Nearly a year ago, the world met with Hua Hua and Chen Jun, the first primates cloned through a technique that could theoretically produce an unlimited number of copies.
Now a team of Chinese scientists has used the same technique to produce five branches of another monkey, genetically altered to have a disorder with multiple traumatic psychological side effects – and the study is a terrifying ethical field.
The technique used to clone monkeys is called kernel transfer of somatic cells and involves replacing the donor egg core with one removed from the cell of another animal.
With Hua Hua and Zhong Zhong, scientists downloaded their donor core from the macaque cells.
This time, however, researchers from the Chinese Academy of Sciences have used the nucleus of cells from a genetically altered monkey. In particular, they use CRISPR-Cas9 to alter the animal's BMAL1 gene, which helps manage certain circadian rhythms in some mammals while it is still an embryo.
According to both researchers, both published in the journal National Scientific Review, the procedure works.
Five newborn monkeys show a "broad spectrum of circulatory disorders", including reduced sleep, increased movement at night, behaviors similar to schizophrenia, and signs of anxiety and depression – all of which are exposed to a worrying video broadcast with research.
For monkeys and men
While the idea of purposefully subjecting the animals to the psychological stress described above is worrying, the researchers believe that the potential benefits to mankind deserve.
"Circadian rhythm disorder can cause many human ailments, including sleep disorders, diabetes mellitus, cancer and neurodegenerative diseases," said researcher Hoon-Chun Chang in a press release. "Our BMAL1 monkeys can be used to study the pathogenesis of the disease as well as therapeutic treatment."
There is also the possibility that the cloning of genetically altered animals actually reduces the number needed for research.
"Without interfering with the genetic background, a much smaller number of cloned monkeys carrying disease phenotypes may be sufficient for preclinical tests on the efficacy of therapeutic products," said researcher Mu-ming Poo.
At the same time, the study raises many ethical issues.
On the one hand, there are a large number of unsuccessful attempts preceding the birth of these five monkeys to consider – 65 surrogate mothers have embryo implants, resulting in 16 pregnancies but only five births.
Then the question remains whether any insights from the study will even turn into humans – there are not many animal studies.
"If I were in the ethics committee, I would hesitate to approve it [this research] because of the incredible damage to animals, "said bioinitiator Caroline Neuhaus Gizmodo, "I expect scientists offering this study to have very good answers to very difficult questions about their methods and the expected benefits of their research."
READ MORE: Chinese scientists for the first time cloned a genetically modified primate[[[[Scientific warning]