Six-Year-Old Died After Experimental Brain Gene-Editing Trial in Shanghai, Investigation Finds Safety Warnings Were Ignored

A 6-year-old girl identified by the pseudonym Mei died in March 2025, seven days after entering Xinhua Hospital in Shanghai for an experimental gene-editing treatment aimed at her developmental disability, according to a joint investigation by Science and Retraction Watch.

Mei suffered from a genetic mutation affecting her cognitive development. Doctors under neuroscientist Qiu Zilong of Shanghai Jiao Tong University administered a base-editing therapy, a more precise cousin of CRISPR, designed to correct the mutation in her nervous system. The treatment was delivered via an injection of what Science described as trillions of adeno-associated viruses carrying the gene editor directly into her spinal fluid. It reportedly cost her family more than $860,000.

She was, according to the investigation, the first human being to undergo gene-editing therapy targeting the brain. She died from thrombotic microangiopathy, a severe blood-clotting disorder triggered by an immune reaction to the high viral dose, according to MedPage Today's account of the case.

The investigation found the hospital used an expedited internal approval process that bypassed standard national regulatory review. Reporters also found that Qiu and his team understated the risks of the procedure when informing Mei's parents, and that international experts who reviewed the record afterward said adverse reactions seen in earlier animal studies should have stopped the trial from moving to human subjects.

Mei's death was not the only case. A separate, unrelated gene-editing trial in China involving a child with Duchenne muscular dystrophy went unreported for nearly a year after the child died of respiratory distress following a severe immune response to viral-vector gene therapy, according to MedPage Today.

What happened after Mei died

According to Science's reporting, the hospital paid what the investigation called a modest fine to a local health authority. Qiu faced no public sanction until the Science and Retraction Watch investigation surfaced this year. Qiu Zilong is now under investigation following publication of the findings, according to Breitbart's account of the story.

Reporters also found that Qiu's team published a paper on the underlying animal research in the journal Nature this year, without disclosing the human child's death or the financial contribution her family made toward the project. Mei's parents came forward, using pseudonyms, because they were angry at what they saw as a lack of accountability. One parent said learning the extent of the missing safeguards changed how the family views the entire project.

Gene editing in context

Gene-editing therapy is a real and rapidly advancing field, not a fringe experiment. In 2023 the FDA approved exagamglogene autotemcel, sold as Casgevy, as the first gene-editing therapy for sickle cell disease. More recently, an infant known as Baby KJ received a custom base-editing treatment for a rare metabolic disease and has continued to do well after three doses, according to MedPage Today.

But the risks are real too. CRISPR and base-editing systems can produce unintended off-target edits, and viral delivery systems, while effective at getting the gene editor into cells, can trigger dangerous immune responses. MedPage Today notes that base editing reduces but does not eliminate off-target activity, and that both thrombotic microangiopathy and fatal immune reactions have now been documented in Chinese pediatric gene-editing trials.

Where the coverage diverges

Breitbart's account frames the story primarily as a case of Chinese Communist Party cover-up and an effort by Beijing to out-compete the United States in biotech, calling the secrecy surrounding Mei's death part of an "arrogant" and "hideous" pattern of concealment. MedPage Today's account treats the case more as a cautionary tale about the ethics of first-in-human trials generally, drawing a direct line back to 1970s bioethics debates about how parental desperation and scientific optimism can push risky treatments forward faster than caution should allow.

Both accounts agree on the documented facts: the fast-tracked approval, the understated risk disclosure, the animal-study warning signs, the modest fine, and the year-long delay in reporting a separate fatal case. Neither source reports that Chinese regulators have announced formal charges against Qiu or the hospital, only that Qiu is now under investigation.

What specific findings that investigation will produce remains unclear, as does whether Xinhua Hospital or Shanghai Jiao Tong University will face further regulatory consequence, and whether China's health authorities will change the expedited-approval pathway that let this trial bypass standard national review in the first place.