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D
China became the first country to clone a monkey using nonreproductive cells, reducing the need to keep lab monkeys and paving the way for more accurate, effective and affordable animal tests for new drugs.
By December of 2017, Chinese scientists had created two clone macaques named “Zhong Zhong” and “Hua Hua” by nuclear transferring of somatic cells — any cell in the organism other than reproductive cells. This was the similar technology used to create the famous clone sheep Dolly in 1996.
Tetra, a rhesus monkey born in 1999, is the world’s first evercloned monkey, but it was done using a simpler method called embryo splitting, and it could only generate four cloned offspring at a time and cannot be genetically modified to suit experimental needs, said Pu Muming, an academician at the Chinese Academy of Sciences and the director of Institute of Neuroscience, CAS. “Cloning a monkey using somatic cells has been a worldclass challenge because it is a primate (灵长类) that shares its genetic makeup, therefore all of its complexity, with humans,” Pu Muming said.
“For drug and other lab tests, scientists have to purchase monkeys from all over the world, which is costly, bad for the environment and produces inaccurate results because each monkey might have different genes,” Pu said. “By cloning monkeys using somatic cells, we can massproduce large numbers of genetically same offspring in a short time, and even change their genes to suit our needs,” he added. “This can save time, cut down experiment costs, and produce more accurate results, leading to more effective medicine.”
Sun Qiang, director of the nonhuman primate research facility at the institute, said most of the drug trials are currently done on lab mice. However, drugs that work on mice might not work or even have severe side effects on humans because the two species are so different. “Monkeys and humans are both primates, so they are much closely related and testing on monkeys is supposed to be as effective as testing on humans,” he said. This is especially useful in testing drugs for neural diseases such as Parkinson’s disease, metabolic and immune system disease, and tumour, he added. “This achievement will help China lead the world research in an international science project related to neural (神经的) mapping of primate brains,” he said. However, bio labs from the United States, Japan, and European countries are also very able, and they will quickly catch up with China after the monkey cloning technology is made public, Sun added. “This means we have to innovate continuously and work extra hard this year to stay ahead,” he said.
A
they are determined to catch up with America
B
they try to avoid competition from other countries
C
they aren’t satisfied with what they have achieved
D
they have to keep the monkey-cloning technology a secret
正确答案 :C
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