'Pig 26': Can this little piggy win over the enemies of GM?

17 years after Dolly the cloned sheep, Roslin researchers announce another milestone in ambitious project to produce disease-resistant animals

Science Editor

Scientists have developed a new method of creating genetically-modified animals that addresses one of the principal objections of the anti-GM movement.

The "gene-editing" technique is at least 10 times more efficient than existing GM technology and crucially does not involve the use of antibiotic-resistance genes, which has been heavily criticised by opponents.

Researchers at the Roslin Institute in Edinburgh, where Dolly the cloned sheep was created in 1996, announced today that they have created the first GM pig with the technique as part of an ambitious project to produce disease-resistant animals by genetic engineering.

The male piglet, designated "pig 26" and born last August, has been genetically engineered with the smallest of DNA mutations - a single deletion of one out of the 3 billion chemical "letters" of its entire genome.

Scientists said that the power of the new gene-editing technique is that it is extremely precise and improves the efficiency of creating GM animals by ten-fold or more.

It can be performed on fertilised eggs rather than ordinary tissue cells and does not need the antibiotic resistance "markers" and the elaborate cloning process that previous techniques relied on to produce GM animals.

Professor Bruce Whitelaw of the Roslin said that the new technique produces GM animals with between 10 and 15 per cent efficiency compared with an efficiency of less than 1 per cent for the standard method of genetic engineering.

"We can do it without any marker or trace. Unless you do an audit trail there is no way that you would know how that mutation happened. It could have happened naturally, or by a DNA editor," Professor Whitelaw said.

In effect, because the new gene-editing technique does not leave any mark in the animal's genome other than the desired mutation, it merely mimics the natural evolutionary process but using a man-made genome editor.

"With the new technology we can work directly within the zygote [fertilised egg] with an efficiency of 10 to 15 per cent. In a litter of pigs at least one of the animals will have the edited event," Professor Whitelaw said.

"We can get rid of antibiotic resistance and for some situations we can get rid of cloning or nuclear-transfer technology as well. I think cloning does have some baggage attached to it," he said

"We as scientists are very excited about this because of very precise changes, and we see this as very powerful, but whether the public will see that as inherently different is another matter altogether," he added.

Pig 26 is part of a research programme to create GM pigs that are resistant to infections such as African swine fever virus. Scientists are trying to introduce specific DNA mutations into domestic pigs that are known to impart disease resistance to wild pigs in Africa, which do not cross breed with the European domestic pigs.

"Pig 26 has a specific single-base deletion. Out of its 3 billion bases, we have removed one exactly from where we wanted it to be removed. It's extremely easy to do," Professor Whitelaw said.

"This, in essence, is clean genetic engineering, if you want to call it that, and this is what is making commercial companies so excited and it's also going through the minds of the regulators at the minute to find a way of classifying it," he said.

Public opposition to GM food has halted the introduction of the technology in both crops and farm animals. However, a GM salmon could soon be the first GM animal to be declared officially safe to eat in the United States.

The powerful US Food and Drug Administration is near to making a decision on whether to allow Aquabounty Technologies of Massachusetts to produce its GM Atlantic salmon, which has an additional fish gene to make it grow faster all year round.


The first genetically-modified animal approved for human consumption is likely to be a fast-growing GM salmon produced by Aquabounty Technologies of Massachusetts.

The US Food and Drug Administration (FDA) is expected to make a decision on the application later this year but has already ruled that there are no major health or environmental risks.

If approval is given, there are about 40 or 50 other GM animal proposals that will be put forward for regulatory approval, said Professor Helen Sang, who works on GM chickens at the Roslin Institute in Edinburgh.

"To feed a growing population that wants more meat in its diet will require all the tools we can lay our hands on to increase the efficiency of food production," Professor Sang said.

Professor Sang and her colleagues have already produced GM chickens that are partially resistance to influenza viruses, which are a huge problem for poultry farmers - 22 million chickens infected with H7N2 flu virus were slaughtered last year in Mexico alone.

"The GM chickens succumb to the disease themselves, but they don't transmit it on. This is just the first step using genetic modification in making birds completely resistant to flu and we are carrying on developing this approach," Professor Sang said.

"It's highlighted that you can use genetic modification to protect poultry, a very important food animal, in a way that cannot be achieved using conventional breeding," she said.

"We predict that this kind of genetic modification will protect against all strains of bird flu and we also predict that if we put this gene into pigs it would also protect against swine flu," she added.

Other GM animals include cows that produce milk with no beta-lactoglobulin, a protein linked with allergies in children. Chinese scientists are also working on GM cows that produce milk rich in omega-3 fats, normally found in fish.

Start your day with The Independent, sign up for daily news emails
ebooksA special investigation by Andy McSmith
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Bookkeeper / Office Co-ordinator

£9 per hour: Recruitment Genius: This role is based within a small family run ...

Recruitment Genius: Designer - Print & Digital

£28000 - £32000 per annum: Recruitment Genius: This Design and marketing agenc...

Recruitment Genius: Quantity Surveyor

£46000 per annum: Recruitment Genius: This property investment firm are lookin...

Recruitment Genius: Telesales / Telemarketing Executive - OTE £30k / £35k plus

£18000 - £35000 per annum: Recruitment Genius: This company specialises provid...

Day In a Page

The difference between America and Israel? There isn’t one

The difference between America and Israel? There isn’t one

Netanyahu knows he can get away with anything in America, says Robert Fisk
Families clubbing together to build their own affordable accommodation

Do It Yourself approach to securing a new house

Community land trusts marking a new trend for taking the initiative away from developers
Head of WWF UK: We didn’t send Cameron to the Arctic to see green ideas freeze

David Nussbaum: We didn’t send Cameron to the Arctic to see green ideas freeze

The head of WWF UK remains sanguine despite the Government’s failure to live up to its pledges on the environment
Author Kazuo Ishiguro on being inspired by shoot-outs and samurai

Author Kazuo Ishiguro on being inspired by shoot-outs and samurai

Set in a mythologised 5th-century Britain, ‘The Buried Giant’ is a strange beast
With money, corruption and drugs, this monk fears Buddhism in Thailand is a ‘poisoned fruit’

Money, corruption and drugs

The monk who fears Buddhism in Thailand is a ‘poisoned fruit’
America's first slavery museum established at Django Unchained plantation - 150 years after slavery outlawed

150 years after it was outlawed...

... America's first slavery museum is established in Louisiana
Kelly Clarkson: How I snubbed Simon Cowell and become a Grammy-winning superstar

Kelly Clarkson: How I snubbed Simon Cowell and become a Grammy-winning superstar

The first 'American Idol' winner on how she manages to remain her own woman – Jane Austen fascination and all
Tony Oursler on exploring our uneasy relationship with technology with his new show

You won't believe your eyes

Tony Oursler's new show explores our uneasy relationship with technology. He's one of a growing number of artists with that preoccupation
Ian Herbert: Peter Moores must go. He should never have been brought back to fail again

Moores must go. He should never have been brought back to fail again

The England coach leaves players to find solutions - which makes you wonder where he adds value, says Ian Herbert
War with Isis: Fears that the looming battle for Mosul will unleash 'a million refugees'

The battle for Mosul will unleash 'a million refugees'

Aid agencies prepare for vast exodus following planned Iraqi offensive against the Isis-held city, reports Patrick Cockburn
Yvette Cooper: We can't lose the election. There's too much on the line

Yvette Cooper: We can't lose the election. There's too much on the line

The shadow Home Secretary on fighting radical Islam, protecting children, and why anyone in Labour who's thinking beyond May must 'sort themselves out'
A bad week for the Greens: Leader Natalie Bennett's 'car crash' radio interview is followed by Brighton council's failure to set a budget due to infighting

It's not easy being Green

After a bad week in which its leader had a public meltdown and its only city council couldn't agree on a budget vote, what next for the alternative party? It's over to Caroline Lucas to find out
Gorillas nearly missed: BBC producers didn't want to broadcast Sir David Attenborough's famed Rwandan encounter

Gorillas nearly missed

BBC producers didn't want to broadcast Sir David Attenborough's famed Rwandan encounter
Downton Abbey effect sees impoverished Italian nobles inspired to open their doors to paying guests for up to €650 a night

The Downton Abbey effect

Impoverished Italian nobles are opening their doors to paying guests, inspired by the TV drama
China's wild panda numbers have increased by 17% since 2003, new census reveals

China's wild panda numbers on the up

New census reveals 17% since 2003