Revival of the woolly mammoth

Last updated
Model of a woolly mammoth at the Royal BC Museum Woolly mammoth model Royal BC Museum in Victoria.jpg
Model of a woolly mammoth at the Royal BC Museum

The revival of the woolly mammoth is a proposed hypothetical that frozen soft-tissue remains and DNA from extinct woolly mammoths could be a means of regenerating the species. Several methods have been proposed to achieve this goal, including cloning, artificial insemination, and genome editing. Whether or not it is ethical to create a live mammoth is debated.

Contents

In 2003, the Pyrenean ibex was briefly revived, giving credence to the idea that the mammoth could be successfully revived.

Overview

In theory, preserved genetic material found in remains of woolly mammoths could be used to recreate living mammoths, due to advances in molecular biology techniques and the cloning of mammals, begun with Dolly the Sheep in 1996. [1] [2] [3] Cloning of mammals has improved in the last two decades. To date, no viable mammoth tissue or its intact genome has been found to attempt cloning.

According to Beth Shapiro, a scientist who has taken a central role in the sequencing of the mammoth genome, states in her 2015 book How to Clone a Mammoth: The Science of De-Extinction , that a mammoth will never be cloned, at least not one that is pure mammoth. Nevertheless, the book concludes that we are likely, at some point, to see something that resembles a mammoth. [4] Comparative genomics shows that the mammoth genome matches 99% of the elephant genome, so researchers working in the field aim to engineer an elephant with mammoth genes, that code for the external appearance and traits of a mammoth. [5] The outcome would be an elephant-mammoth hybrid with no more than 1% mammoth genes. [5] Separate projects are working on gradually adding mammoth genes to elephant cells in vitro . [1] [2] [6]

Colossal Biosciences, founded in 2021, is one biotechnology company that has publicly stated that its project is to genetically resurrect the woolly mammoth, combining its genes with Asian elephant DNA. It has publicly stated that it intends to complete the project by 2027. [7] [8] [9] [10]

Cloning

Cloning involves removal of the DNA-containing nucleus of the egg cell of a female elephant, and replacement with a nucleus from woolly mammoth tissue, a process called somatic cell nuclear transfer. For example, Akira Iritani, at the Kyoto University in Japan, reportedly planned to do this. [11] The cell would then be stimulated into dividing, and implanted in a female elephant. The resulting calf would have the genes of the woolly mammoth. However, nobody as of date has found a viable mammoth cell to begin the cloning process, and most scientists doubt that any living cell could have survived freezing in the tundra of the Arctic. [12] [13] [14] [15] Because of their conditions of preservation, the DNA of frozen mammoths has deteriorated significantly over the millennia. [16] [17]

Artificial insemination

A second method involves artificially inseminating an elephant egg cell with sperm cells from a frozen woolly mammoth carcass. The resulting offspring would be an elephant–mammoth hybrid, and the process would have to be repeated, so more hybrids could be used in breeding. After several generations of cross-breeding these hybrids, an almost pure woolly mammoth would be produced. Whether the hybrid embryo would be carried through the two-year gestation is unknown; in one case, an Asian elephant and an African elephant produced a live calf named Motty, but it died of defects at less than two weeks old. [18] There is also another fact to consider, that sperm cells of modern mammals are viable for 15 years at most after deep-freezing. This makes this method unfeasible. [17]

Model depicting the calf "Dima", Stuttgart Dima baby mammoth model.jpg
Model depicting the calf "Dima", Stuttgart

Gene editing

In April 2015, Swedish scientists published the complete genome (nuclear DNA sequence) of the woolly mammoth. [1] [19] Several projects are working on gradually replacing the genes in elephant cells with mammoth genes. [1] [2] One such project is that of Harvard University geneticist George M. Church, who is funded by the Long Now Foundation, [1] [2] is attempting to create a mammoth–elephant hybrid using DNA from frozen mammoth carcasses. According to the researchers, a mammoth cannot be recreated, but they will try to eventually grow a hybrid elephant with some woolly mammoth traits in an "artificial womb". [20] [21] In 2017, George Church said "Actually it would be more like an elephant with a number of mammoth traits. We're not there yet, but it could happen in a couple of years." The creature, sometimes referred as a "mammophant", would be partly elephant, but with features such as small ears, subcutaneous fat, long shaggy hair and cold-adapted blood. [22] The Harvard University team is attempting to study the animals' characteristics in vitro by replacing or editing some specific mammoth genes into Asian elephant skin cells called fibroblasts that have the potential to become embryonic stem cells. [23] By March 2015 and using the new CRISPR DNA editing technique, Church's team had some woolly mammoth genes edited into the genome of an Asian elephant; focusing on cold-resistance initially, [12] the target genes are for the external ear size, subcutaneous fat, hemoglobin, and hair attributes. [23] [24] By February 2017, Church's team had made 45 substitutions to the elephant genome. [20] So far his work focuses solely on single cells. In 2021, Church received $15 million in funding and spun off a new company called Colossal. [25]

The Mammoth Genome Project at Pennsylvania State University is also researching the modification of African elephant DNA to create a mammoth–elephant hybrid. [26] If a viable hybrid embryo is obtained by gene editing procedures, implanting it into a female Asian elephant housed in a zoo may be possible, [1] but with the current knowledge and technology, whether the hybrid embryo would be carried through the two-year gestation is unknown. [27] [28]

Ethics

Modern elephants are highly gregarious, as shown by these Sri Lankan elephants Elephants by the water (7568684536).jpg
Modern elephants are highly gregarious, as shown by these Sri Lankan elephants

If any method is ever successful, a suggestion has been made to introduce the hybrids to a wildlife reserve in Siberia called the Pleistocene Park, [29] but some biologists question the ethics of such recreation attempts. [30] In addition to the technical problems, not much habitat is left that would be suitable for mammoth–elephant hybrids. Because both species are [were] social and gregarious, creating a few specimens would not be ideal. The time and resources required would be enormous, and the scientific benefits would be unclear, suggesting these resources should instead be used to preserve extant elephant species which are endangered. [17] [31] The ethics of using elephants as surrogate mothers in hybridisation attempts has also been questioned, as most embryos would not survive, and knowing the exact needs of a hybrid mammoth–elephant calf would be impossible. [14]

Woolly mammoths and sustainability

Researchers from the company Colossal confirmed that their primary goal when trying to revive the woolly mammoth is to better the environment and climate change itself. [32]

See also

Related Research Articles

<span class="mw-page-title-main">Cloning</span> Process of producing individual organisms with identical genomes

Cloning is the process of producing individual organisms with identical genomes, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction; this reproduction of an organism by itself without a mate is known as parthenogenesis. In the field of biotechnology, cloning is the process of creating cloned organisms of cells and of DNA fragments.

<span class="mw-page-title-main">Dolly (sheep)</span> First cloned mammal (1996–2003)

Dolly was a female Finn-Dorset sheep and the first mammal that was cloned from an adult somatic cell. She was cloned by associates of the Roslin Institute in Scotland, using the process of nuclear transfer from a cell taken from a mammary gland. Her cloning proved that a cloned organism could be produced from a mature cell from a specific body part. Contrary to popular belief, she was not the first animal to be cloned.

<span class="mw-page-title-main">Mammoth</span> Extinct genus of mammals

A mammoth is any species of the extinct elephantid genus Mammuthus. They lived from the late Miocene epoch into the Holocene about 4,000 years ago, and various species existed in Africa, Europe, Asia, and North America. Mammoths are distinguished from living elephants by their spirally twisted tusks and in at least some later species, the development of numerous adaptions to living in cold environments, including a thick layer of fur.

<span class="mw-page-title-main">Hybrid (biology)</span> Offspring of cross-species reproduction

In biology, a hybrid is the offspring resulting from combining the qualities of two organisms of different varieties, subspecies, species or genera through sexual reproduction. Generally, it means that each cell has genetic material from two different organisms, whereas an individual where some cells are derived from a different organism is called a chimera. Hybrids are not always intermediates between their parents such as in blending inheritance, but can show hybrid vigor, sometimes growing larger or taller than either parent. The concept of a hybrid is interpreted differently in animal and plant breeding, where there is interest in the individual parentage. In genetics, attention is focused on the numbers of chromosomes. In taxonomy, a key question is how closely related the parent species are.

<span class="mw-page-title-main">Somatic cell nuclear transfer</span> Method of creating a cloned embryo by replacing the egg nucleus with a body cell nucleus

In genetics and developmental biology, somatic cell nuclear transfer (SCNT) is a laboratory strategy for creating a viable embryo from a body cell and an egg cell. The technique consists of taking a denucleated oocyte and implanting a donor nucleus from a somatic (body) cell. It is used in both therapeutic and reproductive cloning. In 1996, Dolly the sheep became famous for being the first successful case of the reproductive cloning of a mammal. In January 2018, a team of scientists in Shanghai announced the successful cloning of two female crab-eating macaques from foetal nuclei.

Commercial animal cloning is the cloning of animals for commercial purposes, including animal husbandry, medical research, competition camels and horses, pet cloning, and restoring populations of endangered and extinct animals. The practice was first demonstrated in 1996 with Dolly the sheep.

<span class="mw-page-title-main">Designer baby</span> Genetically modified human embryo

A designer baby is a baby whose genetic makeup has been selected or altered, often to exclude a particular gene or to remove genes associated with disease. This process usually involves analysing a wide range of human embryos to identify genes associated with particular diseases and characteristics, and selecting embryos that have the desired genetic makeup; a process known as preimplantation genetic diagnosis. Screening for single genes is commonly practiced, and polygenic screening is offered by a few companies. Other methods by which a baby's genetic information can be altered involve directly editing the genome before birth, which is not routinely performed and only one instance of this is known to have occurred as of 2019, where Chinese twins Lulu and Nana were edited as embryos, causing widespread criticism.

<span class="mw-page-title-main">Columbian mammoth</span> Extinct species of mammoth that inhabited North America

The Columbian mammoth is an extinct species of mammoth that inhabited North America from southern Canada to Costa Rica during the Pleistocene epoch. The Columbian mammoth descended from Eurasian steppe mammoths that colonised North America during the Early Pleistocene around 1.5–1.3 million years ago, and later experienced hybridisation with the woolly mammoth lineage. The Columbian mammoth was among the last mammoth species, and the pygmy mammoths evolved from them on the Channel Islands of California. The closest extant relative of the Columbian and other mammoths is the Asian elephant.

<span class="mw-page-title-main">George Church (geneticist)</span> American geneticist

George McDonald Church is an American geneticist, molecular engineer, chemist, serial entrepreneur, and pioneer in personal genomics and synthetic biology. He is the Robert Winthrop Professor of Genetics at Harvard Medical School, Professor of Health Sciences and Technology at Harvard University and Massachusetts Institute of Technology, and a founding member of the Wyss Institute for Biologically Inspired Engineering at Harvard University.

A frozen zoo is a storage facility in which genetic materials taken from animals are stored at very low temperatures (−196 °C) in tanks of liquid nitrogen. Material preserved in this way can be stored indefinitely and used for artificial insemination, in vitro fertilization, embryo transfer, and cloning. There are a few frozen zoos across the world that implement this technology for conservation efforts. Several different species have been introduced to this technology, including the Pyrenean ibex, Black-footed ferret, and potentially the white rhinoceros.

<span class="mw-page-title-main">Woolly mammoth</span> Extinct species from the Quaternary period

The woolly mammoth is an extinct species of mammoth that lived from the Middle Pleistocene until its extinction in the Holocene epoch. It was one of the last in a line of mammoth species, beginning with the African Mammuthus subplanifrons in the early Pliocene. The woolly mammoth began to diverge from the steppe mammoth about 800,000 years ago in Siberia. Its closest extant relative is the Asian elephant. The Columbian mammoth lived alongside the woolly mammoth in North America, and DNA studies show that the two hybridised with each other.

<span class="mw-page-title-main">Genetically modified animal</span> Animal that has been genetically modified

Genetically modified animals are animals that have been genetically modified for a variety of purposes including producing drugs, enhancing yields, increasing resistance to disease, etc. The vast majority of genetically modified animals are at the research stage while the number close to entering the market remains small.

The Jarkov Mammoth, is a woolly mammoth specimen discovered on the Taymyr Peninsula of Siberia by a nine-year-old boy in 1997. This particular mammoth is estimated to have lived about 20,000 years ago. It is likely to be male and probably died at age 47.

<span class="mw-page-title-main">De-extinction</span> Process of re-creating an extinct species

De-extinction is the process of generating an organism that either resembles or is an extinct species. There are several ways to carry out the process of de-extinction. Cloning is the most widely proposed method, although genome editing and selective breeding have also been considered. Similar techniques have been applied to certain endangered species, in hopes to boost their genetic diversity. The only method of the three that would provide an animal with the same genetic identity is cloning. There are benefits and drawbacks to the process of de-extinction ranging from technological advancements to ethical issues.

<span class="mw-page-title-main">Molecular paleontology</span>

Molecular paleontology refers to the recovery and analysis of DNA, proteins, carbohydrates, or lipids, and their diagenetic products from ancient human, animal, and plant remains. The field of molecular paleontology has yielded important insights into evolutionary events, species' diasporas, the discovery and characterization of extinct species.

<span class="mw-page-title-main">Pyrenean ibex</span> Extinct subspecies of Iberian ibex

The Pyrenean ibex, Aragonese and Spanish common name bucardo, Basque common name bukardo, Catalan common name herc and French common name bouquetin, was one of the four subspecies of the Iberian ibex or Iberian wild goat, a species endemic to the Pyrenees. Pyrenean ibex were most common in the Cantabrian Mountains, Southern France, and the northern Pyrenees. This species was common during the Holocene and Upper Pleistocene, during which their morphology, primarily some skulls, of the Pyrenean ibex was found to be larger than other Capra subspecies in southwestern Europe from the same time.

<i>How to Clone a Mammoth</i> 2015 popular science book by Beth Shapiro

How to Clone a Mammoth: The Science of De-Extinction is a 2015 non-fiction book by biologist Beth Shapiro and published by Princeton University Press. The book describes the current state of de-extinction technology and what the processes involved require in order to accomplish the potential resurrection of extinct species.

Human germline engineering is the process by which the genome of an individual is edited in such a way that the change is heritable. This is achieved by altering the genes of the germ cells, which then mature into genetically modified eggs and sperm. For safety, ethical, and social reasons, there is broad agreement among the scientific community and the public that germline editing for reproduction is a red line that should not be crossed at this point in time. There are differing public sentiments, however, on whether it may be performed in the future depending on whether the intent would be therapeutic or non-therapeutic.

Revive & Restore is a nonprofit wildlife conservation organization focused on use of biotechnology in conservation. Headquartered in Sausalito, California, the organization's mission is to enhance biodiversity through the genetic rescue of endangered and extinct species. The organization was founded by Stewart Brand and his wife, Ryan Phelan.

Colossal Biosciences Inc. is an American biotechnology and genetic engineering company working to de-extinct the woolly mammoth, the Tasmanian tiger, and the dodo. 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.

References

  1. 1 2 3 4 5 6 Mammoth genome sequence completed. BBC News, 23 April 2015.
  2. 1 2 3 4 The Long Now Foundation - Revive and Restore.
  3. ↑ Timmons, Jeanne (January 7, 2013). "Could Ancient Giants Be Cloned? Is It Possible, And Is It Wise?". Valley News.
  4. ↑ De-extinction and Conservation. Gregory E. Kaebnick, and Bruce Jennings. The Hastings Center Report. 26 July 2017
  5. 1 2 The Mammoth Genome Project. Pennsylvania State University. Accessed: October 2018.
  6. ↑ "Mammoth: Back from the Dead" Archived 2014-01-06 at the Wayback Machine . National Geographic Channel.
  7. ↑ "The Woolly Mammoth Will Be Back In 6 Years". Colossal. 2021-09-13. Retrieved 2024-05-23.
  8. ↑ Banias, M. J. (2021-09-13). "The Woolly Mammoth Will Be Back In 6 Years, Says New Start-Up in Partnership with Harvard University". The Debrief. Retrieved 2024-05-23.
  9. ↑ Zimmer, Carl (2021-09-13). "A New Company With a Wild Mission: Bring Back the Woolly Mammoth". The New York Times. Retrieved 2021-10-26.
  10. ↑ Michael Greshko (September 13, 2021). "Mammoth-elephant hybrids could be created within the decade. Should they be?". National Geographic. Archived from the original on September 13, 2021.
  11. ↑ Lendon, Brad (January 17, 2011). "Scientists trying to clone, resurrect extinct mammoth". CNN News. Archived from the original on 2013-10-29. Retrieved 2023-12-04.
  12. 1 2 Landers, Jackson (February 9, 2015). "Can scientists bring mammoths back to life by cloning?". The Washington Post . Retrieved 2023-12-04.
  13. ↑ Zimmer, Carl (April 2013). "Bringing Them Back to Life". National Geographic. Archived from the original on 2017-03-29. Retrieved 2023-12-04.
  14. 1 2 Loi, Pasqualino; Saragusty, Joseph; Ptak, Grazyna (2014), Holt, William V.; Brown, Janine L.; Comizzoli, Pierre (eds.), "Cloning the Mammoth: A Complicated Task or Just a Dream?", Reproductive Sciences in Animal Conservation, Advances in Experimental Medicine and Biology, vol. 753, New York, NY: Springer New York, pp. 489–502, doi:10.1007/978-1-4939-0820-2_19, ISBN   978-1-4939-0819-6, PMID   25091921 , retrieved 2022-10-23
  15. ↑ Shapiro, 2015. p. 11
  16. ↑ Timmons, Jeanne (7 January 2013). "Could Ancient Giants Be Cloned? Is It Possible, And Is It Wise?". Valley News. Archived from the original on 30 March 2015.
  17. 1 2 3 Lister, 2007. pp. 42–43
  18. ↑ Stone, R. (1999). "Cloning the Woolly Mammoth". Discover Magazine. Archived from the original on 29 July 2014.
  19. ↑ Dalén, Love; Palkopoulou, Eleftheria; Mallick, Swapan; et al. (18 May 2015). "Complete Genomes Reveal Signatures of Demographic and Genetic Declines in the Woolly Mammoth". Current Biology. 25 (10): 1395–1400. Bibcode:2015CBio...25.1395P. doi:10.1016/j.cub.2015.04.007. PMC   4439331 . PMID   25913407.
  20. 1 2 Reviving woolly mammoth will take more than 2 years Archived 8 October 2017 at the Wayback Machine . BBC News. Helen Pilcher, 22 February 2017.
  21. ↑ Kaebnick, Gregory E.; Jennings, Bruce (2017). "De-extinction and Conservation". Hastings Center Report. 47: S2–S4. doi: 10.1002/hast.744 . PMID   28746761.
  22. ↑ Church, George (February 16, 2017). "Woolly mammoth on verge of resurrection, scientists reveal". The Guardian.
  23. 1 2 Webster, Ben (2015-03-23). "Scientist takes mammoth-cloning a step closer". The Sunday Times .
  24. ↑ Sarah Fecht (24 March 2014), Woolly Mammoth DNA Successfully Spliced Into Elephant Cells, Popular Science, archived from the original on 26 March 2015
  25. ↑ Herper, Matthew (September 13, 2021). "Return of the mammoth? George Church-backed company launches with $15 million for elephant-sized quest".
  26. ↑ Scientists Hoped to Have Cloned a Living Woolly Mammoth by Now — Why Haven't We? Archived 8 October 2017 at the Wayback Machine . Sveta McShane. 17 August 2016. Singularity Hub.
  27. ↑ The Plan to Turn Elephants Into Woolly Mammoths Is Already Underway Archived 24 April 2015 at the Wayback Machine . 21 May 2014.
  28. ↑ "Scientists Sequence Woolly-Mammoth Genome". Mammoth Genome Project. Pennsylvania State University. Archived from the original on 2008-12-02. Retrieved 6 November 2014.
  29. ↑ Zimov, S. A. (2005). "Essays on Science and Society: Pleistocene Park: Return of the Mammoth's Ecosystem" (PDF). Science. 308 (5723): 796–798. doi: 10.1126/science.1113442 . PMID   15879196.
  30. ↑ An Analysis of Potential Ethical Justifications for Mammoth De-extinction And a Call for Empirical Research. Yasha Rohwer and Emma Marris. Ethics, Policy & Environment; Volume 21, 2018; Issue 1; pages: 127-142.
  31. ↑ Griffin, A. (23 March 2015). "Woolly mammoth could be revived after scientists paste DNA into elephant's genetic code". The Independent. Archived from the original on 25 September 2015.
  32. ↑ Star, The San Juan Daily (November 1, 2021). "A new company with a wild mission: Bring back the woolly mammoth". San Juan Daily Star.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.