Life from a test tube

How soon will mammoths appear in zoos, and is it ethical to create copies of ourselves?

Bloomberg has recently reported that the startup Colossal Biosciences plans to clone a woolly mammoth by 2028. Scientists aim to use DNA from a mammoth calf preserved in permafrost and an egg cell from an Indian elephant, subsequently implanting the embryo into a surrogate elephant mother. This news has reignited discussions about the ethical implications of such actions, with the pinnacle of these debates being the issue of human cloning.

Following nature’s example  

In scientific circles, cloning refers to a group of methods for creating a nearly identical genetic copy of a gene, cell, or organism. It is important to note that the copy will still differ from the original. Firstly, scientists have yet to devise a way to eliminate mutations. In the case of cloning, for instance, the nucleus of the cell from which the genetic material of the clone is taken may contain some mutations that were not present in the original embryo. Secondly, the mitochondria of the clone are inherited from the egg cell donor, not the original. Thirdly, it is impossible to provide the same intrauterine conditions for the clone’s development as for the original, which affects many characteristics of the clone.  

Notably, cloning can be not only artificial. Humanity is aware of numerous cases of the natural occurrence of exact copies, some of which we encounter almost every day.

Thus, the mechanism of natural cloning underlies vegetative reproduction in plants, bacterial division, spore reproduction in fungi and algae, and fragmentation in starfish and annelid worms. The well-known Cavendish banana is also a clone. The yellow beauties grown for export do not produce seeds (one might find a seed in only one of several hundred fruits), that is why reproduction occurs artificially: plantation personnel take cuttings from existing plants and transplant them.
The birth of identical twins in humans also serves as an example of natural cloning. However, the children are clones of each other, not of their parents. Nevertheless, even they, as shown by a study published in the Nature Genetics journal, have differences.

Long road to Dolly

The first fully-fledged clone of a living organism, obtained from a somatic rather than a sex or stem cell donor, is Dolly the sheep.  
However, the copy created by Ian Wilmut and Keith Campbell at the Roslin Institute in Scotland was the result of more than a century of scientific progress. The historically first experiment in this direction was conducted by German embryologist Hans Driesch, who in 1885 divided a two-cell embryo of a sea urchin and grew two complete individuals from both parts.
Today, the list of cloned animals includes 23 species, among them a cat, a dog, a hamster, a camel, a horse, a cow, a monkey, and others. 

The most popular animal for cloning today is the dog: as of 2023, over 1,500 pets have been cloned. This is hardly surprising, as people become extraordinarily attached to their pets and do not want to part with them. The cost of cloning a pet ranges from $35,000 to $85,000. 

Well-known actress and singer Barbra Streisand, for example, had her beloved dog Samantha cloned twice. 

Reviving species  

In 2022, Chinese scientists successfully cloned the highly endangered Arctic wolf. A year later, their American colleagues announced the creation of a copy of a Przewalski’s horse stallion named Kurt, which had been cloned in 2020. Now, scientists have set their sights on an even more ambitious task — recreating species that have already vanished. There is a whole queue for species revival, including the flightless dodo bird native to Mauritius, passenger pigeons, the woolly rhinoceros, the cave lion, and, of course, the mammoth.  
Several methods have been proposed to bring the mammoth back to life. We have already mentioned the approach of the startup Colossal Biosciences at the beginning of the article. A team led by Harvard professor George Church has taken a different route, gradually replacing genes in elephant cells with mammoth genes, using DNA from frozen carcasses. However, scientists admit that it will not be possible to grow a true mammoth this way, and they have dubbed the expected outcome of the project a ‘mammophant’, meaning an Indian elephant possessing several characteristics of a mammoth: small ears, subcutaneous fat, and long shaggy hair.  
Anyway, it remains unclear why we would want a mammoth at all. So far, the only scientific explanation is that it was a kind of ‘ecosystem engineer’ for the Siberian tundra. Scientists suggest that the presence of mammoths could help recreate more favourable natural conditions, which would inevitably impact the climate of the entire planet.  

As for Jurassic Park, unfortunately, it remains an unattainable dream even in theory — DNA cannot be extracted from fossilised dinosaur bones. Moreover, the method of obtaining a genome from the blood of an ancient reptile — once consumed by a mosquito that later became trapped in amber gum — is also deemed unrealistic by biologists.

95 percent of cloning attempts end in failure

Clone, clone, out you go! 

Far more copies are being broken around the possibility of cloning a human. Technically, this is quite a challenging task, yet science already possesses the necessary resources to begin experiments today. The only issue is that humanity faces serious ethical problems in this case. Firstly, various religions continue to exert a significant influence on earthly civilisation, prohibiting humans from taking on the role of God by creating life artificially. Secondly, in order to commence the production of clones, numerous experiments need to be conducted, during which thousands of embryos and already born clones will inevitably perish.
Additionally, there is a strong stereotype that clones created from adult organism cells age more quickly. The example of Dolly is often cited, that died at the age of six, while sheep of that breed typically live for 9 to 12 years. 
Thirdly, even if the previous ethical prohibitions are lifted, there arises the problem of using the developed technology for criminal purposes. One of the main fears in this regard is the potential for creating clones with specific characteristics, such as ideal soldiers.
The status of a clone is also unclear — the entire modern legal system is built on the premise that a person has parents. But how to deal with someone’s copy?
The creation of copies of individual organs for the correction of genetic diseases is considered a promising direction in medicine. This approach can assist people with conditions such as epidermolysis bullosa, which manifests as a blistering skin disorder — doctors have the opportunity to transplant skin grown from the patient’s own cloned cells after correcting the genetic fault. In several countries, predominantly in the West, therapeutic cloning is permitted, where the development of an embryo is artificially halted, and it is used to harvest stem cells — these are employed for medical experiments or for the treatment of specific diseases.
Cloning could be both Pandora’s box and a blessing for humanity. Excessive restrictions will eventually hinder progress in this field, yet thoughtless removal of prohibitions could lead to disaster. 
Therefore, a rational approach and caution should prevail in relation to cloning, along with adherence to the ancient principle of ‘do no harm’.

FACT

In 2023, the collection of the Rijksmuseum Boerhaave museum of history and medicine in the Netherlands was enriched with meatballs made of mammoth meat. They were created by a team from the Australian startup Vow using DNA from a mammoth that died nearly five thousand years ago, aimed at drawing public attention to artificially cultivated meat.

By Anton Popov