China makes breakthrough, successfully clones monkeys

Their names are derived from the word that Chinese people use to refer to their country.

Zhong Zhong and Hua Hua were born eight and six weeks ago. (Picture: CAS)

Researchers at the Chinese Academy of Sciences have announced that they have made a scientific breakthrough that could have vast implications. They have successfully cloned two rhesus monkeys using the same process used to clone Dolly the Sheep.

The two monkeys, named Zhong Zhong and Hua Hua, were born eight and six weeks ago respectively. Their names are derived from the word 'Zhonghua', which is how China is referred to by the Chinese themselves.

The scientific breakthrough is the method that the Chinese researchers used to clone them - called somatic cell nuclear transfer (SCNT). This is the first time that this method has been used to clone a primate.

The short-term ramification of the breakthrough is for medical testing for cures applicable to humans. This would allow for more coherent testing on multiple monkeys with similar genetic make-up. Present testing methods, mostly done on rats and mice, tend to fail as cures on humans because of vast genetic differences.

Zhong Zhong and Hua Hua are not the first primates to be cloned. That honour goes to Tetra, who was cloned in 1999 using a method called 'embryo splitting'. This is the same process that produces identical twins. This method can produce only limited number of cloned specimens.

Somatic cell nuclear transfer involves the placement of a genetically modified nucleus, many of which can be created with the same genetic markers, in any existing egg after removing the exiting nucleus. The genetic markers that then go into the development of the egg come from the modified nucleus.

"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," said Sun Qiang, Director of the Nonhuman Primate Research Facility at the Chinese Academy of Sciences Institute of Neuroscience in Shanghai.

A statement from the Chinese Academy of Sciences said other cloned monkey babies had been born earlier, but they had all died within a few hours of birth. Zhong Zhong and Hua Hua are the ones who have lived.

The scientists say they are healthy and are growing at a rate that's considered normal for monkeys of their kind.