We live in a technological age. Science and design have made it possible to have face-to-face conversations with people thousands of miles away. Hand-held devices can be at once fonts of knowledge, communication hubs, workstations and entertainment platforms without a wire in sight. Science and technology are an enormous part of most of our daily lives. But how do we feel when technology starts to create life?
Cloning has long been a hot-button issue with supporters as vociferous as the detractors. As part of our ‘Animal Welfare Month’ I’m going to be taking a look at cloning: what it is; what it’s been used for and what some say could be its future.
So, firstly, what is cloning? While science fiction would lead us to believe cloning is like copy and pasting something on the computer, the reality is rather different. The process generally involves two cells: a cell from one animal from which the nucleus is harvested, and the egg of another from which the nucleus is removed. The harvested nucleus is then injected into the de-nucleated egg with a very thin needle in a petri dish. The re-assembled egg is stimulated and, in successful cases, then splits and grows to become an embryo. When the embryo is a little bigger it is then implanted in a host uterus of a compatible animal to be carried to term and then born.
One of the perceived issues with this process is the fact that what is created is not, in the strictest sense, a clone. While the nucleus is like the genetic library of a cell there is still genetic information in the mitochondria (cell components in the remnants of the harvested egg cell). What this means is that, while the majority of the embryo’s DNA comes from the nucleus that is implanted, it will still retain some of the genetic information left in the egg. Dolly the Sheep was considered to be the first successful clone but she was more accurately a “chimaera”, an animal with two sets of DNA.
Chimaeras are present in nature, with some lobsters featuring bodies that are half one colour and half another and some chickens exhibiting hermaphroditism (a condition where an animal has both male and female organs). In fact, chimaerism is a vital part of the life cycle of the angler fish (where the male fuses with the female to reproduce). There was even a high-profile court case where a woman was charged for fraud when it was found that her children did not carry the DNA taken from her hair sample. Upon further testing it was found that her cervical DNA carried the same genes as her children and that she was a chimaera. It has been argued that this progress could be applied in a way that would lead to stronger, more evolved animals, similar to natural evolution and cross-breeding present in nature and, particularly, in dog breeding.
In 2001 the first “viable” clone of an extinct species was created. It was a small wild sheep called a European Mouflon. Since then several different critically endangered species have bene cloned, from ferrets to feral goats. Institutions have been working to create archives of genetic material, some registering their intention to use this information to “resurrect” the species in the future, or to work to reverse their declining numbers.
At first the arguments in support of this cloning are obvious; we have the potential to bring back animals that have been forced into extinction by harvesting fossilised DNA. We could also supplement ailing populations of critically endangered animals by creating more breeding opportunities and boosting the numbers. With more than sixty species currently extinct in the wild but present in captivity, could this be a way to repatriate these creatures in greater numbers and recreate lost ecosystems?
Lost ecosystems are, in fact, one of the issues with this idea. One of the reasons these animals have become extinct is because their habitats have been either greatly reduced or entirely demolished due to agriculture and urbanisation. Many species on the critically endangered list are there because of habitat destruction and resulting loss of both prey and roaming space. If we were to restore these lost populations how would we rectify this? If species were recreated where would they live?
Additionally there is some debate over whether it’s a good idea to breed cloned animals with conventionally born or, even, wild animals. It is largely held that a male clone could be mated with natural females as only their nucleic DNA is passed onto offspring, whereas a cloned female would still pass on their residual mitochondrial DNA that they got from their host egg. For example Javan Bantengs have been cloned by putting cryogenically frozen nuclei from bantengs into the eggs of cows. The embryos are carried, and eventually, born by cows. If there were two bantengs born, one male and one female, they could both in theory be bred with naturally-born bantengs, however any offspring from the female would still carry the mitochondrial DNA from the cow egg used for the embryo whereas the male would only pass on the nucleus of its sperm resulting in a “pure” banteng embryo. In the case of endangered but surviving species, in theory, a number of males of waning species could be introduced to wild communities to assist with biodiversity and to get the numbers up. But the logistics would certainly need examining; as the cloning process by nature requires a laboratory environment for much of the process the animals which result from them are not acclimatised to living in the wild. How would these unconventionally-created animals cope with being introduced to the wild, and how would they learn to interact with a species that they have been born and bred apart from?
In a world where we can use a 3D printer to create anything from a table to bacon could cloning be a way to meet the demands of the illegal trade in animal parts? Tigers, elephants, bears and rhinos are hunted for their skins and body parts for various uses. Could cloned specimens fill the demand and protect the species in the wild? It’s a bizarre notion but could merit consideration.
While there are plenty of species in sad, steady decline there have been a number of successes in conservation without cloning, for instance the tiger population in India has actually increased over the last ten years. Could raising awareness and pricking the collective conscience about the cause of conservation help save endangered animals without the need of intervention in the forms of cloning? In addition there is some debate as to whether extinct and endangered animals should be revived or propagated. Some see it as interfering with natural selection and stopping nature from taking its course. There is, evidently the counter-argument that many species have gone extinct as a direct result of human involvement and that, therefore, it is our responsibility as a species to redress the balance and undo the damage we have done to the planet and its many residents.
Ultimately the issue with cloning is that, at present, the process is not infallible. A great number of cloning attempts are unsuccessful and even animals carried to term are often short-lived. While the process itself is fatally flawed and still in the experimental is it right to consider introducing them to other animals? And is it fair on the animals from whom the eggs are harvested and who carry the cloned animals that are of a different species to them?
This is a hotly-debated, contentious issue and, as with a lot of ethical issues, there don’t seem to be any definitive answers. We would love to hear what you think, why not share your view on our on our Facebook or Twitter pages.