LONDON (Reuters) - Chinese scientists have cloned monkeys using the same technique that produced Dolly the sheep two decades ago, breaking a technical barrier that could open the door to copying humans.

Zhong Zhong and Hua Hua, two identical long-tailed macaques, were born eight and six weeks ago, making them the first primates — the order of mammals that includes monkeys, apes and humans — to be cloned from a non-embryonic cell.

It was achieved through a process called somatic cell nuclear transfer (SCNT), which involves transferring the nucleus of a cell, which includes its DNA, into an egg which has had its nucleus removed.

Researchers at the Chinese Academy of Sciences Institute of Neuroscience in Shanghai said their work should be a boon to medical research by making it possible to study diseases in populations of genetically uniform monkeys.

But it also brings the feasibility of cloning to the doorstep of our own species.

“Humans are primates. So (for) the cloning of primate species, including humans, the technical barrier is now broken,” Muming Poo, who helped supervise the program at the institute, told reporters in a conference call.

“The reason ... we broke this barrier is to produce animal models that are useful for medicine, for human health. There is no intention to apply this method to humans.”

Genetically identical animals are useful in research because confounding factors caused by genetic variability in non-cloned animals can complicate experiments. They could be used to test new drugs for a range of diseases before clinical use.

Zhong Zhong and Hua Hua, two cloned long tailed macaque monkeys are seen at the Non-Primate facility at the Chinese Academy of Sciences in Shanghai, China January 10, 2018. Picture taken January 10, 2018. Qiang Sun and Mu-ming Poo, Chinese Academy of Sciences handout from Cell/ via REUTERS

The two newborns are now being bottle fed and are growing normally. The researchers said they expect more macaque clones to be born over the coming months.

Since Dolly - cloning’s poster child - was born in Scotland in 1996, scientists have successfully used SCNT to clone more than 20 other species, including cows, pigs, dogs, rabbits, rats and mice.

Similar work in primates, however, had always failed, leading some experts to wonder if primates were resistant.

The new research, published on Wednesday in the journal Cell, shows that is not the case. The Chinese team succeeded, after many attempts, by using modulators to switch on or off certain genes that were inhibiting embryo development.

Even so, their success rate was extremely low and the technique worked only when nuclei were transferred from foetal cells, rather than adult ones, as was the case with Dolly. In all, it took 127 eggs to produce two live macaque births.

“It remains a very inefficient and hazardous procedure,” said Robin Lovell-Badge, a cloning expert at the Francis Crick Institute in London, who was not involved in the Chinese work.

“The work in this paper is not a stepping-stone to establishing methods for obtaining live born human clones. This clearly remains a very foolish thing to attempt.”

The research underscores China’s increasingly important role at the cutting-edge of biosciences, where its scientists have at times pushed ethical boundaries.

Slideshow (5 Images)

Three years ago, for example, researchers at Sun Yat-sen University in Guangzhou caused a furor when they reported carrying out the first experiment to edit the DNA of human embryos, although similar work has now been done in the United States.

Scientists at the Shanghai institute said they followed international guidelines for animal research set by the U.S. National Institutes of Health, but called for a debate on what should or should not be acceptable practice in primate cloning.</s>More than 20 years after the cloning of Dolly the sheep, Chinese researchers have unveiled two monkeys cloned using the same process.

Two monkeys have caught the attention of the whole world after it was announced that the tiny long-tailed macaques are actually clones, called Zhong Zhong and Hua Hua.

Born eight and six weeks ago, respectively – and named after the Chinese adjective ‘Zhonghua’, which means Chinese nation or people – the monkeys are the first primate clones made by somatic cell nuclear transfer (SCNT).

The cloning technique was first brought to the world’s attention by Dolly the sheep in 1996, the first mammal cloned from an adult somatic cell.

The results of the latest major genetic milestone were published to Cell by a team of researchers from the Chinese Academy of Sciences Institute of Neuroscience in Shanghai, with the intention of making it possible to conduct research with customisable populations of genetically uniform monkeys.

The title of the first cloned monkey, however, goes to a rhesus monkey called Tetra, born in 1999 using a process similar to how twins are born.

How they were born

This latest SCNT breakthrough is of massive importance. The SCNT method involves removing the nucleus from an egg cell and replacing it with another nucleus from differentiated body cells.

The reconstructed egg then develops into a clone of whatever donated the replacement nucleus. In this instance, it overcame a previous hurdle whereby monkey cell nuclei had proved resistant to SCNT.

So, to tackle this challenge, the research team introduced epigenetic modulators after the nuclear transfer. These modulators switch on or off the genes that are inhibiting embryo development.

The team’s success rate increased when it transferred nuclei taken from foetal differentiated cells such as fibroblasts, a cell type in the connective tissue.

Sadly, Zhong Zhong and Hua Hua were not the first attempts at cloning with this new method, with a number of the previous clones only living for a few months after birth.

Speaking of what this breakthrough means to the science, senior author of the paper, Qiang Sun, said the team has no intentions of developing human clones, and is only interested in the benefits for clinical research.

“You can produce cloned monkeys with the same genetic background except the gene you manipulated.

“This will generate real models – not just for genetically based brain diseases, but also cancer, immune or metabolic disorders – and allow us to test the efficacy of the drugs for these conditions before clinical use.”

Meanwhile, president of People for the Ethical Treatment of Animals (PETA), Ingrid Newkirk, has taken to Twitter to strongly criticise the news, calling it “Frankenstein experiments”.</s>For the first time, Chinese scientists have created two genetically identical monkey clones using the same technique that produced Dolly the sheep – the first-ever mammal to be cloned.

Researchers at the Chinese Academy of Sciences in Shanghai have named the newborn long-tailed macaques Zhong Zhong and Hua Hua, now six and eight weeks old respectively and are growing normally for their age.

The new research is outlined in a paper published in the journal Cell.

The monkeys were born using a cloning technique known as somatic cell nuclear transfer (SCNT), which involves removing the nucleus of an egg cell from one animal and replacing it with the nucleus of a body cell from another animal.

The reconstructed egg is then implanted into a surrogate and develops into a clone of whatever animal donated the replacement nucleus.

This cloning method has proven extremely difficult in monkeys up till now, and, indeed, the researchers created several clones which only survived for a few hours after birth.

"We tried several different methods, but only one worked," says Qiang Sun, Director of the Non-human Primate Research Facility. "There was much failure before we found a way to successfully clone a monkey."

The key to the scientists' success was conducting the very delicate SCNT procedure as quickly as possible which limits damage to the egg. This technique "takes a lot of practice", according to Muming Poo, a co-author of the study.

The team plan to hone their technique and are expecting more macaque clones to be born in the coming months.

The importance of this new study, according to the researchers, is that it demonstrates the viability of producing cloned monkeys with identical genes, which would be useful as human analogues in medical research studies, [although critics may argue that this practice is unethical].

"This will generate real models not just for genetically based brain diseases, but also cancer, immune, or metabolic disorders and allow us to test the efficacy of the drugs for these conditions before clinical use," said Sun.

Zhong Zhong and Hua Hua are not the first primate clones. That honour goes to Tetra – a rhesus monkey born in 1999 using a simpler method known as embryo splitting.</s>Two baby macaque monkeys have become the first primate clones to be produced using the same approach that gave rise to Dolly the sheep, researchers have revealed.

Big eyed, fuzzy-furred and spindly-limbed, the macaques have been named Zhong Zhong and Hua Hua. Zhonghua is the official name for China, where the animals were born.



The researchers behind the development say it will allow scientists to compare macaques to others that are genetically identical except for particular genes that have been deliberately tinkered with. That, they add, will not only help researchers probe the mechanisms behind human diseases, but aid drug screening and the development of other therapeutics.



“[The] first group of monkey clones will be models for neurodegenerative diseases,” Dr Mu-ming Poo, co-author of the research and director of the Chinese Academy of Sciences’ Institute of Neuroscience, told the Guardian. He added that the clones could also help scientists probe how the behaviour of identical twins’ genes becomes more dissimilar over time as environmental modifications to their DNA build up.

Macaque monkey clones have previously been produced by splitting an embryo, similar to the way identical twins arise in nature. But the latest research makes use of a different technique known as somatic cell nuclear transfer (SCNT) – an approach that was used to produce Dolly the sheep in 1996.



This technique involves removing the nucleus from an unfertilised egg and replacing it with that from a cell taken from the body of the individual to be cloned. This is done by fusing the cell with the nucleus-free egg – a process achieved using an electric current in the case of Dolly, and part of a virus in the latest research. The resulting embryo is transferred into a surrogate mother.

So far the technique has been used to clone a menagerie of animals, including sheep, cattle, cats, mice and even dogs – the first clone of which was an Afghan hound puppy named Snuppy.



One difficulty in the approach lies in “reprogramming” the donor nucleus – a mechanism by which existing modifications to the DNA, or proteins attached to the DNA, are erased before new changes are made, allowing it to give rise to all of the different types of cells in the body.



With the issue thought to have been a key barrier in previous attempts to clone non-human primates using SCNT, the team behind the new study describe how they exposed the egg with the “new” nucleus to a cocktail of different substances which aided reprogramming, and hence the development of the embryo.

Writing in the journal Cell, the team describe how they used the technique with two different sources of nuclei – cells from an aborted macaque foetus, and cells surrounding the eggs of an adult macaque.



In total 79 embryos produced using cells from the foetus were implanted into 21 surrogates, resulting in two live baby monkeys, born by caesarean section: Zhong Zhong and Hua Hua. Using adult macaque cells as a source of nuclei, 181 embryos were implanted into 42 surrogates and again two live babies were delivered – but both died shortly after birth, possibly because of greater difficulties in reprogramming the genes.

The team say the technique is preferable to splitting an embryo, since the latter can only produce a small number of clones, and it is difficult to edit genes in the embryos with precision.

“Cloning by SCNT solves these problems,” said Poo, noting that the technique not only means a large number of clones could be produced, but that any gene editing could be done before the nuclei are inserted into the eggs.

The researchers add that while the new research brings the possibility of cloning humans closer, it is not on the table.



“There is now no barrier for cloning primate species, thus cloning humans is closer to reality,” said Poo. “However, our research purpose is entirely for producing non-human primate models for human diseases; we absolutely have no intention, and society will not permit, this work to be extended to humans.”



Robin Lovell-Badge, a group leader at the Francis Crick institute in London and expert in genetics who was not involved in the study, said cloned animals were useful in research, since it removed the problem of genetic variability, allowing the impact of a drug or procedure to be more precisely examined. “The alternative of course, which is often what you have to do, is use many more animals,” he said. 



But, Lovell-Badge added, given the success of somatic cell nuclear transfer in other animals, it was not surprising that the method worked in macaques. He is also doubtful as to whether the approach offers benefits over embryo splitting, given how few live babies were produced.

“This is so inefficient, so hazardous and unsafe, that I am not sure it is really justified, to be honest,” he said.</s>Chinese scientists have announced the successful creation of two cloned monkeys, representing a major advance in cloning practice and potentially opening the way for a revolution in animal-model lab research.



The monkeys, long-tailed macaques called Zhong Zhong and Hua Hua, are described in the journal Cell by a team led by Qiang Sun, director of the Nonhuman Primate Research Facility at the Chinese Academy of Sciences Institute of Neuroscience.

The animals were cloned using a technique called somatic cell nuclear transfer (SCNT). This was the method used to create Dolly the sheep, the first successfully lab-cloned mammal, in 1996.

Since then, it has been successfully used to clone other species, including mice and cows, but primates have remained stubbornly resistant.

SCNT involves removing the nucleus from an egg cell and replacing it with another derived from differentiated body cells. The implant then determines the animal that develops. Because it is theoretically possible to implant the same genetic information infinite number of times, it is therefore possible to produce (again, theoretically) an infinite number of identical animals – providing a perfect standardised cohort for medical research.

There have been several previous attempts to clone primates using SCNT, but all failed. Zhong Zhong and Hua Hua were created using fibroblasts, cells normally found in connective tissue. The key achievement of Sun’s team, however, was discovering how to introduce epigenetic modulators into the nucleus – effectively allowing the scientists to switch on and off the genes that control, or inhibit, embryo development.

The fibroblasts used to make the monkeys was obtained from macaque foetal tissue. The team also tried the same technique using adult cells, in which the resulting embryos were carried to term, but died only hours after birth.

“We tried several different methods, but only one worked,” says Sun. “There was much failure before we found a way to successfully clone a monkey.”

Success in part was improved through practice. As well as the complex business of enabling the fusion of egg and nucleic matter, and the introduction of the epigenetic tools, the whole procedure turned out to be heavily dependent on the speed and dexterity of the scientists.

“The SCNT procedure is rather delicate, so the faster you do it, the less damage to the egg you have,” says co-author Mu-ming Poo.

“It takes a lot of practice. Not everybody can do the enucleation and cell fusion process quickly and precisely, and it is likely that the optimisation of transfer procedure greatly helped us to achieve this success.”

Strictly speaking, Zhong Zhong and Hua Hua, are not the first cloned monkeys in history. In 1999, a rhesus monkey called Tetra was made by a team from Oregon in the US. However, the technique used was a far simpler one, called embryo splitting, which often happens naturally, creating twins, and is inherently restricted to only one reproduction.

With SCNT, the number of genetically identical Zhong Zhongs and Hua Huas is potentially unlimited.</s>Have we – and by ‘we’ I mean genetic scientists working in the field of cloning with our implicit approval due to lack of strict regulations and mandatory ethical standards, at least in China – gone too far? Some would say ‘yes’ with the news today that researchers at the Chinese Academy of Sciences Institute of Neuroscience in Shanghai have applied the technique used to clone Dolly the sheep to create genetically identical copies of macaque monkeys. Have we finally gone too far? How long before we hear “too late” to the question of whether it’s possible to do the same with a higher primate (you know which one)?

While these two monkeys are not the first to be cloned (some have been created using the split-embryo method which produces twins but is limited to four clones), they’re the first using the Dolly technique — single cell nuclear transfer – where cell nucleus DNA is placed in an egg cell that is then nurtured into an embryo. This technique is capable of making a limitless number of copies. Do we need a limitless number of identical macaques? How about identical annoying humans?

According the study, published in the journal Cell, researchers at the Chinese Academy of Sciences made 79 attempts with 127 eggs before they produced Zhong Zhong and Hua Hua – identical long-tailed macaques born eight and six weeks ago (video of the cute little babies here). That’s a pretty low success rate and it only worked when the cell nucleus DNA came from fetal cells (Dolly’s came from adult cells). However, it’s expected that the technique will be improved.

As expected, the Chinese research team assured everyone with concerns (which is pretty much everyone) that their aim is to use cloned monkeys in medical experiments to find cures for complex diseases like Alzheimer’s and Parkinson’s that are difficult to study in lab mice or non-primates. Since using monkeys and apes in medical experiments is already controversial and on the way out in other countries such as the U.S., this probably won’t help their noble cause.

What will? The scientists said they followed international guidelines for animal research set by the U.S. National Institutes of Health, but are calling for a debate on new rules for primate cloning.

It certainly doesn’t bode well that the researchers named the monkeys Zhong Zhong and Hua Hua using halves of the Chinese word Zhonghua, which means … get ready … “Chinese people.”

Are we ready to stop those of us with enough money and power to ignore laws and ethics from continuing primate cloning and beyond?

Is it too late?</s>Chinese scientists have cloned two monkeys using the same technique that produced Dolly the sheep two decades ago.

The scientists have been accused of paving the way to living human clones after creating two genetically identical monkeys.

Two identical long-tailed macaques called Zhong Zhong and Hua Hua were born eight and six weeks ago, making them the first primates, the order of mammals that includes monkeys, apes and humans, to be cloned from a non-embryonic cell.

Previously scientists have managed to ‘clone’ primates by splitting an embryo in half but the process was essentially artificial twinning rather than true cloning.

The BBC reports: Scientists say populations of monkeys that are genetically identical will be useful for research into human diseases.

But critics say the work raises ethical concerns by bringing the world closer to human cloning.

Qiang Sun of the Chinese Academy of Sciences Institute of Neuroscience said the cloned monkeys will be useful as a model for studying diseases with a genetic basis, including some cancers, metabolic and immune disorders.

“There are a lot of questions about primate biology that can be studied by having this additional model,” he said.

Zhong Zhong was born eight weeks ago and Hua Hua six weeks ago. They are named after the Mandarin term for the Chinese nation and people.

The researchers say the monkeys are being bottle fed and are currently growing normally. They expect more macaque clones to be born over the coming months.

‘Not a stepping stone’

 Prof Robin Lovell-Badge of The Francis Crick Institute, London, said the technique used to clone Zhong Zhong and Hua Hua remains “a very inefficient and hazardous procedure”.

“The work in this paper is not a stepping-stone to establishing methods for obtaining live born human clones,” he said.

Prof Darren Griffin of the University of Kent said the approach may be useful in understanding human diseases, but raised ethical concerns.

“Careful consideration now needs to be given to the ethical framework under which such experiments can, and should, operate,” he said.

Dolly made history 20 years ago after being cloned at the Roslin Institute in Edinburgh. It was the first time scientists had been able to clone a mammal from an adult cell, taken from the udder.

Since then many other mammals have been cloned using the same somatic cell nuclear transfer technique (SCNT), including cattle, pigs, dogs, cats, mice and rats.

This involves transferring DNA from the nucleus of a cell to a donated egg cell, which has had its own DNA removed. This is then prompted to develop into an embryo and implanted in a surrogate animal.

Zhong Zhong and Hua Hua are the first non-human primates cloned through this technique.</s>Two monkeys named Zhong Zhong and Hua Hua have become the first non-human primates to be cloned using the same technique as Dolly the sheep 20 years ago - somatic cell nuclear transfer.

The long-tailed macaques were born several weeks ago in a laboratory in China.

The scientists behind the cloning said the monkeys would be useful for studying diseases, including cancers and immune disorders.

But critics said the research raised ethical concerns and could potentially bring the world closer to human cloning.

Footage courtesy of: Qiang Sun and Mu-ming Poo / Chinese Academy of Sciences</s>For the first time, scientists say they created cloned primates using the same complicated cloning technique that made Dolly the sheep in 1996.

Shanghai scientists created two genetically identical and adorable long-tailed macaques. The monkeys are named Hua Hua and Zhong Zhong, a version of the Chinese adjective Zhonghua which means the "Chinese nation" or "people."

The research was published in the journal Cell on Wednesday.

These two are not the first primates to be cloned. Scientists in 1999 created Tetra, a rhesus monkey, but used what researchers consider a simpler cloning method that produces a more limited number of off spring. In Tetra's case, scientists split the embryos, much like what happens naturally when identical twins develop.

In the case of Hua Hua and Zhong Zhong, researchers used modern technology developed only in the last couple of years to enhance the technique used to clone Dolly, which is called somatic cell transfer, or SCNT. This is where scientists reconstruct an unfertilized egg. The researchers remove the egg's nucleus -- the part of the cell that contains most of its genetic information-- and replace it with the nucleus from another cell. It's then stimulated to develop into an embryo, which is transplanted into a surrogate mother. That same cell cluster can make more genetically matched animals.

When scientists made Dolly the sheep, years after she was born they used the same cell cluster to make four other sheep clones.

The SCNT technique has worked to create about 20 different animals including frogs, mice, rabbits, pigs, cows and even dogs, but there have been "numerous attempts to clone non-human primate species, but they all failed," said Mumming Poo, an author on the paper. Scientists long thought something in a monkey's genes made the technique unsuccessful. The success of Poo's team came from several factors, he said.

The team tweaked the SCNT procedure using new technology that helped with the nucleus transfer and the fusion of cells. The team spent three years perfecting the delicate procedure. Speed while performing the procedure helped, they learned, and scientists discovered clones created out of cells from fetal tissue did better than when they used adult cells.

"By optimizing the method, we obtained 79 well-developed embryos and implanted them in 21 female monkey surrogates," Poo said. That resulted in six pregnancies and the births of the two monkeys in late 2017. They hope more monkey babies will be born soon from these embryos.

Scientists unaffiliated with the experiment say the limited success rate of the procedure suggests more work is needed before this practice becomes common. "While they succeeded in obtaining cloned macaques, the numbers are too low to make many conclusions, except that it remains a very inefficient and hazardous procedure," said Robin Lovell-Badge, an embryologist and head of the Division of Stem Cell Biology and Developmental Genetics at the Francis Crick Institute.

"You do have to start with proof of principle," said Jennifer Barfield, an assistant professor in biomedical sciences at Colorado State University, about the low number of births. She is not affiliated with the new study, but is working on reproductive technology research involving buffalo. She found the work interesting and important, "particularly for primates, where success hasn't been that easy to come by."

The birth of these clones also brings up ethical issues. Humans are in the primate family. With this birth, these scientists have broken a barrier and that means the technique could, in theory, be applied to humans. The authors of the paper say they have no intention of trying and they believe their results should spark a wider discussion about the laws and regulations the world needs to regulate cloning.

Darren Griffin, a professor of genetics at the University of Kent, said "careful consideration now needs to be given to the ethical framework under which such experiments can, and should, operate." He noted, critics will evoke, "the slippery slope argument of this being one step closer to human cloning." However, Griffin said he thinks the benefits of this approach are clear and "cautious optimism is my personal response to this study. The study itself is very impressive technically."

The authors of this experiment say they will continue working to improve the SCNT approach. They also plan to watch how Zhong Zhong and Hua Hua develop physically and mentally.

They ultimately hope the creation of these clones helps researchers better understand human disease. Poo said that the Chinese government intends to dramatically increase the size of the lab and the project. He predicts within five years there should be 20 to 30 more facilities creating monkey clones. Researchers want to use additional clones to study genetic diseases such as autism, Parkinson's, Alzheimer's and Huntington's.

"Nonhuman primate research remains vital to the continuation of medical research and advances in human health," said James Bourne, an associate professor and National Health and Medical Research Council senior fellow at the Australian Regenerative Medicine Institute at Monash University, who is not affiliated with this study. "The recent description of a protocol to clone macaque monkeys by somatic cell nuclear transfer could be an important tool in medical research for understanding disease in a species genetically more comparable to humans."

The future for Hua Hua and Zhong Zhong

Hua Hua and Zhong Zhong are being bottle fed and appear to be developing normally, scientists say. They get regular physical check ups and when they are a little older, scientists will study their mental health to see if there are any problems.

"The two monkeys are very active and healthy, they progress very rapidly like human babies," author Qiang Sun said. "Every other day, they seem more active and their motor system is much more developed and (there are) no signs of abnormality."

Video from the lab of the active pair shows one monkey likes to suck its thumb. One climbs over its stuffed Hello Kitty doll attempting to figure out how to get through the top of its incubator. The other monkey seems curious about the camera documenting its every move -- that is, until it's distracted by its sibling jumping on its back.

In other words, the clones seem to be up to typical monkey business.</s>It’s now been over two decades since scientists in Scotland successfully cloned a sheep and named the newborn Dolly. In the years since, the technology that powers cloning has advanced slowly but steadily, and while many scientists fear the inevitability that one day a human clone will be created, others are pushing the field into new areas. The latest example of cloning’s ceaseless march forward is the birth of Hua Hua and Zhong Zhong, a pair of baby monkeys that are the byproduct of the first successful somatic cell nuclear transfer performed with primates.

The newborn monkeys, who are currently just shy of two months old, were created by scientists at the Chinese Academy of Sciences. Early indications are that the little fellas are doing quite well and appear perfectly healthy, but many questions about their long-term health have yet to be answered. The research was published in the journal Cell.

The monkeys were cloned using a technique that swaps out the nucleus of an egg cell for the nucleus of a cell from the animal that scientists wish to clone. That new cell then grows and multiplies to the point where it can be implanted into a female of the species where, if all goes well, it eventually forms a viable fetus.

It might sound fairly straightforward, but the work itself is incredibly difficult and success is hard to come by. Out of the 79 clone cell packages placed in 21 surrogate females, only six pregnancies resulted, and of those six only Zhong Zhong and Hua Hua actually made it to birth.

It’s a truly remarkable achievement, but the reason behind the monkey cloning program might not sit well with many in the scientific community. According to the researchers, the ultimate goal is to clone monkeys on a large scale for use as test subjects thanks to their similarities to humans. The idea being that if scientists can give the monkeys specific diseases before they’re born, like Parkinson’s, they can be used to test various treatments.

Is intentionally breeding primate clones with disease-causing mutations for the sake of testing sketchy? I’ll let you be the judge. That said, such a thing would be a hard sell in the United States and much of Europe, but Chinese regulations are notoriously lax when it comes to scientific endeavors, and there’s little doubt that the country will push ahead with the program.
Chinese scientists announce they have successfully cloned crab-eating macaques using somatic cell nuclear transfer (SCNT), making them the first primates to be cloned. The monkeys were named Zhong Zhong and Hua Hua.