Zhong Zhong and Hua Hua

cloned female crab-eating macaques

Zhong Zhong (Chinese: 中中 pinyin:Zhōng Zhōng, born 27 November 2017[1]) and Hua Hua (Chinese: 华华 pinyin:Huá Huá, born 5 December 2017[1]) are identical macaques that were made through somatic cell nuclear transfer (SCNT), the same cloning technique that made Dolly the sheep in 1996.

Zhong Zhong and Hua Hua
中中 / 华华
SpeciesMacaca fascicularis
SexFemale
BornZhong Zhong
(2017-11-27)November 27, 2017
(age &&&&&&&&&&&025556 years)
Hua Hua

(2017-12-05)December 5, 2017
(age &&&&&&&&&&&025476 years)
Shanghai, China
Nation fromChina
Known forFirst primates to be cloned using the somatic cell nuclear transfer method
OwnerQiang Sun and Mu-ming Poo, Chinese Academy of Sciences

Zhong Zhong and Hua Hua are the first cloned primates made this way. When other scientists tried to clone monkeys before this, they used donated embryonic stem cells, but Zhong Zhong and Hua Hua came from donated nuclei from fetal cells, which is harder to do.[2][3][4][5][6][7] The two baby monkeys were both born at the Institute of Neuroscience of the Chinese Academy of Sciences in Shanghai.[8]

Background

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Scientists made the first cloned mammal, Dolly the sheep, in 1996 using somatic cell nuclear transfer (SCNT). Since then, scientists have cloned 23 different kinds of mammals, including cows, cats, dogs, horses, and rats.[6] But primates have been very hard to clone. Reprogramming nuclei that have been moved from one cell to another is very difficult.[5] A monkey named Tetra (born October 1999), a female rhesus macaque, was made by a team led by Gerald Schatten of the Oregon National Primate Research Center using a different technique, called "embryo splitting," which is a way of making an artificial twin. Embryo splitting is not as hard as somatic cell nuclear transfer, and it can only be done from an embryo. So some people say Tetra is the first cloned primate and other people say Zhong Zhong and Hua Hua are.[9]

In January 2019, scientists in China said they had made five identical cloned gene-edited monkeys using somatic cell nuclear transfer, like with Zhong Zhong and Hua Hua. They also used a gene-editing Crispr-Cas9 technique that He Jiankui said was used to create the first gene-modified human babies Lulu and Nana. These monkey clones were made to study several medical diseases.[10][11]

Process

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Zhong Zhong and Hua Hua were made by scientists from the Institute of Neuroscience of the Chinese Academy of Sciences in Shanghai. Team leaders were Qiang Sun and Muming Poo.[2] They took nuclei from fiber cells of a fetal crab-eating macaque monkey or Macaca fascicularis). A fetus is an animal that has grown bigger than an embryo but has not been born or hatched yet. They removed the nuclei from egg cells (ova) and then put the nuclei from the fetal cells into these ova.[2] The team used two enzymes to change the epigenetic memory of the donated nuclei so they would act like embryonic nuclei.[5] They then put 21 of these ova with donated nuclei into surrogate mother monkeys. There were six pregnancies, and finally two living animals.[2] These monkeys were named Zhong Zhong and Hua Hua, after Zhonghua (Chinese: 中华, a Chinese name for China).[1] Although this was still not many baby monkeys born, scientists think methods could become better in the future.[5] The Scotland-based team that created Dolly the sheep in 1996 needed to try 277 times and produced only one baby sheep.[12]

The older the donated nucleus is, the harder it is to make a clone. Fetal cells are harder to clone than embryonic cells, and adult cells are harder than fetal cells. The same team of scientists also tried to clone macaques using nuclei from adult monkeys, but it did not work. They implanted 42 mother monkeys, and 22 of them became pregnant, but there were only two infant macaques, and they died soon after birth.[2]

Other ideas

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Muming Poo said the birth of Zhong Zhong and Hua Hua does show people could make human clones, but Poo does not plan to do so. Poo also says it is important because it shows somatic cell nuclear transfer could be used to make monkeys that are genetically exactly the same, for experiments. Doctors that study the human heart already use crab-eating macaques as a model organism when they study problems with the blood vessels around the heart.[13] Poo said monkeys like Zhong Zhong and Hua Hua could be used to learn more about neuroscience, Parkinson's disease, and Alzheimer's disease when he talked on the radio news program All Things Considered in January 2018.[14]

Academics who study right and wrong in science, like Insoo Hyun of Case Western Reserve University, asked if people would make human clones anyway. Poo told All Things Considered, "Technically speaking one can clone human[s] ... But we're not going to do it. There's absolutely no plan to do anything on humans."[14]

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References

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  1. 1.0 1.1 1.2 Gao, Yun (25 January 2018). "Chinese scientists clone monkeys in world first". China Global Television Network. Retrieved 25 January 2018.
  2. 2.0 2.1 2.2 2.3 2.4 Liu, Zhen; et al. (24 January 2018). "Cloning of Macaque Monkeys by Somatic Cell Nuclear Transfer". Cell. 172 (4): 881–887.e7. doi:10.1016/j.cell.2018.01.020. PMID 29395327. S2CID 206567964. Retrieved 24 January 2018.
  3. Normile, Dennis (24 January 2018). "These monkey twins are the first primate clones made by the method that developed Dolly". Science. doi:10.1126/science.aat1066. Retrieved 24 January 2018.
  4. Cyranoski, David (24 January 2018). "First monkeys cloned with technique that made Dolly the sheep – Chinese scientists create cloned primates that could revolutionize studies of human disease". Nature. 553: 387–388. doi:10.1038/d41586-018-01027-z. S2CID 4391482. Retrieved 24 January 2018.
  5. 5.0 5.1 5.2 5.3 Maron, Dina Fine (24 January 2018). "First Primate Clones Produced Using the "Dolly" Method – The success with monkeys could ignite new ethical debates and medical research". Scientific American. Retrieved 24 January 2018.
  6. 6.0 6.1 Kolata, Gina (24 January 2018). "Yes, They've Cloned Monkeys in China. That Doesn't Mean You're Next". The New York Times. Retrieved 25 January 2018.
  7. Popular sources:Briggs, Helen (24 January 2018). "First monkey clones created in Chinese laboratory". BBC News. Retrieved 24 January 2018.
  8. Staff (24 January 2018). "Meet Zhong Zhong and Hua Hua, the first monkey clones produced by method that made Dolly". Science Daily. Cell Press. Retrieved 25 January 2018.
  9. White-house, David (14 January 2000). "Scientists 'clone' monkey". BBC News. Retrieved 24 January 2018.
  10. Science China Press (23 January 2019). "Gene-edited disease monkeys cloned in China". EurekAlert!. Retrieved 24 January 2019.
  11. Mandelbaum, Ryan F. (23 January 2019). "China's Latest Cloned-Monkey Experiment Is an Ethical Mess". Gizmodo. Retrieved 24 January 2019.
  12. Genetic Science Learning Center. "The History of Cloning". University of Utah. Retrieved 24 January 2018.
  13. Kimberley A. Phillips, Karen L. Bales, John P. Capitanio, Alan Conley, Paul W. Czoty, Bert A. ‘t Hart, William D. Hopkins, Shiu-Lok Hu, Lisa A. Miller, Michael A. Nader, Peter W. Nathanielsz, Jeffrey Rogers, Carol A. Shively, and Mary Lou Voytko (10 April 2014). "Why Primate Models Matter". American Journal of Primatology. 76 (9): 801–27. doi:10.1002/ajp.22281. PMC 4145602. PMID 24723482.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  14. 14.0 14.1 *Rob Stein (24 January 2018). "Chinese Scientists Clone Monkeys Using Method That Created Dolly The Sheep". NPR. Retrieved 24 January 2018.

Other websites

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