With a second delayed report of a child's death in China, criticism is rising of a looser form of clinical trial. One expert: what "bothers me is the lack of transparency.'

"A cutting-edge gene-editing trial in China went disastrously wrong. A family wants accountability."

With a second delayed report of a child's death in China, criticism is rising of a looser form of clinical trial. One expert: what "bothers me is the lack of transparency.'