[Ethical reflections on xenotransplantation].

The success of transplantation and the increasing demand for donor organs have led to an increasingly acute shortage of human organs and tissue for transplantation. In this situation xenotransplantation (cross-species transplantation from animals to humans) is discussed as a possible alternative to allotransplantation. Therefore the animal plays an important role in the discussions on xenotransplantation. Currently, a lot of research is being done on xenotransplantation. Cross-species transplantation involves many biological and medical problems and risks which may affect not only the individual patient but also the wider community and population. These problems give rise to important ethical questions about xenotransplantation. Apart from them other ethical issues are involved, concerning the human being as well as the animal. Animals are raised, genetically modified (transgenic animals) and kept under SPF-conditions before they can be used as organ sources. At the moment they are used as models in xenotransplantation research. My aim is to discuss some of the major ethical, medical and biological problems of xenotransplantation.