Showing posts with label monkey clones. Show all posts
Showing posts with label monkey clones. Show all posts

Chinese use Dolly science to create monkey clones

Biologists in Shanghai, China, have created the first primates cloned with a technique similar to the one used to clone Dolly the sheep and nearly two dozen other species. The method has failed to produce live primates until now.

Researchers hope to use this revised technique to develop populations of genetically identical primates to provide improved animal models of human disorders, such as cancer. The technology, described in Cell on 24 January, could also be combined with gene-editing tools such as CRISPR–Cas9 to create genetically engineered primate-brain models of human disorders, including Parkinson’s disease.

“This paper really marks the beginning of a new era for biomedical research,” says Xiong Zhi-Qi, a neuroscientist who studies brain disease at the Chinese Academy of Sciences Institute of Neuroscience (ION) in Shanghai. He was not involved in the cloning project.

But the achievement is also likely to raise some concerns among scientists and the public that the technique might be used to create cloned humans. “Technically, there is no barrier to human cloning,” says ION director Mu-Ming Poo, who is a co-author of the study. But ION is interested only in making cloned non-human primates for research groups, says Poo: “We want to produce genetically identical monkeys. That is our only purpose.”

Primates have proved tricky to copy, despite many attempts using the standard cloning technique. In that method, the DNA of a donor cell is injected into an egg that has had its own genetic material removed.

ION researchers Sun Qiang and Liu Zhen combined several techniques developed by other groups to optimize the procedure. One trick was to undo chemical modifications in the DNA that occur when embryonic cells turn into specialized cells. The researchers had more success with DNA from fetal cells, rather than cells from live offspring.

Using fetal cells, they created 109 cloned embryos, and implanted nearly three-quarters of them into 21 surrogate monkeys. This resulted in six pregnancies. Two long-tailed macaques (Macaca fascicularis) survived birth: Zhong Zhong, now eight weeks old, and Hua Hua, six weeks. Poo says that the pair seem healthy so far. The institute is now awaiting the birth of another six clones.