Girl, 6, dies after receiving world's first base-editing therapy to the brain in China

Published Jul 26, 10:23 AM UTC

A six-year-old girl in China died in March 2025 after receiving what researchers believed was the world's first base-editing therapy directed at the brain, according to an investigation by Science and Retraction Watch. The girl had Snijders Blok-Campeau syndrome, a rare neurodevelopmental disorder. Researchers led by neuroscientist Zilong Qiu at Shanghai Jiao Tong University developed a personalized base-editing therapy to correct the genetic mutation in her brain cells. The treatment required injecting large doses of adeno-associated viruses (AAVs), which carry risks of severe immune reactions. The girl's parents contributed approximately $860,000 to fund the therapy's development. Toxicology studies in monkeys had found liver injury and kidney damage, but researchers proceeded anyway. The girl developed fever and kidney damage within days of the injection and died a week later. The case has prompted debate about oversight of 'first in human' gene-editing trials, particularly for rare but serious disorders, and highlighted gaps between China's regulations and their enforcement.