Karolinska Institutet Apr 3 2025 Researchers at Karolinska Institutet have developed a method that shows how the nervous system and sensory organs are formed in an embryo. By labeling stem cells with a genetic 'barcode', they have been able to follow the cells' developmental journey and discover how the inner ear is formed in mice. The discovery, published in Science , could provide important insights for future treatment of hearing loss. Our study shows how different cell types arise from stem