Researchers at Cincinnati Children’s Hospital Medical Center reported that an AAV-based gene therapy delivering human FMRP to a fragile X mouse model reversed multiple clinically relevant deficits. The work, published in Gene Therapy, used an AAV vector expressing the FMR1 gene and evaluated two delivery routes. The team reported FMRP expression throughout the brain, with intracerebroventricular delivery driving stronger expression in prefrontal areas and intravenous delivery extending expression more broadly. They also reported restoration of symptoms tied to sensory hyperexcitability, adaptation to change, and altered brain activity. The study emphasized clinical translation design choices, including use of an AAV system already reported to perform in humans. The findings add preclinical support for fragile X interventions focused on restoring the missing protein regulator rather than downstream symptom management.