The girl had been diagnosed with global developmental delay in March 2023, her parents told Science. The condition doesn't usually impact life expectancy, University of Montreal geneticist Philippe Campeau, who helped link the condition to the CHD3 gene, told Science. The girl, who died in March 2025 seven days into the world-first clinical gene editing trial, which was aimed at removing her condition, had milder symptoms. Following the girl's death, the scientists returned the funds, and the hospital was fined by local authorities, her parents told Science. The paper only mentioned that research "bridging the gap between preclinical research and clinical translation remains a significant challenge."