British scientists have used a genome editing tool known as CRISPR/Cas9 to knock out a gene in embryos just a few days old, testing the technique’s ability to decipher key gene functions in early human development. The researchers said their experiments, using a technology that is the subject of fierce international debate because of fears that it could be used to create babies to order, will deepen

understanding of the biology of early human development. CRISPR/Cas9 can enable scientists to find and modify or replace genetic defects. Many describe it as game-changing. “One way to find out what a gene does in the developing embryo is to see what happens when it isn’t working,” said Kathy Niakan, a stem cell scientists who led the research at Britain’s Francis Crick Institute. READ MORE