A child died in a Shanghai base-editing trial, undisclosed for a year

Retraction Watch, in a joint investigation with Science, reported on 23 July 2026 that a 6-year-old girl died about a week after receiving an experimental base-editing therapy at Xinhua Hospital, affiliated with Shanghai Jiao Tong University School of Medicine. She was treated in late March 2025. The therapy came from the laboratory of neuroscientist Zilong Qiu at the university’s Songjiang Research Institute; it was delivered into her spinal fluid by viral vector and was intended to correct a single mutated DNA base — a T where there should have been a C — implicated in her cognitive development. The reported cause of death was a severe immune reaction linked to the therapy. It was not made public for more than a year.

Her family had contributed more than $860,000, drawn from savings and from relatives, toward the work that produced the treatment. Qiu’s team published related preclinical animal studies in Nature in early 2026; according to the investigation, that paper carried no reference to the family or to its financial contribution.

This is a distinct case from the HuidaGene HG302 death disclosed on 5 August 2026. Early August coverage describing “a second child” is counting these two together, not reporting a third.