Researchers use CRISPR to edit nonviable human embryos
Illustration created by Stephen Dixon and Feng Zhang
CRISPR (pronounced crisper) burst on the scientific scene in 2012, when researchers transformed what had originally been identified as a rudimentary immune system in bacteria into one of the most powerful tools in molecular biology. Composed of RNA and an enzyme that slices up invading viruses, CRISPR allows researchers to edit nearly any gene in any organism much more precisely and efficiently than older methods.
Many people hope doctors will soon find a way to use the gene editor to fix mutations that cause genetic diseases, a boon for gene therapy. But that potential also comes with big concerns about the possibility of human germline