Ectogenesis

Ectogenesis (from the Greek ἐκτός, "outside", and genesis) is the growth of an organism in an artificial environment, 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. The term was coined by British scientist J. B. S. Haldane in 1924.

Human embryos and fetuses

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 LGBTQ, infertile, disabled, or single men and women could have genetic offspring without the use of surrogate pregnancy, and allow women to have children without going through the pregnancy cycle.

Synthetic embryo

thumb|Post-gastrulation synthetic embryos generated ex utero from mouse naive embryonic stem cell

In 2022, Jacob Hanna and his team at the Weizmann Institute of Science created early "embryo-like structures'" from mice stem cells. 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. created a synthetic mouse 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.

The embryos grew in vitro and subsequently ex utero in an artificial womb published the year before by the Hanna team in Nature, 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", The term "synthetic embryo" in the title of the second study was later changed to the alternative term "embryo model". using naïve ES cells expanded in special naive conditions developed by the same team in 2021. It also uses reprogrammed genetically unmodified naïve stem cells to become any type of body tissue. Chemicals were used to coax these stem cells into becoming four types of cells found in the earliest stages of the human embryo. The mixture began assembling itself into a structure that resembles, but is not identical to, a human embryo. The embryo model (termed and abbreviated as SEM) mimics all the key structures; like that of a "textbook image" of a human day-14 embryo.

There are theoretical concerns that children who develop in an artificial uterus may lack "some essential bond with their mothers that other children have", 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."

Arathi Prasad argues in her column in The Guardian in her article "How artificial wombs will change our ideas of gender, family and equality" that "[i]t will ... give men an essential tool to have a child entirely without a woman, should they choose. It will ask us to question concepts of gender and parenthood." She furthermore argues for the benefits for same-sex couples, saying: "It might also mean that the divide between mother and father can be dispensed with: a womb outside a woman’s body would serve women, trans women and male same-sex couples equally without prejudice." It could even be a solution for women with absolute uterine infertility.

Human embryos and fetuses

Synthetic embryo

See also

References

Further reading