As with Jesse Gelsinger, the 18-year-old whose death during an early U.S. gene therapy trial in 1999 chilled research in the field for nearly a decade, Mei’s story raises questions about whether such risky treatments should be initially tested on patients with nonfatal conditions. “I don’t think these kinds of experiments should stop, but we need to make sure we are appropriately careful about them,” says bioethicist Hank Greely, director of the Center for Law and the Biosciences at Stanford University. “It’s so easy to be blinded by hope—whether it’s hope for your kid, hope for your research, or hope for your company.”

But nowhere did the form explicitly indicate that any of this could end in death, nor did that come up during any conversations with Qiu or the other doctors, Jason and Linda say. “Death should always be mentioned in a first-in-human trial,” says Greely, the bioethicist.