Genetic De-extinction

De-extinction, also known as resurrection biology, is a process that reverses plant and animal extinctions by making new varieties of the extinct species. Restoration methods for de-extinction include back-breeding, cloning, and genome editing. The ultimate goal of resurrection biology is to restore the processes that contribute to a thriving ecosystem and to cultivate biodiversity. 

On March 13th, there was a series of live-streamed talks at the TEDxDexExtinction event, which was organized by Revive & Restore and hosted by the National Geographic Society. This event is where the idea of “de-extinction” first gained traction and public interest. Currently, there are eleven books that have been published that contain content on de-extinction. Since the TEDxDexExtinction event, there has also been growing interest in the Woolly Mammoth and Dire Wolf de-extinction projects. 

De-Extinction’s main goal is to help the ecosystem by making it more diverse and introducing species that were once extinct back into the system, to help the processes that make nature thrive. Conservationists put de-extinction as ‘deep ecological enrichment’, or ‘restoring ecosystem functions lost through extinction.’ One project example is to introduce mammoth genes into the Asian Elephant for conservation. This project is done through Colossal, which was founded by George Church, Ph.D, a Harvard and MIT geneticist. 

De-extinction is done through bioengineering skills that essentially manipulate and change the DNA, genomes, or genetic material in the organism. Back-breeding, a restoration method, is done through the ideology of selective breeding. Back-breeding takes ancestral characteristics that are present in species that are alive today. However, back-breeding cannot make living species genetically the same as the extinct species itself; instead, it can make the species resemble it. However, this can lead to the overall health of the species declining. Another method, Cloning, uses intact living cells to genetically make an identical biological life copy. This has been done previously, with a lamb cloned from adult animal cells named Dolly that was born from a female sheep. This process is better for species that are endangered, as it still requires live cells. Finally, genome editing is a restoration method that does not create the exact extinct species, by a mix between a living and extinct organism. Scientists take DNA from an extinct species and put it into the nucleus of a cell, which reproduces and resurrects more species. As mentioned, this cannot create the exact species, but a hybrid of two.  

In April 2025, Colossal Biosciences showcased the birth of three dire wolf pups, which are the first de-extinct animals made through genetic engineering. This was done through first analyzing ancient DNA, highlighting the central genetic traits, and then using a technique called CRISPR Genome Editing. They edited cells from the living gray wolves to carry the genes of the dire wolves. They used CRISPR gene editing on the endothelial progenitor cells that were drawn from the blood of the gray wolves. The cells that were manipulated created embryos that replaced the donor egg cells' genetic material with the “dire wolf” DNA. Finally, the embryos were inserted into dog surrogates that then gave birth to three healthy dire wolves. This method is similar to the de-extinction process of the Woolly Mammoth. 

Currently, De-Extinction is still growing, hitting new milestones, and reaching new heights. While De-Extinction is a promising field with much more to discover, there have been ethical debates that have arisen. This leads to a lot of press articles, videos, and documentaries that cover the pros and cons of De-Extinction. De-Extinction has garnered loads of attention in the past decades, making it a field with a lot of potential! 

References:

Novak, Ben. “De-Extinction.” Genes, vol. 9, no. 11, 13 Nov. 2018, p. 548, https://doi.org/10.3390/genes9110548.

Ord, Sara. “How De-Extinction Works: Methods, Examples and Step-By-Step Process.” Colossal.com, 2022, colossal.com/how-de-extinction-works/.

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