Doctors link infant's brain tumor to gene therapy virus in rare case

Doctors treated 13-month-old Adam with an experimental gene therapy after his stem cell transplant failed, and the boy subsequently reached developmental milestones such as learning sign language and reading.

A routine scan later revealed a golf‑ball sized tumor in his brain. Physicians examined the case and concluded that the tumor was associated with the viral vectors used in the gene therapy, marking a rare documented link.

Medical experts caution that while such adverse events are extremely uncommon, they must be balanced against the profound benefits gene therapies can provide for patients with life‑threatening rare diseases.