Pig to human transplants Alternatively, he said, the technology could be used to make animal models of human illnesses on which new treatments could be tested. This is often done in mice but the rodents do not always mimic diseases and symptoms accurately, Dr Coleman said. Sheep might be a much better model. Dr Coleman said the scientists also hoped to produce selectively modified pig clones within the next year. PPL Therapeutics announced in February that it had succeeded in creating five pig clones - a much harder task than producing sheep.
Pigs have a gene which triggers a severe rejection response when their tissue is put in humans.
Ethical issues There will be many who will oppose the use of animals in this way, whatever the benefits to humans. Dr Donald Bruce, Director of the Society Religion and Technology Project of the Church of Scotland, said that just because a procedure was technically possible did not mean it was ethically correct. Xenotransplantation represents a completely different way of using animals from anything humans have done before.