The German Ethics Council invites international experts to a hearing on human-animal mixed-species entities

The combination of human and animal genes, cells and tissues in the laboratory raises ethical concerns about the significance and possible blurring of the boundary between humans and animals, a topic on which the German Ethics Council is currently drawing up an Opinion. This was the context of a public hearing held by the Council on 25 February 2010 to which experts from the United States, the United Kingdom and Austria were invited.

The proceedings were opened by Jens Reich, a member of the Council, who outlined the scientific basis of the creation of mixed-species entities. Next, Matthias Beck, a Catholic theologian from Vienna University, discussed the making of “cytoplasmic hybrids”, in which the nucleus of a human somatic cell was transplanted into an enucleated animal egg in order to obtain embryonic stem cells. Professor Beck considered such research, which was currently being pursued internationally, although not in Germany, to be unethical, because such hybrids were human embryos specifically created for research purposes, which were in addition damaged by the cloning process and by the residual animal genetic material in the cytoplasm. Such exploitation was incompatible with human dignity.

Robert Streiffer, a philosopher at the University of Wisconsin, Madison (United States), spoke about the moral status of animals with human cells. In his view, this status depended on whether specific – in particular, cognitive – characteristics were deemed critical to human dignity, whether only the potential for the development of such characteristics was sufficient, or whether mere membership of the genus Homo was decisive. Professor Streiffer said that if a mixed-species entity were to be accorded a changed moral status on the basis of one of these criteria, that would not yet present a fundamental problem. Instead, the crucial point was that an animal modified in this way would have to be treated with more respect, and this could prove difficult in the context of animal experiments.

Mark Greene, a philosopher and veterinary scientist from the University of Delaware (United States), argued that mixed-species entities constituted a challenge to animal ethics even without an enhanced moral status, since modified characteristics could leave such creatures without the possibility of interacting normally with members of their own species. Professor Greene stressed the need for researchers to take more account of the risks of transmission of alien pathogens by mixed-species entities and to develop better methods of investigating characteristics and behaviours relevant to the status of such entities.

John Harris, of the University of Manchester (United Kingdom), ventured to suggest that a creature’s genetic composition and the manner of its creation were irrelevant to its status as long as the entity concerned was accorded the full level of dignity consistent with its specific characteristics. In the course of their evolution human beings had undergone constant gradual changes, while also retaining many characteristics in common with other species. In this connection, Professor Harris stressed that, rather than an absolutely clear-cut boundary, there was a continuum between humans and animals. There was no reason not to be open to future changes too, even if these were brought about artificially by human action involving the abrupt mixing of human and animal genes and cells. The deciding criterion for a positive evaluation was ultimately whether an artificially created or modified creature could potentially have a better life by virtue of the mixing with other species.

In the ensuing discussion, which continued for several hours, the members of the German Ethics Council were particularly concerned with issues such as the differing criteria of dignity applied and the relative ethical assessment of different degrees of intervention involved in the creation of mixed-species entities.

Summing up the proceedings, Wolf-Michael Catenhusen, the spokesman for the working group mainly responsible for drawing up the Ethics Council’s Opinion, noted that further reflection was needed on how far qualitative modification of an animal’s characteristics and behaviour was permissible.

An accompanying written survey enabled interested members of the public to express their views on aspects of the creation of human–animal mixed-species entities to the German Ethics Council. Anyone unable to be present at the hearing and wishing to take part in the survey can download the questionnaire from www.ethikrat.org until 5 March.