1. Colossal Bioscience

On March 4, Time Magazine covered the company’s groundbreaking achievement: using gene editing tools, Colossal managed to breed “woolly mice” with woolly mammoth characteristics, specifically long, thick coats of fur and accelerated fat metabolism.

Scientists were able to reconstruct the woolly mammoth genome by harvesting DNA from multiple samples taken from Alaska and Siberia. They then compared the genome to that of the Asian elephant, the closest living relative of woolly mammoths, to identify the specific genetic differences that made mammoths unique.

Researchers then used CRISPR-Cas9 to make specific changes to the genome of mouse embryos, giving them traits similar to those of the woolly mammoth. The result was the world’s first “woolly mice”.

“The Colossal woolly mouse marks a watershed moment in our de-extinction mission,” said company CEO Ben Lamm in a 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.”

The company’s CEO, Ben Lamm, says the ecological effects caused by the threat of extinction will eventually lead to economic impacts, citing an estimate from the World Economic Forum that predicts biodiversity loss could cause the global GDP to lose US$2.7 trillion annually by 2030.

In a 2022 interview with Christine Lagorio-Chafkin for the What I Know podcast, Lamm explained that a higher population of large herbivores could reduce ground surface temperatures, decelerating the thaw of arctic permafrost that some studies project will release between 119.3 and 251.6 billion tons of carbon by 2100.

To support its goals, the company raised US$200 million in January from TWG Global in a Series C funding round, bringing its total cash raised to US$435 million and its total valuation to US$10.2 billion.

The company is also researching ways to resurrect the Tasmanian tiger and the dodo bird.

2. Loyal

On February 26, the US Food and Drug Administration (FDA) accepted the Reasonable Expectation of Effectiveness section of Loyal's conditional approval application for LOY-002, a daily tablet developed by the company to extend the lifespan for dogs aged 10 and older weighing at least 14 pounds. The pill targets metabolic dysfunction and provides an alternative to caloric restriction and other established longevity interventions.

In a May 2022 interview published in Authority Magazine, Celine Halioua, the company’s CEO, explained the objective of a cross-sectional epigenetic study, X-Thousand Dogs. “In addition to sequencing a dog’s DNA, the X-Thousand Dogs study is looking for changes in the structure of the DNA itself," she explained at the time. “By identifying and tracking these changes, Loyal can create a snapshot into what is happening with a dog’s health.”

Halioua said she hopes that Loyal’s research will have future human applications. “The company’s thesis is that research and therapeutics for extending healthspan and lifespan for dogs will lead to further understanding of aging in humans.”

To support its submission to the FDA, the company is currently running the STAY study, a four year, double-blind placebo clinical trial that began in December 2023. Loyal also recently secured US$22 million in a Series B-2 funding round led by Valor Equity Partners, a private equity firm that has also invested in SpaceX, Neuralink, Anduril and The Boring Company.

4. eGenesis

eGenesis is also making significant progress in xenotransplantation through its collaborations with Massachusetts General Hospital (MGH). In March 2024, surgeons at MGH successfully transplanted a genetically engineered pig kidney into a living human patient in a procedure authorized by the FDA under the Expanded Access pathway.

eGenesis then received US$191 million in September 2024 to advance its kidney, code-named EGEN-2784, to in-human studies. In a statement emailed to Nature, the company said it received FDA approval to conduct three pig kidney transplants under compassionate use in December 2024.

A second patient — the first in this study — with end-stage renal disease received the operation on January 25 of this year. The patient was discharged in good health a week after the surgery and is no longer receiving dialysis.

Beyond its pig kidney research, eGenesis has also begun collaborating with OrganOx, a commercial-stage organ technology company spun out of the University of Oxford in 2008. Their work involves developing a liver support system that uses genetically modified pig livers in OrganOx's metra device, a normothermic machine perfusion system, to temporarily perform liver functions for patients with acute liver failure.