Commercial animal cloning

Commercial animal cloning is the cloning of animals for commercial purposes. Currently, pets are being cloned commercially, along with livestock, competition camels and horses and even endangered and extinct animals.[1]

Pet cloningEdit

Pet cloning is one example of commercial animal cloning, and it is the process of using genes from one domestic (pet) animal to form a second, genetically identical, animal. This cloning is usually done through a process known as somatic cell nuclear transfer (SCNT).[2] In this process, an oocyte is taken from a surrogate mother and put through enucleation, a process that removes the nucleus from inside the oocyte. Somatic cells are then taken from the animal that is being cloned, transferred into the blank oocyte in order to provide genetic material, and fused with the oocyte using an electrical current. The oocyte is then activated and re-inserted into the surrogate mother. The end result is the formation of an animal that is almost genetically identical to the animal the somatic cells were taken from.[2][3] While SCNT was previously believed to only work using genetic material from somatic cells that were unfrozen or were frozen with cryoprotectant (to avoid cell damage caused by freezing), successful dog cloning in various breeds has now been shown using somatic cells from unprotected specimens that had been frozen for up to four days.[4] Another method of pet cloning includes embryo splitting, the process of taking the blastomeres from a very early animal embryo and separating them before they become differentiated in order to create two or more separate organisms. When using embryo splitting, pet cloning must occur before the birth of the pet, and clones grow up at the same time that the original pet does (in a similar fashion to monozygotic twins).[2]

Livestock cloningEdit

Livestock is being cloned in certain centres (i.e. Tianjin animal cloning center, ...).[clarification needed]

Competition horses and camelsEdit

Polo horses[5] and camels[6] are being cloned for competition use. Horse cloning is often referred to as "equine cloning". In 2012, Féderation Equestre Internationale (FEI) lifted a ban on horse cloning, allowing them to compete.[7][8][9]

Endangered and extinct animalsEdit

Endangered and extinct animals are also being cloned in certain centers (i.e. Tianjin animal cloning center, ...). This is also referred to as "Conservation cloning".[10][11]

HistoryEdit

The first commercially cloned pet was a cat named Little Nicky, produced in 2004 by Genetic Savings & Clone for a north Texas woman for the fee of US$50,000.[12] On May 21, 2008, BioArts International[13] announced a limited commercial dog cloning service (through a program it called Best Friends Again) in partnership with a Korean company named Sooam Biotech. This program came after the announcement of the successful cloning of a family dog named Missy, an achievement widely publicized in the Missyplicity Project. In September 2009, BioArts announced the end of its dog cloning service.[14] In July 2008, the Seoul National University (co-parents of Snuppy, reputedly the world's first cloned dog in 2005) created five clones of a dog named Booger for its Californian owner. The woman paid $50,000 for this service.[15]

Sooam Biotech continued developing proprietary techniques for cloning dogs[16] based on a licence from ViaGen's subsidiary Start Licensing (which owned the original patent for cloning Dolly the sheep[17]). Sooam created cloned puppies for owners whose dogs had died, charging $100,000 per clone.[18][19] Sooam Biotech was reported to have cloned approximately 700 dogs by 2015[18] and to be producing 500 cloned embryos of various breeds a day in 2016.[20] In 2015, the longest period after which Sooam Biotech could clone a puppy was 12 days from the death of the original pet dog.[21] Sinogene Biotechnology created the first Chinese clone dog in 2017 before commercializing the cloning service and joining in the pet cloning market.[22] In 2019, Sinogene successfully created the first Chinese cloned cat.[23]

ControversiesEdit

Animal welfareEdit

The mortality rate for cloned animals is higher than for those born of natural processes. This includes a discrepancy pre-birth, during birth, and after birth in survival rates and quality of life, leading to ethical concerns.[24] Many of these discrepancies are thought to come from maternal mRNA already present in the oocyte prior to the transfer of genetic material as well as from DNA methylation, both of which contribute to the development of the animal in the womb of the surrogate.[25] Some common issues seen with cloned animals are shortened telomeres, the repetitive end sequences of DNA whose decreasing length over the lifespan of an organism have been associated with aging;[26] large offspring syndrome, the abnormal size of cloned individuals due to epigenetic (gene expression) changes; and methylation patterns of genetic material that are so abnormal compared to standard embryos of the species being cloned as to be incompatible with life.[25]

Pet cloningEdit

While pet cloning is sometimes advertised as a prospective method for re-gaining a deceased companionship animal, pet cloning does not result in animals that are exactly like the previous pet (in looks or personality).[27] Although the animal in question is cloned, there are still phenotypical differences that may affect its appearance or health. This issue was brought to light in the cloning of a cat named Rainbow. Rainbow's clone, later named CC, was genetically identical to Rainbow, yet CC's coloring patterns were not the same due to the development of the kitten inside the womb as well as random genetic disparities in the clone such as variable X-chromosome inactivation.[28]

Despite its controversies, the study of pet cloning holds the potential to contribute to scientific, veterinary, and medical knowledge, and it is a potential resource in efforts to preserve endangered cousins of the cat and dog.[26]

In 2005, California Assembly Member Lloyd Levine introduced a bill to ban the sale or transfer of pet clones in California.[29] That bill was voted down.[30]

See alsoEdit

ReferencesEdit

  1. ^ Medicine, Center for Veterinary (2020-06-11). "A Primer on Cloning and Its Use in Livestock Operations". FDA.
  2. ^ a b c Keefer, Carol (July 21, 2015). "Artificial cloning of domestic animals". Proceedings of the National Academy of Sciences. 112 (29): 8874–8. Bibcode:2015PNAS..112.8874K. doi:10.1073/pnas.1501718112. PMC 4517265. PMID 26195770.
  3. ^ Kim, Min Jung; Oh, Hyun Ju; Kim, Geon A; Setyawan, Erif Maha Nugraha; Choi, Yoo Bin; Lee, Seok Hee; Petersen-Jones, Simon M.; Ko, CheMyong J.; Lee, Byeong Chun (November 10, 2017). "Birth of clones of the world's first cloned dog". Scientific Reports. 7 (1): 15235. Bibcode:2017NatSR...715235K. doi:10.1038/s41598-017-15328-2. PMC 5681657. PMID 29127382.
  4. ^ Jeong, Yeonik; Olson, Olof P.; Lian, Cai; Lee, Eun Song; Jeong, Yeon Woo; Hwang, Woo Suk (2020-12-01). "Dog cloning from post-mortem tissue frozen without cryoprotectant". Cryobiology. 97: 226–230. doi:10.1016/j.cryobiol.2020.03.013. ISSN 0011-2240. PMID 32268132.
  5. ^ Cohen, Haley. "How Champion-Pony Clones Have Transformed the Game of Polo". Vanity Fair. Retrieved 2021-03-07.
  6. ^ "How UAE camel cloning became an industry worth millions of dirhams". The National. 2021-02-19. Retrieved 2021-03-07.
  7. ^ MEDRANO, KASTALIA (2012-08-05). "Cloned Horses Coming to the Olympics?". nationalgeographic.com. Retrieved 2021-03-07.
  8. ^ White, Charlotte (2012-06-29). "Cloned horses may now compete says FEI". Horse & Hound. Retrieved 2021-03-07.
  9. ^ "Horse International: Equine cloning: the legal aspects". European Us Asian Equine Lawyers - EUAEL. 2017-08-15. Retrieved 2021-03-07.
  10. ^ Marshall, Andrew (2000-11-01). "Cloning for conservation". Nature Biotechnology. 18 (11): 1129. doi:10.1038/81057. ISSN 1546-1696. PMID 11062403.
  11. ^ "Debating Science|Conservation Cloning: Feasible Way to Save Species". blogs.umass.edu. December 2, 2015. Retrieved 2021-03-07.
  12. ^ Roush, Wade (February 17, 2006). "Genetic Savings and Clone: No Pet Project". MIT Technology Review.
  13. ^ BioArts International
  14. ^ Hawthorne, Lou (10 September 2009). "Six Reasons We're No Longer Cloning Dogs". Bioarts. Retrieved 23 March 2016. CS1 maint: discouraged parameter (link)
  15. ^ Arnold, Paul (14 September 2009). "Animal Cloning: Pet Cloning Controversy". Retrieved 23 March 2016. CS1 maint: discouraged parameter (link)
  16. ^ Agence France-Presse (September 20, 2009). "South Korea scientist wins dog cloning court battle". The China Post.
  17. ^ Dean, Josh (22 October 2014). "For $100,000, You Can Clone Your Dog". Bloomberg business. Retrieved 26 February 2016. CS1 maint: discouraged parameter (link)
  18. ^ a b Taylor, Diane (24 December 2015). "UK couple have dead dog cloned in South Korea". The Guardian. Retrieved 24 February 2016. CS1 maint: discouraged parameter (link)
  19. ^ Baer, Drake (8 September 2015). "This Korean lab has nearly perfected dog cloning, and that's just the start". Tech Insider, Innovation. Retrieved 27 February 2016. CS1 maint: discouraged parameter (link)
  20. ^ Zastrow, Mark (8 February 2016). "Inside the cloning factory that creates 500 new animals a day". New Scientist. Retrieved 23 February 2016. CS1 maint: discouraged parameter (link)
  21. ^ "British couple celebrate after birth of first cloned puppy of its kind". The Guardian. 26 December 2015. Retrieved 27 December 2015. CS1 maint: discouraged parameter (link)
  22. ^ "Chinese firm clones gene-edited dog in bid to treat cardiovascular disease". CNN. 2017-12-27. Retrieved 2020-07-09.
  23. ^ "His Cat's Death Left Him Heartbroken. So He Cloned It". The New York Times. 2019-09-04. Retrieved 2020-07-09.
  24. ^ Heðinsdóttir, K.; Kondrup, S.; Röcklinsberg, H.; Gjerris, M. (2018). "Can Friends be Copied? Ethical Aspects of Cloning Dogs as Companion Animals". Journal of Agricultural and Environmental Ethics. 31 (1): 17–29. doi:10.1007/s10806-018-9706-y. ISSN 1187-7863. S2CID 148814791.
  25. ^ a b Keefer, Carol (July 21, 2015). "Artificial cloning of domestic animals". Proceedings of the National Academy of Sciences. 112 (29): 8874–8. Bibcode:2015PNAS..112.8874K. doi:10.1073/pnas.1501718112. PMC 4517265. PMID 26195770.
  26. ^ a b Ibtisham, F.; Fahd Qadir, M. M.; Xiao, M.; An, L. (2017). "Animal cloning applications and issues". Russian Journal of Genetics. 53 (9): 965–971. doi:10.1134/s102279541709006x. ISSN 1022-7954. S2CID 19932688.
  27. ^ Heðinsdóttir, K.; Kondrup, S.; Röcklinsberg, H.; Gjerris, M. (2018-02-01). "Can Friends be Copied? Ethical Aspects of Cloning Dogs as Companion Animals". Journal of Agricultural and Environmental Ethics. 31 (1): 17–29. doi:10.1007/s10806-018-9706-y. ISSN 1573-322X. S2CID 148814791.
  28. ^ Shin, Taeyoung; Kraemer, Duane; Pryor, Jane; Liu, Ling; Rugila, James; Howe, Lisa; Buck, Sandra; Murphy, Keith; Lyons, Leslie; Westhusin, Mark (February 14, 2002). "A cat cloned by nuclear transplantation". Nature. 415 (6874): 859. doi:10.1038/nature723. PMID 11859353. S2CID 4431855.
  29. ^ Mott, Maryann (February 23, 2005). "Pet-Clone Sales Spur Call for Ban". National Geographic News. Retrieved April 12, 2018. CS1 maint: discouraged parameter (link)
  30. ^ "Cloned pets escape retail sales ban in California". dvm360 magazine. dvm360. July 1, 2005. Retrieved April 12, 2018. CS1 maint: discouraged parameter (link)