Easily more than a quarter of human DNA is composed self-replicating DNA in the form of long and short interspersed elements (LINEs and SINEs), miniature inverted-repeat transposable elements (MITEs), and retro-transposons. The common feature of these different kinds of DNA, known collectively as transposons, is that they are capable of replicating themselves and reincorporating themselves the human genome, though they accomplish this by different mechanisms. However, despite their ability alter the fundamental essence of our biological being, they have yet to do extensive damage to the human population or to any singular population of organism. Transposons are incapable of causing damage to large populations because when a transposon incorporates itself into the genome in a damaging location, meaning the sequence of an expressed gene or in regions important to signal the gene’s expression, it will either leave that organism unable to develop, ostensibly killing it, or render it unable to reproduce by causing sterility. Otherwise, the transposon will be incorporating itself into DNA in an individual’s somatic cells, not in sperm or eggs cells, so it is not passed onto the offspring of that individual. In this regard, transposons are forced not to act like parasites, in that their rearrangements must either be helpful or no consequence at all because of mutually assured destruction if they do not. However, this is a question of intent, something transposons and humans share: the fundamental biological imperative- to expend the least amount of energy possible to ensure the most successful reproduction, success being defined as producing generation capable of reproducing again. Because transposons only real goal is a successful reproduction, they cannot ever truly do wholesale damage to a population of organisms. In contrast, nanobots, technically defined as devices ranging in size from 0.1-10 micrometres and constructed of nanoscale or molecular components, do not inherently have these necessary constraints. Were a self-replicating nanobot without replication constraints beyond the availbility of resources created , it could have potentially crippling consequences for all life.
Unlike transposons, nanobots are not directly dependent on the survival a host- host being defined as the organism they happen to be inhabiting or the surrounding environment. Because a nanobot would not be reliant on the macromolecules (carbohydrates, lipids, and proteins) or on the intracellular machinery necessary for its replication (DNA polymerases and ribosomes) or on reproductive capabilities of its host, it would exceed the virulence of pathogenic bacteria, viruses, or transposons. Because of its size, it would not be reliant on macromolecules for either the purposes of replication or energy, like an obligately pathogenic bacterium. The hallmark of viruses, regardless of if they are RNA or DNA, is their ability to use their hosts’ ribsomes to create copies of its genetic material. Naturally, because nanobots do not utilize nucleic acids of any kind to confer their traits, they do not need to utilize genetic their host resources. Also, they are not dependent on the reproductive success of their host in any way. Instead, they merely utilize the singular molecules around them to replicate themselves and though some specific resources might be essential, because of their small size, being only a series of molecules, they are undoubtedly available, in however small a proportion. Because they are not a product of their environment, they are not dependent only on the resources present in the environment. Like an animal being introduced to an area where they have no control on their population (no predators) and no limit on their resources, they would undergo a population explosion. In order to properly construct a nanobot incapable of replicating itself to a level which is both impractical and dangerous, the architects must follow the wisdom of Plautus- “The man you want to keep bound should be chained by food and drink” -meaning that to limit the growth of the nanobots, their growth should be controlled by the resources they need to replicate.
Also, unlike biological parasites that follow the aforementioned fundamental biological imperative, nanobots would be replicating with whatever intention they were programmed to have unless of course they were imbued with artificial intelligence. In that regard, unless there is no ambiguity in the programming of a nanobot without artificial intelligence, it cannot develop a new purpose or “outlive” the purpose it has been given. Another possible problem could result from an alteration in programming, resulting an overstimulation of replication, resulting in a cancer of the environment that depletes the extant resources to keep itself alive. Similarly, a small alteration in function could result in catastrphic consequences for the host. For example, if a nanobot were designed to have antibiotic action against a specific bacteria or virus and its ability to recognize its identifier were compromised, it might take on the role of having its antibiotic action against a more ubiquitous recognition target. This is to say little of the development of purpose in an artifically intelligent nanobot and its evolution of purpose in the same situation. It might decide the bacteria is in the right or even that neither is right and that not intervening represents the will of fate more than its action. However, this is an overextension because no artificial intelligence yet exists and how it will evolve is a whole question unto itself.
The possible problems with the development of self-replicating nanobots, as in the development of all new technology, lies in both the intent and the limitations of the new technology. With seemingly limitless possibilities of nanotechnology, especially the development of nanorobotics, it seems important to denote rules, similar to those developed by Asimov, to prevent the abuse of this technology. In order to control self-replicating nanobots, which could potentially cause the same environmental damage as a swarm of locusts, it is necessary to limit the amount of replication, either by limiting their resources or similar to how telomeres limit the growth of a somatic cell line, by breaking down after a certain number of replications. Also, it is important to prevent the development of a harmful purpose in these nanobots by highly protecting the programming that would control the purpose of the nanobots, so as not to allow them to cause harm to their hosts, creators, or external environment.
