# Colossal Biosciences

Colossal Biosciences Inc. is an American biotechnology and genetic engineering company working to de-extinct the woolly mammoth, the Tasmanian tiger, the northern white rhinoceros, and the dodo bird. In 2023, it stated that it wants to have woolly mammoth hybrid calves by 2028, and wants to reintroduce them to the Arctic tundra habitat. Likewise, it launched the Tasmanian Thylacine Advisory Committee, a thylacine research project to release Tasmanian tiger joeys back to their original Tasmanian and broader Australian habitat after a period of observation in captivity.
The company develops genetic engineering and reproductive technology for conservation biology. It was founded in 2021 by George Church and Ben Lamm, and is based in Dallas, Texas. As of 2025, Colossal is the highest valued company based in Dallas, Texas at $10.2 billion.

## History
### Foundation

In a 2008 interview with The New York Times, George Church first expressed his interest in engineering a hybrid Asian elephant-mammoth by sequencing the woolly mammoth genome. In 2012, Church was part of a team that pioneered the CRISPR-Cas9 gene editing tool, through which the potential for altering genetic code to engineer the envisioned “mammophant" surfaced. Church presented a talk at the National Geographic Society in 2013, where he mapped out the idea of Colossal.
Church and his genetics team used CRISPR to copy mammoth genes into the genome of an Asian elephant in 2015. That same year, Church's lab integrated mammoth genes into the DNA of elephant skin cells; the lab zeroed in on 60 genes that experiments hypothesized as being important to the distinctive traits of mammoths, such as a high-domed skull, ability to hold oxygen at low temperatures, and fatty tissue. Church's lab reported in 2017 that it had successfully added 45 genes to the genome of an Asian elephant.
In 2019, Ben Lamm, a serial entrepreneur, contacted Church to meet at his lab in Boston. Lamm was intrigued by press reports of Church's de-extinction idea.

### Launch

Colossal was officially launched on September 13, 2021. The launch included a $15 million seed round led by Thomas Tull, Tim Draper, Tony Robbins, Winklevoss Capital Management, Breyer Capital and Richard Garriott. In addition to the de-extinction of the woolly mammoth, Colossal, in partnership with Dr. Paul Ling of Baylor College of Medicine, hopes to synthesize the elephant endotheliotropic herpesvirus, a virus which infects and kills many young Asian elephants.
Colossal also announced that the company's mission was to preserve endangered animals through gene-editing technology and use those same animals to reshape ecosystems to combat biodiversity loss.
The company's genomic modeling software development could potentially bring forth advancements in disease treatment, multiplexed genetic engineering, synthetic biology, and biotechnology. Colossal recruited mammoth and modern elephant experts Michael Hofreiter and Fritz Vollrath, as well as bioethicists R. Alta Charo and S. Matthew Liao for their consultation. Other scientific advisory board members include: Carolyn Bertozzi, Austin Gallagher, Kenneth Lacovara, Helen Hobbs, David Haussler, Elazar Edelman, Joseph DeSimone, Erez Lieberman Aiden, Christopher E. Mason, and Doris Taylor. Colossal’s team includes over 170 scientists and 95 advisors that specialize in fields such as genomics and paleontology.
In October 2021, Colossal announced its partnership with VGP; through this collaboration, Colossal will provide funding for VGP to sequence and assemble Asian, African bush, and African forest elephant genomes for preservation purposes. These genomes were made publicly accessible for research without use restrictions in July 2022 and May 2023, respectively.
In March 2022, Colossal raised $60 million in a Series A funding round led by Thomas Tull, bringing the total funding to $75 million.
Colossal spun out its software platform, Form Bio, in September 2022 with $30 million in funding. Lamm has stated that Colossal is run like a software company, and monetization will stem from technologies developed by the company. Form Bio has developed an AI-based software platform designed to help scientists manage large and complicated datasets.
In January 2023, Colossal completed a Series B funding round, raising an additional $150 million and putting the company's valuation at over $1 billion. The same month, Colossal launched its Conservation Advisory Board, which includes Forrest Galante, Iain Douglas-Hamilton, Mead Treadwell, and Aurelia Skipwith as its members.
In October 2024, Colossal announced $50 million in funding for its launch of the Colossal Foundation.
The company secured $200 million in Series C funding in January 2025, bringing Colossal’s total valuation to $10.2 billion and making it Texas’ first decacorn. With the new funding, Colossal is expanding its work in artificial wombs and de-extinction species. Colossal has raised $435 million in total funding since its foundation.

## Science and development

Because the woolly mammoth and Asian elephant share 99.6% of the same DNA, Colossal aims to develop a proxy species by swapping enough key mammoth genes into the Asian elephant genome. Key mammoth genealogical traits include: a 10-centimeter layer of insulating fat, five different types of shaggy hair, and smaller ears to help the hybrid tolerate cold weather.
Colossal's lab will pair CRISPR/Cas9 with other DNA-editing enzymes, such as integrases, recombinases, and deaminases, to splice woolly mammoth genes into the Asian elephant and has “used 65 different mammoth genomes across about 700,000 years to create an assembled ancient DNA genome”. The company plans on sequencing both elephant and mammoth samples in order to identify key genes in both species to promote population diversification. By doing so, Colossal hopes to prevent any rogue mutations within the hybrid herd. Colossal set a goal for the company to grow a woolly mammoth calf by 2028.
The company plans to use African and Asian elephants as potential surrogates and largely plans to develop artificial elephant wombs lined with uterine tissue as a parallel path to gestation. Colossal scientists plan on creating these embryos by taking skin cells from Asian elephants and reprogramming them into induced pluripotent stem cells which carry mammoth DNA. Lamm stated that Colossal will use both induced pluripotent stem cells (iPSC) as well as somatic cell nuclear transfer in the process.
In July 2022, VGP and Colossal announced that they successfully sequenced the entire Asian elephant genome; this is the first time that mammalian genetic code has been fully sequenced to this degree since the Human Genome Project was completed in the early 2000s.
In August 2022, Colossal announced that they would launch a thylacine research project, in hopes of "de-extincting" the Tasmanian tiger. Colossal plans to reintroduce the thylacine proxy to selected areas in Tasmania and broader Australia and claims that, by doing so, this will re-balance ecosystems that have suffered biodiversity loss and degradation since the species disappeared. A successful thylacine proxy birth could also introduce new marsupial-assisted reproductive technology which can aid in other marsupial conservation efforts. Colossal is partnering with the University of Melbourne, and the project is led by Andrew Pask. The Tasmanian Thylacine Advisory Committee was launched in December 2023.
In January 2023, Colossal announced the formation of its Avian Genomics Group, which will be dedicated to reconstructing the DNA of the dodo bird, which went extinct in the 1600s. Led by Beth Shapiro, who serves as Chief Science Officer to Colossal, this research group aims to create a hybrid composed of specific traits most commonly associated with the dodo and plans to reintroduce these hybrids into their respective environments. Colossal will be working with primordial germ cells to pair dodo DNA with the genome of the Nicobar pigeon, the extinct dodo's closest living relative, and develop chimeric chicks as surrogates for future dodo restoration.
Breaking, a plastic degradation and synthetic biology startup, was launched in April 2024. Gestated at Colossal, Breaking discovered X-32, a microbe that is capable of breaking down various plastics in as little as 22 months while leaving behind carbon dioxide, water and biomass.
It was reported in 2024 that Colossal successfully produced the first-ever elephant and dunnart iPSCs.
In October 2024, the company announced that it had rebuilt a 99.9% accurate genome of the thylacine, using a “pickled” 110-year-old fossilized Tasmanian tiger skull. This marks “the most complete ancient genome of any species known to date” and provides a full DNA blueprint to potentially bring back the Tasmanian tiger. Three months later, in January 2025, the company sequenced the complete genome of the Tasmanian tiger; Colossal also made a prototype for an artificial uterus and used that to culture fertilized single-cell marsupial embryos to over halfway through pregnancy.
In March 2025, Colossal announced the creation of gene-edited "woolly mice" with mutations inspired by woolly mammoths, touting it as a step toward engineering mammoth-like Asian elephants. The mice, which exhibit long, shaggy, tawny-toned fur, were developed using a mix of mammoth-like and known mouse hair-growth mutations. Some experts expressed skepticism, arguing that the experiment was more about mouse genetics than a breakthrough in de-extinction. The company stated that it planned further studies on the mice's cold tolerance and long-term health but had no commercial breeding plans.

### Future de-extinction projects

Outside of their first four projects, Colossal Biosciences has stated that they have a "long list" of species that they want to revive and reintroduce to appropriate ecosystems. Such species include Castoroides, Arctodus, and Steller's sea cow. Ben Lamm has stated that he and his company want to revive Steller's sea cow once they have developed an artificial womb, as there are no adequate living relatives of the extinct sea cow to act a surrogate species. Colossal has also done genetic research for the following species; Irish elk, great auk, bluebuck, ground sloths, moas, saber-tooth cats, long-horned bison, Columbian mammoth, dire wolf, cave hyena, mastodons, American cheetahs, and woolly rhinoceros, with the intent to potentially revive them in the future. Colossal is the first company to apply CRISPR technology to species restoration efforts.

## Conservation

In October 2022, Colossal announced that it was developing a vaccine for elephant endotheliotropic herpesvirus (EEHV), in partnership with the Baylor College of Medicine.
In May 2023, Colossal partnered with the Vertebrate Genomes Project to successfully generate the first high-quality reference genome of an African elephant. This sequencing work is part of a long-term conservation effort for the endangered elephant species.
In September 2023, Colossal partnered with BioRescue to help save the northern white rhino from extinction by using reproduction technology and stem cell technology, as the subspecies is functionally extinct with only two known infertile female members left.
Colossal and Zoos Victoria began a conservation project in October 2023 to preserve the Victorian Grassland Earless Dragon as well as sequence its genome.
In November 2023, Colossal announced a research partnership with Save the Elephants to track African elephants in the Samburu National Reserve. Save the Elephants has already tracked over 900 elephants in the area, using drones equipped with high-resolution infrared cameras. Colossal plans to use pose estimation to develop algorithms for labeling elephants and automatically identifying individual & collective social behavior.
Colossal also began a partnership with the Mauritian Wildlife Foundation in November 2023. Under this collaboration, the organizations will work to restore “critical ecosystems through invasive species removal, revegetation, and community awareness efforts.” Additionally, Colossal will also focus on the rewilding of the dodo bird as well as the genetic rescue of the pink pigeon.
In March 2024, Colossal and Re:wild partnered together to establish a “10-year conservation strategy” to accelerate efforts to “save species on the brink of extinction, search for lost species, and restore key habitats for species recovery and rewilding.”
In May 2024, Colossal and the University of Melbourne announced the successful engineering of cane toad toxin resistance in marsupial cells, as part of conservation efforts for the northern quoll. Colossal’s refined engineering resistance strategy can create over 6,000-fold increased resistance with just one edit to the genome.
The first-ever mRNA vaccine for elephant endotheliotropic herpesvirus (EEHV), developed by Colossal, the Houston Zoo, and the Baylor College of Medicine, was administered to an elephant in July 2024.
In October 2024, Colossal announced its launch of the Colossal Foundation, a non-profit initiative that utilizes Colossal-developed science and technology methods for partner-led conservative efforts. Included in its conservation agenda is the Colossal Biovault, "the world's largest distributed biobanking initiative." The Colossal Biovault collects tissue samples of endangered species in hopes to allow cell lines to become accessible and stored in domestic partner facilities. Its first projects include: Sumatran rhinoceros, red wolf, northern quoll, northern white rhinoceros, pink pigeon, tooth-billed pigeon, Victorian grassland earless dragon, vaquita, African bush elephant, African forest elephant, Asian elephant, and ivory-billed woodpecker. In addition to these species, Colossal plans to biobank the "top 100 most imperilled" species on their Colossal 100 list. However, this list has not been publicly disclosed.
In December 2024, Colossal and University of Melbourne began research into engineering an immunity to chytridiomycosis, a lethal fungal-based disease in amphibians that is responsible for many extinctions and declines in amphibians, including the golden toad, Gastric brooding frog, and Rabbs' fringe-limbed tree frog.

## Reception

In 2022, Colossal was listed as one of the World Economic Forum's Technology Pioneers and was named Genomics Innovation of the Year by the BioTech Breakthrough Awards.
Colossal was included as part of Time's 100 Most Influential Companies 2023 list.
Colossal was voted one of the best places to work in Dallas, Texas, U.S. by Builtin in 2025.