The real ethical issue is that you're giving "performance enhancers" to babies. We can't test this stuff in vitro or in adults, not really. So any baby born thi

The real ethical issue is that you're giving "performance enhancers" to babies. We can't test this stuff in vitro or in adults, not really. So any baby born this way is, in some sense, an experiment. And crucially, so are all of those babies' children and their children, because they will inherit some or all of the genetic changes.