Genetically altered mouse to pave way for resurrection of wolly mammoth?

The birth of the Colossal Woolly Mouse, announced by the US-based Colossal Biosciences on Tuesday may seem like a small step in genetic engineering.

What it is actually, is a giant leap in the journey to resurrect the woolly mammoth.

For the Colossal Woolly Mouse are mice engineered to express multiple key mammoth-like traits that provide adaptations to life in cold climates.

“By successfully modifying seven genes simultaneously, Colossal’s team created mice with dramatically altered coat color, texture, and thickness reminiscent of the woolly mammoth’s core phenotypes,” said the company in a statement.

This achievement, it added, demonstrates the feasibility of expressing traits using information learned from the computational analysis of 59 woolly, Columbian, and steppe mammoth genomes ranging from 3,500 to over 1,200,000 years old confirming these pathways as the crucial targets for mammoth de-extinction.

“The Colossal Woolly Mouse marks a watershed moment in our de-extinction mission,” said Ben Lamm, Co-Founder and CEO of Colossal Biosciences, in the statement. “By engineering multiple cold-tolerant traits from mammoth evolutionary pathways into a living model species, we’ve proven our ability to recreate complex genetic combinations that took nature millions of years to create. This success brings us a step closer to our goal of bringing back the woolly mammoth.”

As part of their research, Colossal’s team explored a data set of 121 mammoth and elephant genomes, including Colossal-created high quality reference genomes for Asian and African elephants, to identify significant genes that impact hair and other cold-adaptation traits. The team focused on a suite of genes that made mammoths different from their closely related Asian elephant cousins, said the company. The list was refined to include 10 genes related to hair length, thickness, texture, and colour as well as lipid metabolism that were compatible with expression in a mouse.

The team then edited the mouse genome to modify seven genes.

“The Colossal Woolly Mouse showcases our ability to use the latest genome editing tools and approaches to drive predictable phenotypes,” said Dr Beth Shapiro, chief science officer, Colossal. “It is an important step toward validating our approach to resurrecting traits that have been lost to extinction and that our goal is to restore.”

The implications of this breakthrough extend beyond the laboratory, Lamm added.

Not only is the Colossal Woolly Mouse the first living animal engineered to express multiple cold-adapted traits using mammoth genes , it is also a living model for studying cold-climate adaptations in mammals.

“The success of the research shows that we can succeed in the complete process, from comparative genomics to gene selection to multiplex gene editing, and end up with healthy animals that display multiple phenotypes that we deliberately engineer. It proves that our process and pipeline for de-extinction works.”