Scientists studying axolotls, zebrafish, and mice have uncovered a shared set of genes that may one day help humans regrow lost limbs. By identifying powerful “SP genes” involved in regeneration, researchers discovered that disabling these genes stopped proper bone regrowth in salamanders and mice. They then used a gene therapy inspired by zebrafish biology to partially restore regeneration in mice, marking a major step toward future treatments that could replace damaged limbs with living tissue instead of prosthetics.
Axolotls are famous for their extraordinary ability to regrow entire limbs along with tails, spinal cord tissue, and parts of organs including the heart, brain, lungs, liver, and jaw.
Woah, that’s a lot of regeneration.
Mice can regenerate the tips of their digits, and humans can sometimes regrow fingertips if the nailbed remains intact after injury, allowing skin, flesh, and bone to regenerate.
TIL.
Unwritten here is how exactly they go about snipping mouse fingers and axolotl tails off. I hope there’s at least anesthetic involved.
In mice, the treatment encouraged bone regrowth in damaged digits and partially restored some regenerative abilities lost when the SP genes were absent.
So, sounds like small steps towards identifying part of the puzzle. Cool discovery, but plenty still to do before we’re regrowing mouse arms much less human arms.
Woah, that’s a lot of regeneration.
TIL.
Unwritten here is how exactly they go about snipping mouse fingers and axolotl tails off. I hope there’s at least anesthetic involved.
So, sounds like small steps towards identifying part of the puzzle. Cool discovery, but plenty still to do before we’re regrowing mouse arms much less human arms.
The process is established and described e.g. here: https://www.nature.com/articles/s41536-025-00441-y
The original study is over 50 years old and was focussed on children: https://www.docdroid.net/LYIhrKu/1972-child-fingertip-regeneration-pdf