Several weeks ago two identical long-tailed macaques were born in a laboratory in China. Scientists say monkeys that are genetically identical will be useful for research into human diseases, but critics say that the work raises ethical concerns about how the world is coming closer and 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.
Zhong Zhong was born 8 weeks ago and Hua Hua 6 weeks ago. Researchers say they’re being bottle fed and are currently growing normally. They expect more macaque clones to be born over the coming months. The technique of cloning the monkeys remains a very “inefficient and hazardous procedure”. Other mammals have been cloned by using the same somatic cell nuclear transfer technique. This does involve transferring DNA from the nucleus to the donated egg cell which had its DNA removed. Then prompted to develop into an embryo and implanted in a surrogate animal.
After 79 attempts, Zhong Zhong and Hua Hua were the results. Two other monkeys were initially were cloned from a different type of cell but failed to survive. Scientists have tried multiple methods of cloning but only one method worked. Since then, scientists have cloned more than 20 species—from cows to rabbits to dogs—using this technique, but the Chinese effort marks the first time that non-human primates have been cloned successfully in the same way. This is a big deal, because the cloning technique in this study may apply to other primates such as humans. However, the study’s authors stress that they have no intention of cloning humans.
Researchers say that they want to use this technique to breed macaques for biomedical research. Exact genetic copies of the same animal would reduce the variability in results when testing new drugs or other therapies. But many biomedical researchers insist that primate models are still necessary for studying complex human diseases and disorders, from Parkinson’s to HIV/AIDS to autism. “I don’t think there will ever be a way we can avoid non-human primates in biomedical research,” says Van Rompay. “If that happens, that would be great, but right now, in-vitro and computer models are not sufficient.”
The Chinese research team says that they will monitor the long-term health of Zhong Zhong and Hua Hua, including the pair’s brain development. The coauthors also say that the government of Shanghai strongly supports their research and is underwriting plans to expand their laboratory by more than tenfold. In addition, they expressed hope that Chinese society—which is rapidly shifting its views on animal welfare—will keep an open mind to conducting research on non-human primates.
“With all this improvement, along with the high standards of ethical concerns, I think that Chinese society will accept this,” says Poo. “I hope that societies in Western countries will realize once we demonstrate the cloned monkeys’ usefulness in curing disease, they will gradually change their mind.