The jurist Bartha Knoppers represents humanity in the thorny task of drawing the line between what is acceptable and what is unacceptable. Sometimes, their work is simple. A little more than three years ago, the Chinese scientist He Jiankui surprised the world that they had been born the first three babies genetically modified, with their genome patched together to, supposedly, be immune to the AIDS virus. The intervention, unnecessary and botched, deserved a prison sentence and the almost unanimous contempt of his colleagues. On other occasions, the red lines between what is admissible and what is inadmissible are much more blurred.
