For the first time, a rhesus monkey (Macaca mulatta) cloned in the laboratory has lived into adulthood — surviving for more than two years so far.

The feat, described today in Nature Communications1, marks the first successful cloning of the species, and was achieved using a slightly different approach to the conventional cloning technique used to clone Dolly the sheep and other mammals, including long-tailed macaques (Macaca fascicularis), which were the first primates to be cloned.

By replacing the placenta of the cloned embryo with a placenta from embryos produced by in-vitro fertilisation, scientists were able to reduce developmental defects that often hinder the survival of cloned embryos, while using fewer embryos and surrogate mothers. The new technique could unlock possibilities for using cloned primates in drug testing and behavioural research.

“We can produce a large number of genetically uniform monkeys that can be used for drug efficacy tests,” says Mu-ming Poo, director of the Institute of Neuroscience in the Chinese Academy of Sciences in Shanghai.