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Tuesday, 14 March, 2000, 16:33 GMT Scientists produce five pig clones The scientists who created Dolly the sheep have announced the birth of five pig clones - the first in the world. Edinburgh-based company PPL Therapeutics hopes such animals will help meet the anticipated demand for pig organs if they are approved for use in human transplants. The five piglets, which were born on 5 March, have been named Millie, Christa, Alexis, Carrel and Dotcom. "They're wonderful, they're healthy, they're bouncing around," said PPL's Dave Ayares, who was present at the birth of the animals. The piglets were created from adult cells using "nuclear transfer" technology similar to that which led to the birth of Dolly. A company spokesman said: "This opens the door to making modified pigs whose organs and cells can be successfully transplanted into humans - the only near-term solution to solving the worldwide organ shortage crisis." Clinical trials into the use of animal organs for human transplant could start in about four years, the company said. The development has been welcomed by other scientists working the field of xenotransplation - the use animal organs for human transplant. UK-based biotech firm Imutran, which is breeding genetically-modified pigs for transplant, said: "This is interesting news. It is potentially a useful technology to develop new lines of pigs for xenotransplantation. "However, the next step is to see if the technology can be applied to developing genetically-modified animals whose organs can be transplanted into humans without being rejected." This is a reasonable aim, according to Erling Refsum, of analysts Nomura Securities: "Cloning is the most difficult step. The rest of the barriers are more easily dealt with. "Dolly was a scientific breakthrough but this is bigger. This puts them clearly up front in doing something that no one else can do. These pigs definitely put them in the big league," he added. Some analysts believe the market could be worth $6bn for the solid organs alone. Colin Blakemore, Professor of Physiology at Oxford University, looked forward to a time when such animals could also be used in novel cell therapies. "For example, cells from the pig that could be engineered to produce human insulin - they might be used to treat diabetes, a disease for which organ transplantation is not feasible at the moment," he told the BBC. He warned, however, that scientists could not escape the ethical debate that would inevitably follow from such research. But Dr Ron James, PPL's managing director, said many of the arguments had already had a good airing. "I don't see that there are any ethical implications which are new in this work," he said. "If one is happy to eat pork then I can see no real problem in using the same animal for life-saving purposes." PPL said the method used to produce the five female pigs involved new procedures developed by its US staff in Blacksburg, Virginia. The piglets' DNA has been confirmed in independent tests to be identical to the donor, but different from the surrogate mother. The names for the new clones, which were born in the US, were chosen by the scientists in Virginia. The first, Millie, was named after the millennium; Christa, after Christian Barnard, the surgeon who performed the first human heart transplant in 1967; Alexis and Carrel after transplant pioneer and Nobel prizewinner Alexis Carrel; and Dotcom to reflect the growing use of the internet. The work was part-funded by a US Government grant awarded to produce a "knock-out" pig - one which has a specific gene or genes inactivated to help prevent the human immune system rejecting an implanted pig organ. However, these genes can only be knocked-out in individual cells, not in whole animals. To generate organs with knocked-out genes, scientists must take the altered cells and use them to create clones. PPL has now proven cloning is possible and says it had already achieved the required targeted gene knock-out in pig cells, using the same patented technology that led to the gene-altered lambs Cupid and Diana. Pigs have become the central focus of attempts to produce organs for xenotransplatation. Primates would be a closer match but ethical concerns and the fact that they produce only single offspring have meant this approach has not been developed. The large litters of pigs and the similarity in size of their organs have led to their being the most likely supplier of any future transplant organs. BBC News Online: Sci/Tech http://news.bbc.co.uk/low/english/sci/tech/newsid_676000/676906.stm janet paterson 53 now / 41 dx / 37 onset a new voice: http://www.geocities.com/janet313/ 613 256 8340 PO Box 171 Almonte Ontario Canada K0A 1A0