One of Britain’s leading scientists has been forced to move groundbreaking organ transplant research to the United States, after he was blocked by red tape from conducting a key experiment in this country.

Restrictions on animal research have prevented a company set up by Lord Winston, the fertility specialist, from breeding pigs using a new genetic engineering technique that has the potential to produce “humanised” animal organs for transplant. Instead, the work will take place in Missouri.

The ban on the work proposed by Atazoa has raised fresh concern that the brain drain to the US is being revived by an excessive bureaucracy attached to British science.

It is also a blow to Gordon Brown’s attempts to ensure that British medical research is commercially exploited in this country rather than abroad.

Lord Winston, Emeritus Professor of Fertility Studies at Imperial College London and a director of Atazoa, said that an “unhelpful atmosphere” around animal experimentation, which has led to overzealous regulation, was discouraging investment in British medical science. “It is becoming increasingly difficult to get this work done in Britain,” he told the festival. “What I fear is that this work is bound to go on elsewhere. It is increasingly happening in the US.”

Atazoa, which Lord Winston established with Professor Carol Readhead, of the California Institute of Technology, is developing a method of genetic engineering that alters animals’ immune systems so that hearts or kidneys are less likely to be rejected after being transplanted into human patients. Pig organs could solve the shortage of organs available for transplant; more than 5,000 people need a kidney transplant each year, but fewer than 2,000 organs become available. “You are literally waiting for someone to have a motorcycle accident and die,” Lord Winston said.

The creation of transgenic animals usually involves manipulating early embryos, but Atazoa is instead altering the testes of adult male pigs so that they produce sperm containing new genes. GM animals with appropriate immune systems for transplants would then be conceived through ordinary mating.

The procedure has been successfully tested in mice, but when Lord Winston sought permission to use it to alter male pigs’ testes, the Home Office took 13 months to grant a licence. The Department for Environment, Food and Rural Affairs then banned Atazoa from using the modified male pigs to sire young, ruling that breeding from transgenic farm animals would breach a European Commission directive.

Lord Winston said: “It does seem to be blinkered as it is not work that causes suffering to animals. They actually get a bit of pleasure as they naturally mate. There is no evidence of any suffering to offspring.”

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