SHANGHAI (REUTERS, DPA) - Chinese scientists have made clones of a gene-edited macaque to aid research of circadian rhythm disorders that are linked to sleep problems, depression and Alzheimer's disease, the official Xinhua news agency said on Thursday (Jan 24).

It was the first time multiple clones had been made from a gene-edited monkey for biomedical research, the agency said. The clones were born at the Institute of Neuroscience at the China Academy of Sciences in Shanghai.

A gene-edited monkey most prone to the disorder was selected as a donor, and its fibroblasts were used to make five cloned monkeys, Xinhua said. It cited articles published by the scientists in National Science Review, a Chinese journal.

China Daily said the clones would pave the way for more research into such problems in humans, which have become a major mental health concern.

The cloned monkeys already show signs of "negative behaviour", including sleep disorders, as well as elevated levels of anxiety and "schizophrenia-like behaviours", the paper added.

Xinhua said the programme, supervised by the institute's ethics panel, was in line with international ethical standards for animal research.

The news, however, comes on the heels of a major controversy surrounding the birth of the world's first gene-edited human babies, part of a secret experiment conducted by Chinese scientist He Jiankui.

The authorities in south China said this week He had "illegally conducted the research in the pursuit of personal fame and gain", according to Xinhua. Last year, Chinese scientists also announced the birth of the first cloned monkeys, Zhong Zhong and Hua Hua, made using the same technique that gave birth to Dolly the sheep some 20 years ago.