De-extinction of Dire wolves: Colossal Biosciences, a biotechnology company in Texas, recently announced that it had “resurrected” a dire wolf, a large predator that went extinct more than 12,000 years ago.

• About Dire Wolves: The genome of a gray wolf (Canis lupus) has 2.447 billion base pairs.

o Similarity: Gray wolf and dire wolf (Aenocyon dirus) genomes are 99.94% identical, i.e., 2.445 billion base pairs are the same.

o Difference: The remaining 0.06% (or 1.47 million base pairs) makes the two animals genetically distinct.

o Comparison: Humans and chimpanzees share 98.77% DNA, yet are very different — highlighting that small genetic differences are significant.

o Colossal's approach: Scientists edited the gray wolf genome and implanted embryos into surrogate dog mothers.

o Genetic edits: Edits were made at 20 loci across 14 genes to “recreate” the dire wolf.

o Estimate: These edits likely represent only 0.02% of the total genetic differences, indicating the pups are not true dire wolves.

• Changes Made by Scientists: Edited genes relate mostly to cosmetic traits like fur colour, density, and body size.

o LCORL gene: One of the edited genes is LCORL, linked to larger size in dire wolves.

o Result: Colossal Biosciences has created gray wolves that look like dire wolves, rather than true dire wolves.