Cloning is a process of creating a genetically identical copy of an organism. It has been widely used in animal research, but cloning primates, such as monkeys and humans, has been challenging due to technical and ethical issues. However, a recent breakthrough by Chinese scientists has opened new possibilities for primate cloning and its applications.
A Healthy Cloned Rhesus Monkey
In January 2024, a team of researchers from the Chinese Academy of Sciences reported the first successful cloning of a rhesus monkey (Macaca mulatta), a species that is widely used in biomedical research because of its close genetic and physiological resemblance to humans. The cloned monkey, named ReTro, was created using a modified version of the somatic cell nuclear transfer (SCNT) method, which involves transferring the nucleus of a body cell into an egg cell whose nucleus has been removed. This is the same technique that was used to clone Dolly the sheep, the first cloned mammal, in 1996.
However, unlike previous attempts to clone rhesus monkeys, which either failed to produce live births or resulted in early deaths of the offspring, the Chinese team was able to improve the survival rate of the cloned embryos by replacing their placentas with placentas from embryos produced by in-vitro fertilization (IVF). This reduced the developmental defects and epigenetic abnormalities that often occur in cloned embryos, which affect gene expression and function. As a result, ReTro was born healthy and has lived for more than two years so far, showing normal growth and behavior.
Implications and Challenges
The successful cloning of a rhesus monkey is a major milestone in primate cloning technology, as it demonstrates that it is possible to produce healthy and viable clones of this species. This could have significant implications for biomedical research, as it could enable scientists to create large numbers of genetically uniform monkeys that can be used for drug testing, disease modeling, gene editing, organ transplantation and other experiments that require precise control of genetic variables. Moreover, it could also pave the way for cloning other primates, including humans, although this would raise serious ethical and social concerns.
Some of the ethical concerns that are associated with primate cloning are:
- The welfare and rights of the cloned animals and their surrogates, who may suffer from physical and psychological harm during the cloning process and after birth.
- The potential misuse or abuse of the cloned animals for unethical or illegal purposes, such as bioweapons, organ trafficking or human-animal hybrids.
- The moral status and dignity of the cloned animals and their donors, who may be seen as mere commodities or means to an end rather than as individuals with intrinsic value.
- The impact of cloning on biodiversity and natural evolution, which may be disrupted or altered by introducing artificial genetic copies into the environment.
- The implications of cloning for human identity and society, which may be challenged or changed by creating genetically identical or modified humans with unknown consequences.
Therefore, while the cloning of a rhesus monkey is a remarkable achievement that opens new horizons for primate research, it also poses many questions and challenges that need to be carefully considered and resolved.