GoKawiilBase editing achieves near-complete PCSK9 correction in human embryos, but risks remain
Researchers delivered the ABE8e-V106W base editor as a protein into fertilized human embryos and successfully edited all copies of the PCSK9 gene without producing insertions or deletions, allowing embryos to develop to the blastocyst stage and yielding homozygous edited stem cell lines. However, they also observed occasional chromosome breaks, mosaic editing at nearby and off-target sites, and frequent embryo arrest when the editor was delivered as mRNA instead of protein.