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Ectogenesis

From Wikipedia, the free encyclopedia

Ectogenesis (from the Greek ἐκτός, "outside", and genesis) is the growth of an organism in an artificial environment,[1] outside the body in which it would normally be found, such as the growth of an embryo or fetus outside the mother's body, or the growth of bacteria outside the body of a host.[2] The term was coined by British scientist J. B. S. Haldane in 1924.[3][4]

Human embryos and fetuses

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Ectogenesis of human embryos and fetuses would require an artificial uterus. An artificial uterus would have to be supplied with nutrients and oxygen from some source to nurture the fetus, as well as dispose of waste material. There would likely be a need for an interface between such a supplier, filling this function of the placenta. As a replacement organ, an artificial uterus could be used to assist women with damaged, diseased or removed uteri to allow the fetus to be conceived to term. It also has the potential to move the threshold of fetal viability to a much earlier stage of pregnancy. This would have implications for the ongoing controversy regarding human reproductive rights. Ectogenesis could also be a means by which homosexual, impotent, disabled, and single men and women could have genetic offspring without the use of surrogate pregnancy or a sperm donor, and allow women to have children without going through the pregnancy cycle.[5]

Synthetic embryo

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Post-gastrulation synthetic embryos generated ex utero from mouse naive embryonic stem cells[6]

In 2022, Jacob Hanna and his team at the Weizmann Institute of Science created early "embryo-like structures'" from mice stem cells.[7][8] Their research was published by Cell on 1 August 2022. The world's first synthetic embryo does not require sperm, eggs, nor fertilization, and were grown from only embryonic stem cells (ESCs) or also from stem cells other than ESCs.[8] The structure had an intestinal tract, early brain, and a beating heart and a placenta with a yolk sac around the embryo.[8] The researchers said it could lead to better understanding of organ and tissue development, new sources of cells and tissues for human transplantation,[8] although human synthetic embryos are a long ways off.[8]

Also in August 2022, a study described how University of Cambridge, alongside the same Weizmann Institute of Science scientists,[6] created a synthetic embryo with a brain and a beating heart by using stem cells (also some stem cells other than ESCs). No human eggs nor sperm were used. They showed natural-like development and some survived until day 8.5 where early organogenesis, including formation of foundations of a brain, occurs. Scientists hope it can be used to create synthetic human organs for transplantation.[9][10]

The embryos grew in vitro and subsequently ex utero in an artificial womb published the year before by the Hanna team in Nature,[11] and was used in both studies. Potential applications include "uncovering the role of different genes in birth defects or developmental disorders", gaining "direct insight into the origins of a new life", "understand[ing] why some pregnancies fail",[10] and developing sources "of organs and tissues for people who need them".[12][13][14] The term "synthetic embryo" in the title of the second study was later changed to the alternative term "embryo model".[9]

On 6 September 2023, Nature published research that the Weizmann Institute team created the first complete human day 14 post-implantation embryo models,[15] using naïve ES cells expanded in special naive conditions developed by the same team in 2021.[16] It also uses reprogrammed genetically unmodified naïve stem cells to become any type of body tissue.[15][17] The embryo model (termed and abbreviated as SEM) mimics all the key structures like a "textbook image" of a human day-14 embryo.[15][17]

Bioethical considerations

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The development of artificial uteri and ectogenesis raises a few bioethical and legal considerations, and also has important implications for reproductive rights and the abortion debate.[5]

Artificial uteri may expand the range of fetal viability, raising questions about the role that fetal viability plays within abortion law.[5] For example, within severance theory, abortion rights only include the right to remove the fetus, and do not always extend to the termination of the fetus.[5] In the abortion debate, the death of the fetus has historically been considered an unavoidable side effect rather than the primary goal of an abortion.[5] If transferring the fetus from a woman's womb to an artificial uterus becomes possible, then the choice to terminate a pregnancy in this way could result in a living child.[18][19][20] Thus, the pregnancy could be aborted at any point, which respects the woman's right to bodily autonomy, without impinging on the moral status of the embryo or fetus.[5]

There are theoretical concerns that children who develop in an artificial uterus may lack "some essential bond with their mothers that other children have",[21] a secondary issue to woman's rights over their own body. In the 1970 book The Dialectic of Sex, feminist Shulamith Firestone wrote that differences in biological reproductive roles are a source of gender inequality. Firestone singled out pregnancy and childbirth, making the argument that an artificial womb would free "women from the tyranny of their reproductive biology."[22][23]

See also

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References

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  1. ^ "Ectogenesis". Webster's New World College Dictionary. Wiley Publishing. 2010. Archived from the original on 4 November 2023. Retrieved 7 May 2024.
  2. ^ "Ectogenesis". Collins English Dictionary (Complete and Unabridged 11th ed.). 2011. Archived from the original on 7 May 2024. Retrieved 7 May 2024.
  3. ^ Istvan, Zoltan (4 August 2014). "Artificial Wombs Are Coming, but the Controversy Is Already Here". Motherboard. Archived from the original on 4 April 2024. Retrieved 7 May 2024.
  4. ^ James, David N. (1 January 1987). "Ectogenesis: a reply to Singer and Wells". Bioethics. 1 (1): 80–99. doi:10.1111/j.1467-8519.1987.tb00006.x. PMID 11649763. Archived from the original on 4 November 2023.
  5. ^ a b c d e f Moran, Rosalind (3 April 2023). "Artificial Wombs Will Change Abortion Rights Forever". Wired. ISSN 1059-1028. Archived from the original on 16 April 2024. Retrieved 7 May 2024.
  6. ^ a b Tarazi, Shadi; Aguilera-Castrejon, Alejandro; Joubran, Carine; Ghanem, Nadir; Ashouokhi, Shahd; Roncato, Francesco; Wildschutz, Emilie; Haddad, Montaser; Oldak, Bernardo; Gomez-Cesar, Elidet; Livnat, Nir; Viukov, Sergey; Lokshtanov, Dmitry; Naveh-Tassa, Segev; Rose, Max; Hanna, Suhair; Raanan, Calanit; Brenner, Ori; Kedmi, Merav; Keren-Shaul, Hadas; Lapidot, Tsvee; Maza, Itay; Novershtern, Noa; Hanna, Jacob H. (1 September 2022). "Post-gastrulation synthetic embryos generated ex utero from mouse naive ESCs". Cell. 185 (18): 3290–3306.e25. doi:10.1016/j.cell.2022.07.028. ISSN 0092-8674. PMC 9439721. PMID 35988542.
  7. ^ Tarazi, Shadi; Aguilera-Castrejon, Alejandro; Joubran, Carine; Ghanem, Nadir; Ashouokhi, Shahd; Roncato, Francesco; Wildschutz, Emilie; Haddad, Montaser; Oldak, Bernardo; Gomez-Cesar, Elidet; Livnat, Nir; Viukov, Sergey; Lokshtanov, Dmitry; Naveh-Tassa, Segev; Rose, Max (1 August 2022). "Post-gastrulation synthetic embryos generated ex utero from mouse naive ESCs". Cell. 185 (18): 3290–3306.e25. doi:10.1016/j.cell.2022.07.028. ISSN 1097-4172. PMC 9439721. PMID 35988542.
  8. ^ a b c d e Sample, Ian (3 August 2022). "Scientists create world's first 'synthetic embryos'". The Guardian. ISSN 1756-3224. Archived from the original on 3 August 2022. Retrieved 7 May 2024.
  9. ^ a b Amadei, Gianluca; Handford, Charlotte E.; Qiu, Chengxiang; De Jonghe, Joachim; Greenfeld, Hannah; Tran, Martin; Martin, Beth K.; Chen, Dong-Yuan; Aguilera-Castrejon, Alejandro; Hanna, Jacob H.; Elowitz, Michael B.; Hollfelder, Florian; Shendure, Jay; Glover, David M.; Zernicka-Goetz, Magdalena (25 August 2022). "Embryo model completes gastrulation to neurulation and organogenesis". Nature. 610 (7930): 143–153. doi:10.1038/s41586-022-05246-3. ISSN 1476-4687. PMC 9534772. PMID 36007540. S2CID 251843659.
  10. ^ a b Brackley, Paul (1 September 2022). "Synthetic embryo with brain and beating heart created by University of Cambridge scientists". Cambridge Independent. Archived from the original on 17 September 2022. Retrieved 7 May 2024.
  11. ^ Aguilera-Castrejon, Alejandro; Oldak, Bernardo; Shani, Tom; Ghanem, Nadir; Itzkovich, Chen; Slomovich, Sharon; Tarazi, Shadi; Bayerl, Jonathan; Chugaeva, Valeriya; Ayyash, Muneef; Ashouokhi, Shahd; Sheban, Daoud; Livnat, Nir; Lasman, Lior; Viukov, Sergey (May 2021). "Ex utero mouse embryogenesis from pre-gastrulation to late organogenesis". Nature. 593 (7857): 119–124. doi:10.1038/s41586-021-03416-3. ISSN 1476-4687. PMID 33731940. Archived from the original on 13 February 2024. Retrieved 7 May 2024.
  12. ^ Willyard, Cassandra (25 August 2022). "Mouse embryos grown without eggs or sperm: why, and what's next?". Nature. 609 (7926): 230–231. Bibcode:2022Natur.609..230W. doi:10.1038/d41586-022-02334-2. PMID 36008716. S2CID 251843735.
  13. ^ "Synthetischer Embryo entwickelt Organe" [Synthetic embryo develops organs]. Science Media Center Germany (in German). 25 August 2022. Archived from the original on 5 December 2023. Retrieved 7 May 2024.
  14. ^ Holcombe, Madeline (5 September 2022). "A synthetic embryo, made without sperm or egg, could lead to infertility treatments". CNN. Archived from the original on 16 November 2023. Retrieved 7 May 2024.
  15. ^ a b c Oldak, Bernardo; Wildschutz, Emilie; Bondarenko, Vladyslav; Comar, Mehmet-Yunus; Zhao, Cheng; Aguilera-Castrejon, Alejandro; Tarazi, Shadi; Viukov, Sergey; Pham, Thi Xuan Ai; Ashouokhi, Shahd; Lokshtanov, Dmitry; Roncato, Francesco; Ariel, Eitan; Rose, Max; Livnat, Nir (6 September 2023). "Complete human day 14 post-implantation embryo models from naive ES cells". Nature. 622 (7983): 562–573. doi:10.1038/s41586-023-06604-5. ISSN 1476-4687. PMC 10584686. PMID 37673118. Archived from the original on 6 September 2023. Retrieved 7 May 2024.
  16. ^ Bayerl, Jonathan; Ayyash, Muneef; Shani, Tom; Manor, Yair Shlomo; Gafni, Ohad; Massarwa, Rada; Kalma, Yael; Aguilera-Castrejon, Alejandro; Zerbib, Mirie; Amir, Hadar; Sheban, Daoud; Geula, Shay; Mor, Nofar; Weinberger, Leehee; Naveh Tassa, Segev (2 September 2021). "Principles of signaling pathway modulation for enhancing human naive pluripotency induction". Cell Stem Cell. 28 (9): 1549–1565.e12. doi:10.1016/j.stem.2021.04.001. ISSN 1934-5909. PMC 8423434. PMID 33915080.
  17. ^ a b Gallagher, James (6 September 2023). "Scientists grow whole model of human embryo, without sperm or egg". BBC News. Archived from the original on 7 May 2024. Retrieved 7 May 2024.
  18. ^ Randall, Vernellia; Randall, Tshaka C. (22 March 2008). "Built in Obsolescence: The Coming End to the Abortion Debate". SSRN Electronic Journal. doi:10.2139/ssrn.1112367. ISSN 1556-5068. S2CID 57105464. Archived from the original on 5 October 2009. Retrieved 7 May 2024.
  19. ^ Chessen, Matt (2 March 2013). "Artificial Wombs Could Outlaw Abortion". Mattlesnake.com. Archived from the original on 4 December 2013. Retrieved 7 May 2024.
  20. ^ Mathison, Eric; Davis, Jeremy (9 February 2017). "Is There a Right to the Death of the Foetus?". Bioethics. 31 (4): 313–320. doi:10.1111/bioe.12331. ISSN 0269-9702. PMID 28182294. S2CID 3808881. Archived (PDF) from the original on 28 January 2024. Retrieved 7 May 2024.{{cite journal}}: CS1 maint: date and year (link)
  21. ^ Smajdor, Anna (Summer 2007). "The Moral Imperative for Ectogenesis" (PDF). Cambridge Quarterly of Healthcare Ethics. 16 (3): 336–45. doi:10.1017/s0963180107070405. PMID 17695628. S2CID 36754378. Archived from the original (PDF) on 11 September 2013. Retrieved 7 May 2024.
  22. ^ Chemaly, Soraya (23 February 2012). "What Do Artificial Wombs Mean for Women?". RH Reality Check. Archived from the original on 19 November 2023. Retrieved 7 May 2024.
  23. ^ Rosen, Christine (2003). "Why Not Artificial Wombs?" (PDF). The New Atlantis (Fall 2003): 67–76. ISSN 1555-5569. PMID 15586953. Archived (PDF) from the original on 26 November 2023. Retrieved 7 May 2024.

Further reading

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