HONG KONG (AP) — A prominent American scientist is warning against a backlash to the claim that a Chinese scientist has helped make the world's first gene-edited babies.

Harvard Medical School dean Dr. George Daley says it would be unfortunate if a misstep with a first case led scientists and regulators to reject the good that could come from altering DNA to treat or prevent diseases.

Daley spoke Wednesday at an international conference in Hong Kong, where the Chinese scientist, He Jiankui (HEH JEE-ahn-qway) of Shenzhen, also is scheduled to speak.

He says he altered the DNA of twin girls when...