In an effort to treat their daughter’s genetic developmental disorder, parents in China paid respected researchers millions in Chinese yuan, a total of $860,000 USD, for a new treatment that had never been used in humans.
But instead of celebrating advances in her writing and language skills, the family is mourning the loss of their only child.
Her treatment went forward even when experts say success was unlikely, animal studies showed red flags for safety, and doctors downplayed risks — including of death, which wasn’t ever mentioned explicitly to the family, a new report in Science says.
Zilong Qiu, who led the research for Mei’s treatment, appeared to be obsessed with publishing research in a prestigious journal, hoping hers would be “the first brain-directed gene-editing therapy.”
Months after her death, he got what he wanted: a paper in Nature, only it doesn’t acknowledge her at all.
The report from Science is making waves in the research world, raising questions about research oversight and capitalizing on desperate families to fund shaky science.
“This shouldn’t have gone to trial,” Steven Gray of the University of Texas Southwestern Medical Center, who develops viruses for gene therapy, told Science. He and other experts are calling for a review of all images and data in the Nature paper published earlier this year by Qiu.
Treating Mei with base editing gene therapy
The family asked to remain anonymous, and asked to refer to their daughter as “Mei.”
Mei had a rare mutation on her CHD3 gene, which plays an important role in early development. Kids like her with Snijders Blok-Campeau Syndrome often have intellectual disabilities and impaired speech and language.
Mei’s teachers told her parents that she was struggling to keep up with other students in writing and language development, but she still had a mild case.
Given that her disorder was not going to get worse over time and was not fatal, it raises questions about why such drastic action was recommended by the experts her parents consulted.
Qiu offered Mei’s family a treatment: base editing, a precise gene editing technique. This technology is still quite new.
Even he admitted in recordings to Mei’s parents that “far fewer people have mastered this technique,” but assured them that he was second only to David Liu, the inventor of base editing.
People have died from gene therapy research, often because the therapy involves injecting a large amount of viruses to deliver genes to cells. This can cause a cascading immune response that can be deadly.
Mei’s case was even more complicated because Qiu’s team was targeting her brain, which is protected by the blood brain barrier.
That means many of the viruses will never reach the target, so the strategy is to deliver “hundreds of trillions of viruses — thousands of times more” than a person getting a virus-based vaccine, like the COVID-19 vaccine, might get.
Promising data, money flows in
Qiu told the parents the therapy was effective in mice — where the blood-brain barrier is easier to cross. Next, he had to prove it was safe in monkeys.
He provided images of monkey brains that showed the therapy reached every region — and “this was welcome proof that the clinical trial should go ahead,” Qiu told the family. But when Science asked experts to review the images, they had concerns.
“It’s completely unconvincing,” said David Sanders, a biochemist at Purdue University who has studied gene therapy. “One can’t have the confidence that one isn’t mostly looking at background staining.”
Then, a month before Mei was treated, all four monkeys that received the therapy developed moderate to severe liver damage. One showed kidney damage — a sign of a well-known reaction to AAV therapy called thrombotic microangiopathy, a deadly pattern of tiny blot clots in the smallest blood vessels in vital organs like the kidney and brain.
Meanwhile, Qiu asked the family to send money to foundations and research organizations, and even some of the research team directly, including a $130,000 payment directly to a researcher overseeing a lab. The parents found this “increasingly troubling,” Science reports.
Mei’s death and questions emerge
In February 2025, the family met with a doctor who told them “the biggest risk for Mei was the possibility that she had antibodies to the viral vector,” Science reported. Otherwise it was “relatively safe.”
In March, she was given the treatment — trillions of viruses were injected directly into her spinal canal to get to her brain.
Within days, she developed a fever that wouldn’t go away. She also wasn’t urinating, indicating her kidneys were affected. She was sent to the ICU. She died a day later.
An emergency meeting of the hospital’s ethics board determined she had died because of the treatment, and her cause of death was thrombotic microangiopathy, the same complication that might’ve affected the monkey.
The hospital was fined about $3,600, and the doctor who told the family it was “relatively safe” was given “verbal counseling.”
The parents asked Qiu to withdraw a paper he’d submitted to Nature about Mei’s case, and he initially agreed, but eventually stopped responding to the family. Nature published Qiu’s research in February without mentioning Mei’s case at all.
Mei’s parents wrote to Nature, who told the parents that the ethical issues they raised “fall outside our purview in terms of data integrity” and that the matter should be handled by the university.
Days after Science‘s report, the university Qiu is affiliated with, Shanghai Jiao Tong University School of Medicine, said it would launch a “comprehensive investigation.” The medical school promised “serious action” based on its findings.
