A Companion to the Philosophy of Technology

2. Identity-affecting Genetic Interventions

I shall call genetic interventions that affect who (in the numerical sense) comes to exist identity-affecting and those that do not identity-preserving (although they will, of course, affect the recipient’s qualitative identity). Both pre-implantation and pre-natal diagnosis may be identity-affecting because they may lead to selective implantation and selective abortion respectively. Likewise, perhaps certain forms of gene therapy would, if performed on a conceptus or embryo, have such massive effects on its – or the resulting child’s – properties that a numerically different child would be caused to exist.

Medical interventions usually aim to benefit their recipients but, setting aside cases of “wrongful life” (see below), identity-affecting genetic interventions will often not achieve this. For instance, a fertilized egg that is not implanted because it has the gene for cystic fibrosis or a fetus that is aborted because it has the gene for Huntington’s chorea will not benefit from these procedures. But things may be different if, e.g., a fertilized egg is implanted after a diagnosis reveals that it is healthy.

Some will object to certain genetic interventions because they involve the killing of a fetus (fertilized egg, embryo). Others will argue that such beings have no moral standing and that killing them can be justified on the basis of the interests of the parents (and perhaps societal interests as well).

But, even if we concede ...