Claim of CRISPR’d baby girls stuns genome editing summit

HONG KONG — A Chinese scientist’s claim that he used the genome editing technology CRISPR-Cas9 to alter the DNA of human embryos, resulting in the birth a few weeks ago of twin girls, stunned organizers of the Second International Summit on Human Genome Editing, leaving them scrambling to evaluate the claim two days before the scientist is scheduled to speak at the meeting.

“I don’t know the details” of the claim by He Jiankui, said David Baltimore of the California Institute of Technology, chairman of the organizing committee of the summit, which begins on Tuesday in Hong Kong. “We don’t know what will be said” when He speaks at a session on human embryo editing.

The summit’s organizing committee issued a statement Monday saying they had only just learned of He’s research in Shenzhen, China. “Whether the clinical protocols that resulted in the births in China conformed with the guidance” of leading scientific bodies for conducting clinical trials of heritable genome editing “remains to be determined,” the statement said. “We hope that the dialogue at our summit further advances the...