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By CCTV reporter Su Yuting

Cloning is a controversial and decisive issue that has split public opinion regarding its potential benefits versus¹ the ethical² issues it raises. In recent years, scientists have been using the cloning of pigs for medical research. But now China is using a low-cost, and efficient technique, dubbed³ "handmade cloning" to mass-produce cloned pigs.

Our reporter Su Yuting went to Shenzhen in southern China to visit the company BGI, the world's largest center for the cloning of pigs, to find out more.

They may look like ordinary pigs, but they’re far from it. Each is carrying cloned embryos⁴. Many are clones themselves. In China, the cloning of pigs has become far easier and efficient, with the application of mass production.

“We implant⁵ the embryos into the sow’s uterus. The surgery takes about a hour. Our team can do two implantations a day. The success rate is about 70 to 80 percent. We will take special care of these sows in an observatory⁶ room to ensure it recover safe and sound.” Technician Li Dongyin said.

Pigs are very similar to humans in terms of their genetic⁷ structure and body function. Every single one of these cloned pigs is genetically⁸ identical. They serve as useful models for treating chronic⁹ diseases and helping¹⁰ pharmaceutical¹¹ companies develop effective drugs that could be used on humans.

About 500 cloned pigs are produced here every year. Experts say the technology of “hand-made cloning” is the key for achieving cloning on an industrial scale.

“For hand-made cloning, it has three very crucial advantages. First, it’s very low cost, not only for the equipment but also for human resources, we don’t need to invest too much. And second, it’s highly efficient. The efficiency rate is very high compared to traditional cloning. And third it’s very easy to learn and this technology is very easy to transfer to other places. Based on these three points, we can really help pharmaceutical companies produce disease models at very low cost.” Du Yutao, vice¹² president of BGI Healthcare, said.

“This in my mind and I think across the world for many scientists' minds, creates incredible resources that very few places can do. And so, China encourages the cloning of pigs for the purpose of medical studies is really fantastic.”

Scientific innovation is one of the major driving forces in our world today. But the issue of cloning has long been controversial, and only time will tell if the debate over its pros¹³ and cons¹⁴ will be finally resolved.