Why in the News?

A US biotech company, Colossal Biosciences, claims to have genetically engineered three grey wolf pups to carry traits of the extinct dire wolf, calling it world's first successful functional de-extinction. 

What is Functional De-extinction?

• Unlike true de-extinction, where a species is brought back exactly as it existed, functional de-extinction focuses on reviving ecological roles and traits of extinct species using gene editing and cloning techniques.
• These revived organisms are not exact replicas, but are genetically engineered to closely resemble extinct species in form or function.
• It typically involves advanced techniques like CRISPR gene editing, cloning, and genome mapping.

About Dire Wolf Dire wolves (Aenocyon dirus): They were large canines that dominated southern Canada and US before they went extinct about 13,000 years ago.  Physical Characteristics:  Up to 3.5 feet tall, over 6 feet in length, weighing ~68 kg. Comparison with Grey Wolf: Dire Wolves resembled the gray wolves (Canis lupus) of today, but were larger, with white coats, wider head, larger teeth, more powerful shoulders & muscular legs etc. Causes of extinction: Possibly linked to the disappearance of large prey species and human activities.

How Colossal Biosciences brought Back the Dire Wolf?

They used both cloning and gene-editing based on 2 ancient samples of dire wolf DNA to birth three pups.

• Ancient DNA Extraction: Extracted DNA from two dire wolf fossils - a 13,000-year-old tooth from Ohio and a 72,000-year-old ear bone from Idaho. 
• Genome Mapping: Sequenced the dire wolf genome and compared it with modern gray wolves to identify functional genes. 
• CRISPR Gene Editing: The genes of the dire wolf's closest living relative, the gray wolf, were edited to include gene variants specific to the formerly extinct animal. 
• Cloning & Birth: Edited DNA was implanted into enucleated ova, which were carried by domestic dog surrogates, leading to the birth of the three pups named Romulus, Remus, and Khaleesi.
  • Instead of traditional cloning, scientists used a less invasive method involving endothelial progenitor cells (EPCs) from gray wolves, the dire wolf's closest living relatives. 

Concerns about Functional De-extinction

• Ecological Disruption: The "de-extinct" species might not perfectly replicate the extinct species' role, potentially becoming invasive, disrupting existing ecological balances.
  • These are genetic approximations, not actual revivals of extinct species.
• Ethical Considerations: Concerns exist about the welfare of the animals created through de-extinction, especially if the process involves significant genetic manipulation or if the animal is ill-suited to the current environment.
• Resource Diversion: Critics argue that the significant resources required for de-extinction projects could be better spent on conserving existing endangered species and their habitats, which are facing immediate threats. 
• Lack of Regulation: No clear global ethical or legal frameworks for de-extinction.

Conclusion

The revival of dire wolf-like creatures by Colossal Biosciences represents a groundbreaking step in de-extinction science. While it opens new avenues for conservation and understanding extinct species, it also necessitates careful consideration of ethical, ecological, and scientific implications. As technology advances, the balance between innovation and responsibility becomes ever more crucial.