In a groundbreaking experiment, Chinese embryologists have successfully created the first live-born primate with majority of its cells coming from a donor monkey with green fluorescence. The researchers transplanted stem cells from another monkey’s genetically different embryo into the monkey’s embryo using needle injection. This chimeric monkey, named Greenish, was a male Javan macaque that was later euthanized due to health issues.

Chimeric animals are valuable for research as they allow scientists to study human diseases and potential treatments. Unlike chimeric rats and mice, chimeric monkeys are more human-like, providing researchers with a closer model to study human diseases and physiology. The experiment involved the transplantation of stem cells that can produce all tissues and organs of an individual, which had not been attempted before with a chimeric monkey.

The creation of Greenish is a step towards modeling human genetic diseases with an animal that is closely related to us. However, there are ethical concerns surrounding the use of monkeys as model animals, especially in cases where modeling with cells or mice is also a viable option. Additionally, the early death of Greenish raises additional ethical questions about the treatment and well-being of animals used in scientific research.

Despite these concerns, experts believe that the successful creation of Greenish represents a significant advancement in the field of stem cell research and opens up new possibilities for studying genetic diseases with animals that are more closely related to us than ever before.