‘Genetic engineering’ implies an act of engineeringFriday, 6 February, 2009
The term genetic engineering, according to Wiktionary, is the “the deliberate modification of the genetic structure of an organism.” Other definitions, especially those used by biotechnology regulators and lawmakers, often specify that genetic engineering refers only to modifications made by recombinant DNA technology, but I prefer the more broad usage. Genetic engineering is, as the name implies, the engineering of genetic material in living cells.
There are two processes which, I believe, are mistakenly called genetic engineering: artificial selection (aka selective breeding) and PGD (pre-implantation genetic diagnosis, also known as embryo screening). Artificial selection refers to selective breeding of organisms with the desired traits (and, it is hoped, the desired genes) in order to breed more organisms with the desired traits. Pre-implantation genetic diagnosis is the term for determining the genetic makeup of human embryos before they are implanted for IVF, and usually implies choosing to implant the healthiest or more desirable of embryos.
These are both selective processes, and are often likened to genetic engineering, but often for different reasons. Selective breeding is often considered to be genetic engineering by those defending genetic modification of crops and livestock, as surely the traditional farming methods of the past couldn’t have been wrong (*cough cough*). On the other hand, PGD is often maligned as genetic engineering by those opposed to the idea, as surely genetic engineering of humans is to be vehemently opposed (*cough cough*). In fact, some proponents of human enhancement could even make both leaps at once, claiming that genetic engineering is just like the evolutionary processes of nature (only faster) and therefore that techniques like PGD are likewise just speeding up the natural selection of human embryos that occurs naturally.
But I strongly believe that a selective process is not a form of engineering. In most cases of selection, genomes are not first intentionally modified by human actions. Instead, modifications happen mostly randomly due to mutations and the natural forms of genetic recombination that occur during reproduction. This provides the variety on which breeders, farmers and parents/reproductive specialists can act to select which will be kept and which will be discarded. So, while these selective processes are intentional modifications of the proportions of certain genetic material in a population, they do not entail any intentional modification the genetic material of any individual organism. Selection is no more an act of genetic engineering than going shopping is an act of manufacturing.
Further, I’d be inclined to argue that cloning is also not a form of genetic engineering, as the genetic material is replicated intact rather than modified. Cloning is really just a very effective form of selective breeding, where every piece of genetic material within a particular cell is replicated in the cloned organism. Cloning, therefore, is no more an act of genetic engineering than using copy+paste is an act of writing.
All of this is really just semantics and word games, because it doesn’t really affect the ethical discussions on these issues. Equivocation is avoided, certainly, but appeals to the past, appeals to tradition, slippery slope arguments or arguments rooted in repugnance are also dubious moral arguments. Every new technology will have consequences, some similar to those seen in other technologies and some completely novel. Each technology should be evaluated individually, with comparisons used only when necessary and not stretched beyond reasonable limits.