Anyone who has ever observed a lizard must not have failed to notice that they are capable of detaching their tails, and then regenerating them from scratch. This propensity for “spontaneous regeneration” is something that few organisms possess, and mammals are sadly not one of them. But thanks to a team of Arizona State University scientists, the genetic recipe behind this ability has finally been unlocked.
This breakthrough is a small part of a growing field of biomedicine that seeks to improve human health by tampering with the basic components (i.e. our DNA). The research, which was funded by grants from the National Institutes of Health and Arizona Biomedical Research Commission, also involved scientists from the University of Arizona College of Medicine, Translational Genomic Research Institute, and Michigan State University.
According to Prof. Kenro Kusumi, lead author of a paper on the genetic study, lizards are the most closely-related animals to humans that can regenerate entire appendages. They also share the same genetic language as us, so it’s theoretically possible that we could do what they do, if only we knew which genes to use and in what amounts. As Kusumi explains in the paper, which was published Aug. 20 in the journal PLOS ONE. :
Lizards basically share the same toolbox of genes as humans. We discovered that they turn on at least 326 genes in specific regions of the regenerating tail, including genes involved in embryonic development, response to hormonal signals, and wound healing.
Other animals, such as salamanders, frog tadpoles, and fish, can also regenerate their tails. During tail regeneration, they all turn on genes in what is called the ‘Wnt pathway’ — a process that is required to control stem cells in many organs such as the brain, hair follicles and blood vessel. However, lizards have a unique pattern of tissue growth that is distributed throughout the tail.
It takes lizards more than 60 days to regenerate a functional tail — forming a complex regenerating structure with cells growing into different tissues at a number of sites along the tail. According to Katsumi, harnessing this would be a boon for medicine for obvious reasons:
Using next-generation technologies to sequence all the genes expressed during regeneration, we have unlocked the mystery of what genes are needed to regrow the lizard tail. By following the genetic recipe for regeneration that is found in lizards, and then harnessing those same genes in human cells, it may be possible to regrow new cartilage, muscle or even spinal cord in the future.
The researchers also hope their findings will also help repairing birth defects and treating diseases such as arthritis. Given time, and enough positive results, I think it would be fair to expect that Google’s Clinical Immortality subsidiary – known as Calico – will buy up all the necessary rights. Then, it shouldn’t be more than a decade before a gene treatments is produced that will allow for spontaneous regeneration and the elimination of degenerative diseases.
The age of post-mortal is looming people. Be scared/enthused!