Rules to create gene-edited farm animals must put welfare first - review

These gene-edited piglets have been made resistant to a lethal lung disease

Regulations to allow the production of gene-edited farm animals must put welfare first, according to an independent review.

The technology allows scientists to alter DNA so as to introduce specific traits, such as resistance to disease.

The UK government is mulling proposals to allow the commercial development of gene-edited livestock in England.

An independent analysis has called for a review of the government's proposals for regulating the technology.

A report by the Nuffield Council for Bioethics warns that scrapping the current ban on the commercial development of gene-edited animals could increase livestock suffering.

The council's assistant director, Peter Mills, who was the driving force behind the report, says the government's plan to scrap the current restrictions "effectively takes the brakes off the capacity for breeders to advance their breeding programmes".

He said: "Farming is a business, and it is a requirement of breeders of farm animals to tread a line between what they can get out of it and (animal welfare). What we are calling for is for that line to be drawn more clearly."

A heat-resistant US dairy calf

Gene-editing involves inserting new DNA sequences, deleting existing ones or modifying them in the genome of a living organism. It's a more precise and targeted technology than previous forms of genetic engineering and the changes are virtually indistinguishable from natural mutations.

Those earlier forms of genetic engineering sometimes involved the insertion of a gene from a different organism at random into another living thing.

The UK is among the world leaders in the technology. Researchers at the Roslin Institute in Edinburgh have developed pigs that are immune to one of the world's costliest animal diseases, a respiratory condition known as PRRS. They are also attempting to produce African varieties of cattle that produce more milk, while a US firm has created cows that thrive in hotter conditions.

The Nuffield report acknowledges that the technology has the capacity to bring "real benefits". But Elizabeth Cripps from Edinburgh University, a member of the working group that produced the report, said that that it could also make things worse.

"Genome editing could be used to perpetuate or possibly increase the dense stocking of animals in industrialised (production)," she said.

"We would be concerned about breeding of animals that could tolerate poor conditions better without apparently having adverse health impacts."

An experiment carried out in 1989 by researchers working for the US Department of Agriculture in Beltsville, Maryland, is held up by critics as an example of how genetic science could be misused. The American scientists added a gene into the DNA of a pig that would produce a human growth hormone. The expectation was that the animal would grow faster and be leaner than normal pigs.

Old-style genetic engineering gone wrong. A gene was inserted into this pig to make it grow more than it normally would. It worked but at the cost of the animal developing serious health problems

The researchers were successful: weight gain increased by 15%, feed efficiency by 18%, and carcass fat was reduced by 80%.

But the animals suffered from several unanticipated health issues, including kidney and liver problems, uncoordinated walking, bulging eyes, gastric ulcers, heart disease and pneumonia. Supporters of gene editing say that current technology is much more targeted, and so less likely to have such disastrous consequences

EU regulations currently forbid the commercial development of gene-edited animals. But Brexit gave the UK government an opportunity to change its rules. In September, it announced a relaxation of rules governing research on gene-edited crops and an intention to bring in new regulations next year to allow food made from gene-edited plants and possibly animals to be sold in England.

The Chair of the Nuffield working group, Prof John Dupre, from Exeter University, is concerned that the approach to setting new rules by the Department for Environment, Food and Rural Affairs (Defra), is "too narrow".

"Those involved in policing must look beyond solely questions of food safety and keep in mind an overall vision of a food and farming system that supports sustainable farming and improves standards of animal welfare."

Among the Nuffield Council's recommendations are a government review of its proposals and a public consultation process that feeds into the review.

Other recommendations include the setting and enforcement of breeding standards which have been informed by the latest science, an independent body to monitor the long-term impact of genetic changes on animals and a food labelling system that contains information of breeding.

When announcing its proposal to ease restrictions on GM technologies, the Environment Secretary said he recognised that there is a strong public interest and Defra would continue to engage with experts, businesses and campaign groups as well as the public throughout the process. A spokesman said the department was taking a "step by step approach" to enable gene editing to be used commercially.

"We are starting with plants only and then reviewing the application to animals and microorganisms later.

"We are committed to proportionate, science-based regulation and we will not reduce safety or animal welfare standards."

Prof Bruce Whitelaw, who is the interim director of the Roslin Institute, is an advocate of the safe and responsible development of gene-edited animals. As a member of the working group, he signed off on the report's concerns and recommendations. And he told BBC News that proper regulation would ensure that the technology would benefit animal welfare - as well as help to feed a hungry world.

"Genome editing is a genetic technology that has much to offer agriculture. At Roslin, we have already shown that this technology can reduce the burden of disease in livestock by producing pigs resistant to the PRRS virus. If this application progresses to the farm this will have welfare benefits for the animals on that farm," he said.

"The Nuffield Report identifies the opportunity that through public dialogue we will be able to assess how this technology can be used to benefit agriculture. There is momentum and now is the time to identify how to use genetic technologies to produce a fair and responsible livestock food system."

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