can this be done safely and ethically?

Genetic engineering is nothing new. By crossing plants and interbreeding animals, our Stone Age ancestors realized they could increase the amount of food they produced.

Modern genetics allows scientists to do much more: make precise, targeted changes to the DNA of organisms in the laboratory. And this, they argue, will lead to the emergence of new, more productive and disease-resistant crops and animals.

The science is still in its infancy, but genetically modified foods have already appeared on store shelves in Japan: tomatoes high in a chemical that supposedly promotes calmness, red sea bream with more edible flesh and blowfish that grows faster.

In the US, companies are also developing heat-resistant cattle, pitted cherries and pitted blackberries.

Proponents of the technology say it could reduce disease and suffering in animals and lead to a reduction in the use of antibiotics. They also believe the technology could help combat climate change by reducing emissions of the greenhouse gas methane, which is produced by livestock such as cows, goats and deer when their stomachs break down tough fibers such as grass during the digestion process.

However, opponents argue that gene editing has not yet been proven safe and that they remain concerned about the implications for animal welfare.

Now legislation allowing the sale of genetically modified food in the UK has been stalled, with some British scientists warning other countries could be overtaken.

The new Labor government has promised to work more closely with the European Union, particularly on regulatory issues that could impact trade. The EU currently has much stricter rules regarding the commercial sale of genetically edited and genetically modified crops.

The EU set strict rules on genetically modified (GM) crops decades ago due to safety concerns and public rejection of the technology. The same rules apply to genetically modified crops.

But to scientists, the terms “gene editing” and “gene modification” mean different things.

GM, a much older technology, involves adding new genes to plants and animals to make them more productive or resistant to disease. Sometimes these new genes come from completely different species, such as when a cotton plant was given a gene from a scorpion to make it taste bad to insects.

In contrast, gene editing involves making more precise changes to the DNA of a plant or animal. Often these changes are very minor and involve editing sections of DNA to a form that, according to supporters of this technology, could be obtained naturally, for example, through traditional crossing, only much faster.

Frustrated hopes

The UK, along with the US and China, is among the world's leading countries in gene editing. Last year, the previous government passed the Precision Breeding Act, which paved the way for the commercial sale of genetically modified food in England.

At that time, many scientists working in this field were overjoyed.

“I thought, ‘Great, this will open up a whole field of activity in the public and private sectors, and we can create a gene editing entrepreneurial community in the UK,’” says Professor Jonathan Napier of Rothamsted Research, a government agricultural research institute in Harpenden.

But, he says, his hopes were soon dashed.

In order for the law to come into force, secondary legislation was needed, which was due to be passed by Parliament in July this year. But due to earlier-than-expected elections, the issue was not brought to a vote by members of parliament, and the law is currently in limbo.

Professor Napier was among 50 leading scientists who wrote to newly appointed Department of Food and Agriculture (Defra) ministers at the end of July asking them to act “swiftly and decisively” to pass secondary legislation.

Last week Defra's responsible minister, Daniel Zeichner, responded to the scientists' request by saying the government was “currently considering how to develop the regulatory framework set out in the Act and will soon share our plans with key stakeholders.”

One of the initiators of the scientists' letter, leading expert Professor Tina Barsby, called the minister's response “encouraging” but noted that his promise to clarify “soon” should mean really soon.

According to her, other countries are implementing their plans to create genetically edited crops at great speed. Thailand recently joined Canada, Australia, Japan, Brazil, Argentina and the United States in passing regulations regarding gene editing.

Even New Zealand, which Professor Barsby said has “historically taken a more cautious approach to regulating genetic technologies”, has announced it will also introduce new legislation.

Professor Barsby added: “With our world-leading scientific base in genetic research, we cannot afford to be left behind.”

But Defra ministers must also take into account the views of environmentalists such as Dr Helen Wallace of Genewatch UK, who are concerned about the “undesirable consequences” of the Precision Breeding Act.

“If you take these plants and animals out of the GM law, you don't have the same degree of risk assessment, you don't have labeling, and you risk markets because many of them regulate them as GMOs,” she says. .

Dr Peter Stevenson, Chief Policy Adviser at UK-based Compassion for Global Agriculture [Compassion in World Farming, CIWF]also fears that the technology will lead to further intensification of livestock farming – with negative consequences.

“The use of selective breeding over the last 50 years has led to a huge number of animal welfare problems,” he says.

Chickens began to grow so quickly that their legs and hearts could not properly support their rapidly developing bodies, and as a result, millions of animals suffered from painful leg diseases and others from heart disease. Do we really want to speed up this process with gene editing?”

CIWF's biggest fear is that gene editing animals to make them more resistant to disease will leave the industry unmotivated to tackle the conditions that cause animals to get sick in the first place – such as overcrowding and unsanitary conditions.

The intensity of milk, meat and egg production currently leaves many animals “emaciated and broken”, Mr Stevenson told BBC News.

Any genetic change in an animal can have negative consequences. But advocates argue that for any commercial use, companies must demonstrate to regulators that their changes do not harm animals and back that up with data.

Indeed, many who advocate the use of gene editing technology do so in part for animal welfare reasons – it could make farm animals more resistant to disease, and since fewer animals will die as a result, fewer will be needed.

Among the letter's signatories is Professor Helen Sung, who pioneered the use of gene editing to develop resistance to bird flu in chickens.

“With a virulent strain of PRRS decimating swine herds in Spain, African swine fever moving into northern Europe, and avian influenza virus detected in dairy cattle and their milk in the United States, it is important to use all possible solutions, including precision breeding, it’s hard to overstate,” she said in response to Mr. Zeichner.

Some of the solutions to the problems that Professor Sang mentions are already waiting in the wings. She works at the Rosslyn Institute, where Dolly the sheep was cloned almost 30 years ago. He now leads the world in developing gene-edited animals.

Six years ago, Professor Sang's colleagues in Roslyn developed a strain of pigs resistant to PRRS disease.

They cannot yet be sold to British pig farmers, but the British company Genus, which commercializes PRRS-resistant pigs, has received approval for their use in Colombia.

The company has also filed an application to bring the pigs to the U.S. market, which, if given the green light, could be approved as soon as next spring. Genus also plans to seek approval to commercialize its gene-edited pigs in Canada, Mexico and Japan.

Despite the well-reasoned opinions on both sides, it appears that there is room for consensus on some areas of application of the technology.

For example, CIWF's Mr Stevenson believes gene editing can be used ethically. To do this, he says, it must meet three criteria: the likelihood of any changes causing harm to animal welfare must be minimal; its ends cannot be achieved by less intensive means; and it will not have the effect of entrenching industrial animal agriculture.

According to Mr Stevenson, pigs resistant to PRRS could meet all three requirements under certain circumstances – such as efforts to use gene editing to allow the egg industry to produce only female chicks to avoid the need to kill billions of chicks every year males when they are only one day old.

Professor Mizek Chagunda, director of the Center for Tropical Genetics and Health, which is also based at the Roslin Institute, also believes in the positive potential of gene editing and believes it needs to be closely monitored.

He says the technology could improve the lives of the world's poorest farmers: “70-80% of farmers are small-scale farmers with two or three animals.” A devastating disease can leave a farmer and his family with nothing. “So providing them with animals prepared using these technologies will help protect them from this huge risk to their livelihood,” says Professor Chagunda.

However, Professor Chagunda warns that for this technology to be accepted by the public, good and reliable regulations must be developed. “Some changes may be too experimental and we shouldn't do them,” he says. “Scientists must work with regulators to get the quality products that farmers and consumers want. We must do science that is ethical and at the same time helps humanity.”

The gene editing work at Roslyn is led by its director, Professor Bruce Whitelaw, who was a scientist at the institute when Dolly the sheep was cloned. He has had to explain the potential benefits of seemingly troubling technological developments in the past, and he believes there is a pressing need now.

“We are world leaders in this technology and at the forefront of its development,” he says. “If we don't have appropriate legislation, then our powers will gradually be lost and we will lose investment, scientific talent and the impetus for developing our economy to other countries.”