LONDON: Organs from pigs could be widely available for transplanting into patients in a decade, scientists say.

The first organs suitable for transplants, most likely kidneys, are expected to be ready for testing within three years and, if tests are successful, their use could be widespread by 2018.

Pigs are seen as ideal for animal-to-human transplants, xenotransplantation, and other research because of the similarity in their physiological make-up and because they get many of the same diseases, such as diabetes.

A herd of about 50 pigs is expected to be kept as breeding stock to provide organs 'to order' and to slash waiting times for thousands of people needing transplants, it has been reported.

Professor Robert Winston of London's Imperial College and his collaborator, Dr Carol Readhead of the California Institute of Technology, are leading research into transplanting animal organs into people.

They are attempting to breed pigs that have been genetically modified so that their organs can be accepted by the human body instead of being immediately rejected, Times Online has reported.

Human immune systems are quick to react to 'foreign bodies' but the scientists are confident they are close to modifying the genetic make-up of pigs to 'humanise' their organs and make animal-to-human transplants possible.

The humanisation process of the organs is expected to be achieved by breeding genes into the pigs, probably by injecting them directly into the parent boar's testicles, that provoke a greatly reduced response in the patient's immune system.

Patients who receive pig organs would have to take immune suppressant drugs for the rest of their lives, but no more than those who receive organ transplants from other people.

Dr Readhead said it was comparatively easy to bring about such genetic modification in mice, but the process is much harder in pigs and other large animals.

A 'mini-pig' weighing about 100kg has been selected for the research because, while a quarter of the size of most of those grown for the meat industry, it is big enough to have organs of a similar size to adult human beings.

Pigs are seen as ideal for animal-to-human transplants, xenotransplantation, and other research because of the similarity in their physiological make-up and because they get many of the same diseases, such as diabetes.

'Our interest was to try to make transgenic pigs for biomedical research to understand human diseases better and eventually to try to make their organs suitable for xenotransplantation,' said Dr Readhead.

Prof Winston said 'organs that might be transplantable' could be ready 'within two to three years' and on the basis that research went smoothly they would be fully licensed and tested in as little as 10 years' time. He expected the first 'proof of principle' pigs to be bred next year.

The new strain of pig, which once established would retain its genetic modifications from generation to generation, is expected to take £3 million (S$7 million) to develop over the next five years.

He said that transplants were one of several potential benefits from the research. Others include enabling drugs which today have to be tested on people during late development phases to be tested on animals as well as avoiding reactions such as those suffered during trials at Northwick Park Hospital in 2006 when six volunteers almost died.

Dr Readhead said kidneys are likely to be the first pig organs that researchers attempt to transplant into a sick human. 'The kidney is a really good candidate,' she said. 'There's a huge shortage and it would make a big difference.'