Cloned Rhesus Monkey Survives Into Adulthood For The First Time(representative image: pixabay)
After many failed attempts, researchers in China have successfully cloned a rhesus monkey using an innovative method that addresses common developmental defects observed in cloned embryos.
Retro is the only species of primate that scientists have been able to clone successfully. He was born on July 16, 2020.
Surviving for more than two years, ‘retro’- the rhesus monkey has successfully lived into adulthood. This marks the first successful cloning of the species. This milestone in gene technology was achieved by using a slightly different technique than the one used to clone Dolly the sheep.
The researchers replaced the placenta of the cloned embryo with a placenta from embryos produced by in-vitro fertilization. The new technique now developed can be used for drug testing and behavioral 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, says Nature.
The standard technique used is known as somatic cell nuclear transfer (SCNT). In the process, the nucleus of a body cell is transferred into an egg cell whose nucleus has been removed which typically results in extremely low birth and survival rates for cloned embryos.
But in the new technique, instead of using the entire cloned embryos, including the part that forms the placenta, which is the outer layer, the scientists only used inner cells. The extracted layer is later transferred to the non-cloned outer embryo. This successfully helped in the creation of a “natural embryo” by keeping its cloned nature within.
Using the approach, the scientists created 113 cloned rhesus monkey embryos and implanted 11 of them into seven surrogates which resulted in two pregnancies. One of the pregnant surrogates gave birth to a healthy male rhesus monkey named ReTro. While the other carried twins, who died on the day 106 of gestation.
The researchers have said that being able to successfully clone monkeys might help accelerate biomedical research given that there are limitations on what scientists can learn from lab mice, reports CNN.
Dr Lluis Montoliu, research scientist at the National Centre for Biotechnology, who wasn’t part of the research said that the cloning of both species of monkey demonstrated two things. Firstly, it is possible to clone primates and secondly, it is extremely difficult to succeed with these experiments, he said.
