Scientists in China have identified a genetic switch that can restore the ability of mammals to regenerate tissue, potentially revolutionizing regenerative medicine. This discovery, published in the journal *Science* on June 27, 2025, offers hope for treating organ damage and traumatic injuries.
Mammals, unlike some animals like fish and salamanders, have limited regenerative abilities. The ear pinna, or outer ear, serves as a good model for studying this, as its regenerative capacity varies across different mammal species. This research could unlock the secrets of how our bodies can heal themselves.
The study found that the gene *Aldh1a2* is crucial for regeneration. Non-regenerative mammals don't activate this gene sufficiently after injury, leading to a lack of retinoic acid (RA), a molecule essential for tissue repair. Researchers from the National Institute of Biological Sciences (NIBS), BGI Research, and Northwest A&F University were involved in this research.
By either supplying RA externally or activating *Aldh1a2* using a gene enhancer from rabbits, the scientists successfully restored regenerative capacity in mice and rats. This breakthrough highlights a key target in the evolution of regeneration and provides a framework for understanding why other organs or species fail to regenerate. This discovery could lead to new treatments for human injuries and diseases.