Scientists are closer than ever to creating a mammoth-like animal, but a living creature is still years away. The leading effort, run by the Texas-based company Colossal Biosciences, aims to produce a cold-adapted elephant carrying key woolly mammoth traits. The project has cleared several major biological hurdles that were considered impossible just a few years ago, yet enormous challenges remain between the lab bench and a breathing animal.
Where the Project Stands Today
The core strategy is not to clone a woolly mammoth from ancient DNA. Instead, scientists plan to edit the genome of the Asian elephant, the mammoth’s closest living relative, inserting genes responsible for traits like dense hair, cold-tolerant blood, and thick fat layers. The two species share roughly 99.6% of their DNA, which means the editing task is focused on a relatively small number of targeted changes rather than building a genome from scratch.
The single biggest breakthrough so far came when researchers successfully created induced pluripotent stem cells (iPSCs) from Asian elephant tissue for the first time. These are lab-reprogrammed cells that can theoretically grow into any cell type in the body. For most lab animals, iPSCs are a routine tool. For elephants, they had never been achieved, because elephant cells carry extra copies of a powerful tumor-suppressing gene that aggressively kills off cells showing the kind of rapid growth iPSCs require. The team solved this by developing a two-step process that chemically coaxes the cells into a flexible state while carefully dialing down that tumor-defense pathway. With iPSCs in hand, scientists can now test mammoth gene edits in elephant cells in the lab, observe how the changes affect cell behavior, and refine their approach before ever attempting to produce an embryo.
Which Genes Are Being Targeted
Comparative genome studies between woolly mammoths and modern elephants have mapped out the genetic differences that made mammoths suited to Arctic life. The priority edits focus on a handful of functional categories:
- Cold-tolerant hemoglobin. Mammoths carried specific substitutions in their hemoglobin genes that allowed their blood to deliver oxygen efficiently at low body temperatures, something modern elephant blood cannot do.
- Fat metabolism. Mammoth genomes show unique changes in genes governing lipid storage and metabolism, which would have supported the thick subcutaneous fat layer insulating them against extreme cold.
- Hair and skin. Multiple gene variants are linked to dense fur growth and skin adaptations absent in modern elephants.
- Circadian rhythms. Living through months of polar darkness or continuous summer light required internal clocks tuned differently from those of tropical elephants.
- Immune defense. One striking finding is a dramatic amplification of a gene involved in antiviral defense, with some mammoth genomes carrying up to nine copies. This may have been an adaptation to pathogen pressures in mammoth herds.
Researchers have sequenced DNA from mammoths over a million years old, shattering previous records for ancient DNA recovery. Having multiple mammoth genomes from different time periods lets the team distinguish genuine adaptive traits from random variation in any single specimen.
The Hardest Problems Still Unsolved
Editing genes in a dish is very different from producing a living elephant-mammoth hybrid. The largest unsolved problem is reproductive biology. To create an embryo, scientists would need to perform a process called somatic cell nuclear transfer, essentially placing an edited cell’s nucleus into an egg cell stripped of its own DNA. This technique produced Dolly the sheep in 1996 and has worked in a handful of other species, but it has never succeeded in elephants.
When researchers have attempted cross-species nuclear transfer using elephant DNA and pig egg cells, the embryos stall at very early stages. Three interrelated problems explain why. First, the molecular machinery of the egg cell and the transplanted nucleus don’t communicate properly, disrupting the activation of critical genes the embryo needs to start developing. Second, the energy-producing structures in the egg (mitochondria) don’t match the transplanted nucleus’s instructions, starving the embryo of energy at a cellular level. Third, the egg fails to fully erase the donor cell’s original identity, so the embryo can’t establish the blank-slate state needed to build a new organism. Each of these barriers compounds the others, and solving them in elephants remains an active area of research with no guaranteed timeline.
Even if a viable embryo were created, gestation poses its own challenge. Elephants carry their young for roughly 22 months, the longest pregnancy of any land mammal. Using a surrogate Asian elephant mother raises welfare concerns and logistical difficulties, since Asian elephants are themselves endangered. Some researchers have floated the idea of an artificial womb, but current technology can sustain premature lambs for only a few weeks. Scaling that to a 22-month elephant pregnancy is far beyond anything that exists today.
The Environmental Case for a Mammoth Proxy
Proponents argue that mammoth-like animals aren’t just a scientific curiosity. They could play a role in slowing permafrost loss across the Arctic. The reasoning draws on an ecological experiment already underway in northeastern Siberia called Pleistocene Park, where researchers have reintroduced bison, horses, and other large herbivores to test whether grazing animals can restore ancient grassland ecosystems.
The theory works like this: large herds trample snow in winter, compacting it and removing its insulating effect. That exposes the ground to brutally cold air temperatures, keeping the permafrost frozen harder and deeper. In summer, grasslands maintained by grazing reflect more sunlight than dark forest or shrubland, reducing heat absorption. And grass root systems stabilize soil, preventing the erosion that accelerates thaw. The carbon stakes are enormous. Arctic permafrost soils hold more carbon than all the world’s rainforests combined. If that carbon escapes as greenhouse gases due to warming, the climate consequences would be severe. Restoring grassland-herbivore systems is one proposed strategy for keeping it locked in the ground.
A cold-adapted elephant could, in theory, fill the ecological role mammoths once played: knocking down trees, spreading seeds, and maintaining open grassland. Whether a small number of lab-born animals could ever scale into wild herds large enough to reshape Arctic landscapes is a separate, much harder question.
Ethical and Legal Gray Zones
In 2016, the International Union for the Conservation of Nature published the first formal guidelines for de-extinction. The IUCN defined the goal not as creating “faithful replicas” of extinct species but as generating functional proxies that fill the ecological role the original species once occupied. The guidelines recognize three possible methods: selective breeding, genome editing, and cloning.
One unresolved legal problem is that existing wildlife laws were written to protect living species and their established habitats. An extinct species has no recognized native range under current regulations, which creates a gray area for where a mammoth proxy could legally be released, who would manage it, and what protections it would receive. No country has passed legislation specifically addressing de-extinction.
There are also conservation-priority concerns. Asian elephants are endangered, and critics question whether the financial and scientific resources flowing into mammoth de-extinction would do more good if directed toward saving species that are still alive but declining. Colossal has argued that the reproductive and genetic technologies it develops will have direct applications for endangered species conservation, but that promise remains largely unproven.
A Realistic Timeline
Colossal Biosciences has publicly targeted the late 2020s for the birth of a first mammoth-like calf, though independent scientists have expressed skepticism about that pace. The iPSC breakthrough was a necessary first step, but the jump from edited cells in a petri dish to a living, breathing animal involves reproductive milestones that have never been achieved in any elephant species. Each of those milestones, creating a viable embryo, successfully implanting it, and sustaining a full-term pregnancy, could take years of trial and error on its own.
A more cautious reading of the science suggests the first mammoth-like animal, if it arrives at all, is probably a project measured in decades rather than years. What scientists have right now is a powerful genetic toolkit, a clear map of the edits needed, and the first real ability to test those edits in elephant cells. What they don’t yet have is a proven way to turn an edited cell into a living animal. That gap is the defining challenge of the entire effort.