Gene discovery in salamanders brings human limb regeneration closer

Friday 17 April 2026 - 14:50

By: Dakir Madiha

Gene discovery in salamanders brings human limb regeneration closer

Scientists studying regeneration across multiple species have identified a shared genetic program that enables limb regrowth, a breakthrough that could eventually support therapies for regenerating human limbs. By comparing salamanders, zebrafish and mice, researchers uncovered key genes involved in tissue regeneration and used them to develop a gene therapy that partially restored bone regrowth in mouse digits.

The study, published in Proceedings of the National Academy of Sciences, brought together teams working on different model organisms, including the axolotl, zebrafish and mice. Despite their biological differences, regenerating skin in all three species showed activation of two transcription factor genes known as SP6 and SP8. Researchers say this points to a conserved genetic mechanism that drives regeneration across species.

To test the function of these genes, scientists used CRISPR to remove SP8 from the axolotl genome. The result was a failure to properly regenerate limb bones. Similar outcomes were observed when SP6 and SP8 were disabled in mouse digits, confirming that these genes play a critical role in regeneration.

Building on this insight, researchers developed a gene therapy approach using a DNA sequence known as a tissue regeneration enhancer element, or TREE. This element activates genes specifically at injury sites. Scientists engineered a viral vector to deliver FGF8, a signaling molecule linked to SP8 activity, directly to amputation wounds in mice. The treatment partially restored regrowth in genetically impaired mice and accelerated healing in normal ones.

The findings represent a proof of concept that targeted gene therapy could recreate regenerative conditions in mammals that do not naturally regrow limbs. However, the gap between regenerating a mouse fingertip and a full human limb remains substantial. Researchers estimate that more than one million limb amputations occur globally each year due to disease, trauma and infection, underscoring the potential impact of such advances.

Scientists emphasize that future progress will require a multidisciplinary approach combining genetics, bioengineering and clinical research. The study highlights the value of cross species collaboration, showing that insights from organisms like salamanders and fish can inform medical innovation with long term implications for human health.