Are chimeras part of our future?

by Michael Akerib, InnovaX

In zoology, a chimera is an animal containing genetic material from parents of two or more distinctly different species. Chimeras are found in nature when fertilized eggs fuse or when a fertilized egg fuses with a sperm other than the one that fertilized the egg.

Chimeras can breed but only part of the genetic material is transmitted to the offspring.

There is a major difference between chimeras and hybrids. Hybrids, such as the mule, are formed from the interaction between a sperm and an ovule of two different species, while a hybrid is formed from the mixing of the cells of two zygotes.

Experiments have been undertaken of transplanting embryonic cells of a human fetus into an animal embryo. The first such human / animal chimera has reportedly been created at the Shanghai Second Medical University in China where human and rat cells were fused.

While the creation of animal / animal chimeras may have one of several objectives such as the understanding of embryonic development or the carrying of fetuses of animal of protected species, animal / human embryos while also enabling researchers to study the behavior of human cells in experiments that could not be carried out on humans, they also serve a different purpose, namely the production of human stem cells. This is particularly true in countries that do not allow the use of discarded embryos from fertility clinics for that use.

There are also several projects to use animal / human chimeras to produce cells or organs for use in patients. Thus, sheep at the University of Nevada have human liver cells.

Biologists are clearly redesigning life. Rather than redesigning our environment to suit human life, they will redesign life to suit the needs of humans.

Redesigning life starts from the premise that we can imagine and create a better world than the one we live in today.

Two types of considerations arise. The first is medical while the second is ethical.

During the process of creating a chimera by injecting human cells into an animal embryo, a major unknown remains the extent to which such cells will migrate into the various organs of the body and thus ‘humanize’ the animal. Conversely, if animal cells are introduced into a human fetus, there would be a degree of ‘animalization’ of the human. The question of degree also arises from the perspective of the observer who may, or many not, recognize the result as part of an existing species or not.

An obvious danger in transplanting cells or organs from a chimera to a human is that of transmitting animal diseases to humans. There is no obvious solution as to how this could be prevented.

We are also assuming that our knowledge of the genetic mechanisms is, or will be in the future, sufficient to prevent unexpected developments and side effects. But will this be the case?

Assuming the ideology of those who represent the people, politicians for the most part, leads them to allow the creation of chimeras and scientists are successful in overcoming the numerous technological barriers that inevitably will present themselves, a number of ethical question arise.

Ethical issues can be sub-divided as follows:

• Should men change the destiny of the race by considering genes as objects? In other words, should human selection replace natural selection thus permanently altering our relationship with our environment?




• Evolution being partly synonymous with selection through competition, at least to some extent, and assuming the chimeras cannot compete with humans, could they evolve?




• Are we creating chimeras because we understand unconsciously that the world will be devoid of other species as the world’s biodiversity is shrinking? Chimeras as ersatz of the animals we are eliminating from the face of the earth …




• Chimeras themselves become objects rather than animals or humans, and the birth process is replaced by a manufacturing process.




• If so who should hold the decision-making power to decide which genes should be kept and which altered? What role will scientists play in this process?




• Should chimeras be considered as a form of domesticated animals, pets, or rather as a human sub-species? If the latter is the case, is it less of an ethical issue to experiment on or destroy them than it is to experiment on, or destroy, human life. This is particularly true of chimeras in which human brain cells are implanted or developed in other primates.




• What kind of rights would chimeras have, considering that animal rights vary from country to country and in some are totally non-existent




• Were chimeras to breed with humans, what status would be that of the offspring?




• Could a sub-human species be thus produced to perform tasks humans refuse doing or simply to be exhibited in zoos or circuses?




• Could we create a breed of chimeras that can look forward into time and realize their own mortality?




• Are we entering an era of post-humanity where humans as we know them will serve no useful purpose any more? Will this be a harbinger of chaos with multitudes of chimeras and few, if any, real human beings?

The issues are so important that they question our very sense of morality

To these purely ethical questions, one must add religious issues, which are of quite a different nature and need not necessarily concern those of us who are non-believers, agnostics or atheists. They are therefore not covered here.

Science has always made strides forward. We know of no technology that could advance the interests of humanity that has been discarded, however dangerous its outcome could be, even when we perceived the long-term consequences of adopting it.

In fact, the final question with regards to chimeras is our willingness to live in a very different world, in other words, our acceptance of profound change. Acceptance, perhaps, rather than intention. Sliding into post-humanity rather than making a decisive well-informed step.

Thus, the successful creation of chimeras, and their adoption as an ordinary object of our technological creativity, would be an alternative foundation to a post-human society.