By Aliza Rochwarger, Staff Writer
Can an animal that went extinct thousands of years ago be brought back into existence? Is it really possible to recreate ancient genetic material? Are we living in a sci-fi fantasy inspired by Jurassic Park?
De-extinction is the process of “resurrecting” extinct species by replicating the genes that made them unique. Although the extinct animal is not being literally resuscitated, by cloning or genetically engineering modern relatives, scientists may be able to resurrect the traits the species once had. The many scientific innovations, such as the CRISPR/Cas9 gene editing system, allow researchers to continuously explore the boundaries of genetic engineering and advance the scientific understanding of genetic factors that could enable adaptation to cold climates and woolly hair growth. This research could have a significant impact on de-extinction efforts and increase conservation efforts on endangered animals.
In a recent experiment done by the company Colossal Biosciences, researchers identified the genetic traits that helped the species survive in harsh Arctic environments and inserted these unique genes into mice. Although the most closely related species is the Asian elephant, scientists chose to perform this experiment on mice due to ethical concerns related to experimenting on an endangered species. Mice also have smaller genomes and shorter lifespans, making them a more manageable initial test subject. Performing the genetic modifications on smaller animals with a shorter gestation period also combats the practical and scientific challenges of bringing back an entire wooly mammoth in one go.
Even with advances in genetic editing, the process of resurrecting an extinct animal is extremely difficult and requires recreating the entire biology of a species, including its behavior, ecology and potential interactions with the modern ecosystem. In order to ultimately recreate the wooly mammoth, the genome of an Asian elephant must be edited, bringing with it additional challenges, like the larger anatomy, biology and distinct behaviors.
The researchers used a cutting-edge method to edit up to seven genes simultaneously, targeting genes linked to hair morphology and lipid metabolism. Key modifications included mutations in genes like Fgf5, Tgm3, Fam83g and Fabp2 which are involved in the hair phenotype and the susceptibility to the fatty liver condition. This resulted in a group of genetically modified mice with traits such as long, curly coats with lighter colored fur.
Critics argue that we may be “playing G-d” by bringing back a species from extinction, and the need to proceed cautiously when editing a genome is clear. Questions must be asked regarding the ethical issues of choosing which species to revive and how it might affect the greater ecosystem, as well as biodiversity. Critics also wonder whether de-extinction is safe for the animals being tested on, let alone for the environment and the greater world. A species that has been extinct for thousands of years may be better off remaining in the past, as reintroducing it to today’s ecosystem can have many unforeseen consequences. While it may seem like all fun and games to create new species and alter the already existing ones, there are many potential risks and dangers involved that must be carefully considered.
De-extinction is a promising field of study, with its successes bringing even more scientific knowledge to the world, like an understanding of the genetic basis for traits like cold tolerance and woolly fur, as well as the possible resurrection of unique animals that even non-science lovers will find interesting. Yet, while these lab-grown mice may carry mammoth genes, they are still fundamentally mice. This calls into question whether we are truly reviving a lost species or just creating new organisms with characteristics inspired by those of the past. The distinction between a real woolly mammoth and a woolly mammoth mouse is drastic; although these mice have been altered to carry DNA that wooly mammoths likely had, there are still core differences between the two species.
The successful resurrection of woolly mammoths would mark a major breakthrough in genetic research and have significant ecological implications, such as the possibility for endangered species to be saved and for the genomes of certain animals to be altered in order to create more genetic diversity. This would expand the possibilities of what can be accomplished using the genetic tools scientists have recently developed. While the ability to modify genomes once seemed impossible, it can now be done, raising questions about what more can be accomplished with these same tools and discoveries.