Gene therapy offers hope for rare diseases. But the stories don't always have happy endings.

https://www.usatoday.com/story/news/health/2023/04/24/gene-therapy-rare-disease-alissa-feldborg/11665320002/ Gene therapy offers hope for rare diseases. But the stories don't always have happy endings. At 14 months old, Alissa became the first child to receive a full dose of an experimental gene therapy. More than two years later, her parents hope her short life will help others live. Karen Weintraub USA TODAY