Regenerative Proteins identified in Newts are Not Found in Humans.

            A recent study on newts has shown discouragement in the possibility for the regrowth of human limbs. In late February of this year, Zoe Cormier and Nature Magazine published an article on Scientific American titled, “Newt Finding Might Set Back Efforts to Regrow Human Limbs.”  It has been discovered that Notophthalmus viridescens (the red spotted newt) can regenerate lost tissue in the heart, central nervous system, and also the lens of its eye.  

Doctors and scientists questioned whether or not this phenomenon is due to genetics common to all animals. Unfortunately, Thomas Braun of the Max Planck Institute for Heart and Lung Research in Germany suggests that the repair mechanism may be limited to certain organisms. Since newts have a genome much larger than that of humans (mice and flies, too), comparative analyses was done using the newts’ RNA in gene expression (transcriptome), focusing both the primary and regenerated tissue in the heart, limbs, and eyes of embryos and larvae. The researchers found that about 15,000 of the 120,000 RNA transcripts codes for proteins, 826 of which are found only in the newt. Furthermore, several of the RNA transcripts were expressed at different levels in the regenerated tissue than in the primary tissue.  

 From these results, scientists, such as Elly Tanaka from the Center of Regenerative Therapies in Germany, believe that newts have species-specific adaptations responsible for their regeneration capabilities. Tanaka subsequently recommends that researchers focus more on improving scar healing and increasing the speed of organ regeneration, which are more plausible than the regrowth of human limbs.

The topic of regenerating limbs is a possible solution to the use of prosthetics for replacing limbs. In her chapter, “Pin the Tail on the Dolphin (122),” Emily Anthes discusses the implications of using manufactured appendages on animal bodies. A team of scientists designed and manufactured a prosthetic tail for Winter, a dolphin who lost her tail. However, Winter was not set out back in the ocean because fear of her survival with the man-made tail.  This prosthetic was not guaranteed to last the rest of her life in the wild and it was unknown whether long-term physical and psychological discomfort would play a role in her new life.

In response to this new study, Anthes would argue that the information found in the newts should be used to pursue possible regeneration of limbs in other organisms. She believes that biotechnology has provided us an obligation to animals and that we should use our knowledge to improve the lives of all beings so we can all evolve together (181). If the information gained from this study is thrown out because it has no use to further humanity, then this is an example of an ethical quagmire. There is an underlying moral obligation to help other species because of our use of animals as tools in medical research. Having this knowledge could greatly impact how we can help other animals. If scientists can identify what genes express the regenerative property in other species, they can potentially find a way to use this to aid other animals. Maybe future Winters can be helped with regeneration of their limbs and then be released back into the wild, where they belong, instead of being aided and then needing to be under human care for the rest of their lives.

References:

Anthes, E. (2013). Frankenstein’s Cat: Cuddling up to biotech’s brave new beasts.

New York: Scientific American.

Cormier, Z., & Nature Magazine. (2013). Newt Finding Might Set Back Efforts to

Regrow Human Limbs.  Scientific American. Retrieved from
http://www.scientificamerican.com/article.cfm?id=newt-finding-might-set-back-efforts-to-regrow-human-limbs