CAMBRIDGE, Mass.—When a Chinese scientist last month claimed to have created the first gene-edited babies, scientists around the world were stunned and alarmed, saying the research had been done without proper disclosure or oversight.
Now, scientists who examined the very limited available data from the experiments are questioning whether the gene edits the scientist claimed he made were even successful. One prominent scientist has called for a moratorium on genetically editing human embryos to create a pregnancy until technical,...