Sir

As reported in your News story “Vatican approves use of animal transplants 'to benefit humans'” (Nature 413, 445; 2001), the Vatican's Pontifical Academy for Life has recently organized several meetings to discuss the science, theology, ethics, law and procedures for xenotransplantation (see http://www.academiavita.org for a complete account and references). Here, we draw attention to the Vatican's conclusions, and offer a Catholic view on two current debates.

The Vatican sees three issues as critical from a theological perspective. First, man has a right and duty to act within and on the created order, making use of other creatures to achieve the final goal of all creation: the glory of God through the promotion of man.

Second, in xenotransplantation the service of animals to man represents a totally new application that is not in conflict with the order of creation. Humans must answer to the Creator for the manner in which they treat animals. The sacrifice of animals is justified only if it is required to achieve an important benefit for man, including experiments on animals and/or genetic modification of them.

Third is the question of whether an animal organ in the human body modifies a person's identity. Although transplantation of the encephalon or the gonads, which are integral to personal identity, can never be morally legitimate, that of purely functional organs is legitimate.

Finally, we mention two ethical issues. First, the vast healthcare resources that would be used for xenotransplantation are justified by the urgent need to save the lives of patients. Second is the ethical need to acquire correct information on potential benefits and risks. This should be communicated to the public. By public discussion and debate, society should help to identify the conditions under which it is acceptable to invest resources and hope in this new therapeutic approach, in the light of scientific uncertainties and the urgent need for more organs for transplantation.