"It is hard to say whether Dolly died at a relatively young age or died from defects in the process of reproduction," Du Miao, a researcher with the Biology and Growth Institute of the Chinese Academy of Sciences, told China Daily in Beijing yesterday.

"But Dolly's case reminds us that both Chinese and foreign scientists should put more efforts into improving clone technology as well as disease treatment techniques in the field of cloning animals."

He said his institute, in cooperation with Yangzhou University in Eastern China's Jiangsu Province, had cloned more than 10 sheep since 1999 and the oldest is nearly five. They are all still alive.

Li Ning, deputy director of the National Key Laboratory of Agricultural and Biological Technology, who is also a professor with the Beijing-based China Agricultural University, said: "Clone technology is actually progressing well.

"Dolly is the first cloned sheep after all. Like driving cars, new drivers are prone to accidents, but the more you drive the easier and safer you feel.

"In the future, the death rate of cloned animals will be reduced with technological developments."

Although there are no official statistics on the number of animals cloned by Chinese scientists over the past few years, at least 17 cloned cattle born between 2000 and 2002 are still alive, according to Li.

The number of cloned sheep in China is not concrete. Although some institutes have cloned several sheep, they did not pass appraisals by experts and were therefore not revealed.

Official reports show seven locally cloned sheep are still alive, Li said.

He said clone technology in China is gradually approaching a level of commercialization.

But Wang Yu, deputy director of the Biological Technology Center under the Ministry of Science and Technology, said the commercialization of clone technology depended on market demand.

(China Daily February 18, 2003)