human and Medicai genetics, the expected knowledge from the rapidly evolving Human Genome Project, and the new important medicai applications are briefly outlined. Then, the view of the Catholic Church on three controversial ethical problems arising from these new developments is proposed. As to the first problem, concerning the research on early human embryos, it seems clear that- whichever their origin and the type of experimentation- they are considered and treated, contrary to any other experimentation on humans, as pure producible and/or disposable objects, thus violating their human dignity and rights. As to the second problem, conceming the use of preimplantation and prenatal diagnosis with the aim to discover and abort embryos and fetuses who are or shall be affected by some serious disease, beside the patent eugenistic perspective one must recognize that they are innocent human beings who have an absolute right to life. As to the third problem, concerning the epidemiologic genetic surveillance, although this could afford a possible and plausible way of preventing the risk of affected conceptuses, it has already opened the door to a number of abuses against justice an d equity.