As an author of the Nuffield Council on Bioethics’ 2018 report on genome editing and human reproduction, I wonder whether action to regulate editing of the human germ line might be guided by cannabis regulation (see Nature 570, 137; 2019).

In my view, a moratorium on the technology would be regulatory theatre (see E. Lander et al. Nature 567, 165–168; 2019). CRISPR gene editing is cheap and easily accessible, and its practice and products are hard to detect. Like cannabis prohibition, a moratorium risks fostering a black market in unregulated and potentially harmful ‘products’, in this case heritable gene variants.

Might it therefore be safer from a public-health perspective to permit access to licensed human-genome editing that meets acceptable standards? A new committee set up by the World Health Organization (see Nature 567, 444–445; 2019) is already doing important work to set such standards. So, too, is an international commission convened by the UK Royal Society, the US National Academy of Sciences and the US National Academy of Medicine.

As with medical applications of cannabis, legal uses of heritable genome editing would still need ethical approval, and informed public debate must be advanced. Public information campaigns indicating that research into genome editing is at an early stage, and that unapproved experimentation is both risky and illegal, would provide a practical first line of defence against malpractice.

To further ensure responsible governance, legislatures need to advance research on editing human embryos. The UK’s 14-day limit should be extended to permit studies of later-stage human embryos. Research applications should not be impeded by CRISPR exceptionalism, for which there is no legal basis.