Ability of making distinctions between various types of genetic interventions

One further issues needs to be addressed with respect to the ability of making distinctions between various types of genetic interventions, in particular those that relate to the enhancement of complex traits such as intelligence. This is that any attempts to make distinctions between the appropriateness of different interventions is a flawed process because with respect to complex traits in particular it is difficult if not impossible to through the manipulation of a person genetic code make any real changes to these complex traits with any degree of certainty. This is because with traits such as intelligence, it is not the case that the level of a person intelligence is controlled either by the genes of the person in question or by their environment, rather these complex traits are instead the result of the both the actions of the gene and the environment as well as a random developmental noise. This is “in contrast to models of development in which genes or environments are determinative.”[xii] This idea suggests that it is therefore difficult if not impossible to manifest any real directed change in a complex trait via genetic intervention and that as a result procedures aimed at enhancing these complex traits are inappropriate.