Abstract

The development of the genome editing system called CRISPR–Cas9 has opened a huge debate on the possibility of modifying the human germline. But the types of changes that could and/or ought to be made have not been discussed. To cast some light on this debate, I will describe the story of the CRISPR–Cas9 system. Then, I will briefly review the projects for modification of the human species that were discussed by biologists throughout the twentieth century. Lastly, I will show that for plenty of reasons, both scientific and societal, germline modification is no longer a priority for our societies.