For the first time, several cloned monkeys have been born with a deliberate genetic defect.
They are to be used for research into biorhythmic disorders, as the official news agency xinhua writes, referring to two articles in the chinese science magazine "national science review.
The five macaques – which have an identical genetic makeup – were born recently at the institute of neuroscience of the chinese academy of sciences in shanghai.
The research on cloned monkeys is focused on the so-called circadian rhythm. It has been linked, when disturbed, in humans to sleep disorders, depression, diabetes, cancer and neurodegenerative diseases like alzheimer’s disease. For the first time, scientists will have five monkeys with the same genetic background at their disposal, xinhua wrote.
Eckhard wolf from the gene center of the ludwig-maximilians-university of munich called the research result a "rough logistical achievement". If it is ethically and scientifically proven that such an experiment is necessary, he does not consider it reprehensible. But the question must be asked: "what is the benefit to man versus the suffering inflicted on the animal," he said. It is a case-by-case decision.
"There have been genetically engineered monkeys and cloned monkeys before. This has now been combined for the first time," said rudiger behr from the leibniz institute for primate research in gottingen. Behr sees the benefits in finding better cures for diseases. The genetic material of individuals of the same species differs considerably in detail. That makes it difficult to develop drugs that work for everyone. "With an identical copy, this variability is eliminated, and you get a clearer statement," says the stem cell biologist. For europe and germany he does not consider such experiments feasible. "We have no ambitions to clone apes. This is one thing that could not be communicated in germany either."
After chinese scientists were criticized for their gene and cloning experiments, the state agency now emphasized that the research program was supervised by the institute’s ethics committee "in accordance with international standards for animal research". The publication follows the scandal surrounding a chinese researcher who in november announced the world’s first birth of genetically engineered babies. A woman is still pregnant. His experiment has sparked worldwide acclaim.
A government investigation report on monday said that researcher he jiankui had acted illegally. He has raised funds on his own and escaped the supervision of his university. The scientist had announced on youtube that he had manipulated embryos with the genetic scissors crispr/cas9 in order to make them resistant to the aids pathogen HIV. The twins nana and lulu were born healthy.
The cloning of monkeys, which was successfully carried out for the first time in china in 2017, is also controversial because the primates are so similar to humans, raising concerns about the use of the method on humans. The xinhua state agency reported that in the new experiment with the monkeys in shanghai, researchers had eliminated the crucial substance BMAL1 for regulating biorhythms by altering the genes at the embryonic stage in order to create a suitable DNA donor. Then a gene-modified monkey was selected that showed the clearest genetic disease characteristics.
Its fibroblasts had been used for cloning. For this purpose, the cell nucleus was transferred into a nucleus-less egg cell. It is the same method that was used to clone the javanese monkeys zhong zhong and hua hua for the first time in 2017. About 22 years after the birth of the cloned sheep dolly, monkeys were cloned in shanghai at that time. Although this technique had been successful in more than 20 animal species, such as cows, pigs and dogs, researchers had previously failed with monkeys.
While fibroblasts from an aborted cervix had been used, the researchers had now used a genetically modified male monkey. "It shows that in addition to a photus, a gene-edited male monkey can also be used for bundled cloning," said qiang sun from the institute. The move shows that china’s cloning program is maturing. The institute’s director, muming poo, said research would focus on models of cloned monkeys with various brain diseases. They will also be used to test the efficacy of medicines.