Woolly mammoth by Colossal Biosciences

Milestones

Next · Edited elephant embryos and a pregnancy

Lab-made elephant stem cellsMar 2024Complete.
Woolly mice with mammoth-like hairMar 2025Complete.
Edited elephant embryos and a pregnancyNowCurrent milestone.
First mammoth-trait elephant calfTarget 2028Not yet reached.

Most important updates

Mar 2025
12 Jul 2022

Upcoming

2028First mammoth-trait elephant calf (next)

Current obstacles

Who carries the baby?Using endangered elephants as surrogates is ethically fraught; artificial wombs for big animals don't exist.
So many edits at onceMaking dozens of precise edits in one cell without damaging its DNA is at the edge of what's possible.

Physics limits

Ancient DNA breaks down with timeDNA decays even when frozen: bone studies give a half-life of about 521 years for its chemical bonds. Mammoth genomes survive only as short fragments that must be pieced together.
Only a few differences can be edited inMammoth and Asian elephant genomes differ at over a million letters. Editing dozens of chosen genes gives an elephant with mammoth traits, not a mammoth.
Elephant pregnancies are slowAn elephant pregnancy lasts about 22 months, and elephants mature in over a decade. Each attempt takes years, and there are few surrogate mothers.

How it works

3 parts

An Asian elephant: the mammoth's closest living relative, whose cells Colossal edits toward mammoth traitsPhoto: Cliff from Arlington, Virginia, USA · CC BY 2.0 (opens commons.wikimedia.org)

Compare

Compare mammoth and elephant

Compare mammoth DNA from frozen remains with Asian elephant DNA to find genes for hair, fat and feeling cold.

Test

Try it in mice first

Make matching edits in mice to check they give the expected traits.

Build

Edit elephant cells

Make dozens of edits in elephant cells, then create embryos by cloning.

Spec sheet

Spec	Woolly mammoth
Elephant gestation	~22 months^R (reported)
Target first calf	2028^R (reported)

^R reported by the company

Papers & demos

1 item

Mar 2025paper
Multiplex-edited mice recapitulate woolly mammoth hair phenotypes (preprint) (opens doi.org)Many edits at once to hair and fat genes gave mice long, woolly coats.

Update log

2 updates

Mar 2025

Minor: PressResearch

Tue 12 Jul 2022

Minor: PressResearch

About Colossal Biosciences

The team behind Woolly mammoth

Colossal Biosciences

De-extinction, dire wolf, woolly mammoth

Dallas company co-founded by Ben Lamm and George Church that edits living animals to carry traits of extinct ones: mammoth, thylacine, dodo, moa. In 2025 it announced wolf pups edited with dire wolf traits and 'woolly mice'.

Apr 2025: announced three pups cloned from gray wolf cells with 20 edits in 14 genes chosen from ancient dire wolf DNA.
Many scientists, including the IUCN wolf and dog experts, say they are modified gray wolves, not dire wolves.
Reported in Jul 2026 to be raising at a $20–30B valuation, up from $10.2B in Jan 2025.

colossal.com (opens colossal.com)Company profile →

Founded: 20215 yrs
Headquarters: United States
Status: Private
Valuation: $10BprivateJan 2025
Raised: $350M2 rounds
Last round: Series C · $200MJan 2025$10B post
Works in: BiotechDe-extinction
Coverage: 2 programs · 7 updateslatest 1 Jul 2026checked 25 Sep
Lead investors: TWG GlobalUS Innovative Technology Fund
Partners: Form Bio (opens formbio.com)University of Melbourne (opens unimelb.edu.au)
Investors: TWG Global
People: Ben Lamm (opens en.wikipedia.org)Co-founder and CEOGeorge Church (opens en.wikipedia.org)Co-founderBeth Shapiro (opens en.wikipedia.org)Chief Science Officer