There are many various species that have genes that can enable the healing or even the regrowth of missing limbs. If humans looked back on the evolutionary tree of life back to the roots, you would see that we share a common ancestor that possess regenerative properties for lost body parts. Humans lost this special power through the course of millions of years of evolution. Two species that still possess this property are salamanders and zebrafish. Researchers have been studying these species and making a list of all the genes that allows animals to regenerate a tail or repair damaged tissue. They have discovered that humans have counterparts to these genes and they believe that the genes themselves may not be the key to the regeneration process, but in the sequences that activate these genes when an injury occurs. A study at Duke University discovered that “tissue regeneration enhancer elements”, called TREEs, are sequences that activate genes at the site of injuries. Researchers have found many genes in various animals that promote regeneration. One in particular is a molecule called neuregulin 1. This molecule has been found to help repair and regenerate heart muscle cells and even regenerate a missing fin. Dr. Kenneth Poss of Duke University School of Medicine has led studies specifically trying to see what activates these genes, what keeps them running while the regeneration process is being undergone, and what deactivates them when the process is complete.
The first thing they looked for in their research was the genes in zebrafish that allows them to regenerate a fin or heart cells. They found a gene called leptin b that controls those processes in these fish. The sequence of leptin b was surrounded by roughly 150,000 base pairs at around 7,000 base pairs away, an enhancer element was found. This enhancer was cut down to its bare minimum required to function properly. They found that the element could be separated into two parts, one for heart repair and the other for repairing a fin. They took these two sequences and fused them to fibroblast growth factor and neuregulin 1. What they saw was that zebrafish had superior regenerative responses to injury. Lastly they tested to see if these TREEs could be effective in mammals. They tested mice. They found evidence that shows that there is a definite possibility for mammals to possess regenerative properties for damaged tissues or maybe even repair and regrow a missing limb.
Regeneration is a really interesting ability. It is amazing that some species possess the ability to regrow a fin or body part after an injury. I think research should be continued on regeneration. In particular, research should be done to see if it is possible for people to possess this ability. It would be amazing if one-day humans could be able to regrow a limb. There are many tragedies that happen throughout the world such as car accidents, shark attacks, war injuries, etc. and it would be great if we could uncover the mysteries behind regeneration so that people can repair their own injuries.