UK scientists are experimenting on seven-day old humans to learn how to "edit" DNA before killing them and discarding them.
A team from the Francis Crick Institute is using "excess" living human embryos for their experiments who were frozen for in-vitro fertilization (IVF). They then "edit" the human DNA by taking out a vital gene from "healthy, normal" embryos.
States the BBC:
Breakthroughs in manipulating DNA have allowed the team at the Crick to turn off a gene – a genetic instruction – suspected to be of vital importance. The easiest way of working out how something works is to remove it and see what happens. So the researchers used the gene-editing tool Crispr-Cas9 to scour the billions of letters of genetic code, find their genetic target and break the DNA to effectively disable it.