Media claims say stem cell researchers generated synthetic human embryos. These embryos were produced from embryonic stem cells without sperm or ova.
This week’s International Society for Stem Cell Research annual meeting in Boston highlighted this finding, which might help scientists understand human development and genetic illnesses.
Professor Magdalena Żernicka-Goetz of Cambridge University and the California Institute of Technology revealed the findings. Reprogramming human embryonic stem cells produced these human-like embryos, Yernicka-Goetz told the gathering.
How does this affect science and ethics?
One stem cell creates each synthetic human embryo. Āernicka-Goetz explained how her team produced the synthetic embryos to “gastriculation,” a step slightly beyond the 14-day milestone for normal embryos.
The legal limit for lab-grown human embryos is 14 days.
If conceived in a human womb, this is the time between egg fertilization and uterine wall implantation.
For the first time, synthetic embryos have developed past this phase.
Scientists didn’t have the technology to keep embryos alive past 14 days, therefore the 14-day limitation was moral and practical.
The International Society for Stem Cell Research’s 2016 recommendations also said the 14-day restriction was morally reasonable since embryo cells began to specialize to become vital bodily systems including the stomach, brain, and lungs.
The International Society for Stem Cell Research’s amended 2021 guidelines suggest public debate to revisit the 14-day restriction and enable embryo research later in development.
Creating synthetic human-like embryos is a major development, according to Āernicka-Goetz’s study.
They also grow like human embryos.
The human-like embryos developed placenta and yolk sacs, but neither heart or brain, according to Āernicka-Goetz.
We know little about the placenta, despite its importance to mother and fetus.
These synthetic embryos might provide crucial placenta observation in a lab.
Moral dilemmas
Synthetic human-like embryos provide moral dilemmas as well as scientific opportunities.
One question is if their production eliminates human embryo usage.
Robin Lovell-Badge, head of stem cell biology and developmental genetics at the Francis Crick Institute in London, UK, said that if these human-like embryos can replicate human development in early pregnancy, we won’t need human embryos for study.
Two factors make this uncertain.
First, the embryos were produced from human embryonic stem cells, suggesting they still require human embryos. Hopefully Āernicka-Goetz’s research will illuminate this.
Second, these human-like embryos may not mirror human development.
Animal simulations show such synthetic embryos cannot grow into full live beings. Synthetic embryos perish shortly after being inserted into a female’s womb in mice and primates.
If human-like synthetic embryos cannot develop into whole human newborns or create vital bodily systems like a heart and brain, they may not be useful for studying human development.
Researchers want these embryos to study miscarriage and developmental abnormalities. This is crucial, but will synthetic embryos be “close enough” to human embryos to provide answers?
If these models require human embryos or these synthetic embryos cannot answer research issues, scientists may still utilize them.
Is it ethical?
The morality of using human embryos for research remains.
If human-like synthetic embryos may mature into full-grown humans, we must examine whether creating them for study is moral.
They may not develop beyond 14 days.
Because of their limitations, scientists may opt to remedy this problem. Scientists may modify synthetic embryos to prolong development. This would create a big moral dilemma.
We should consider if creating live human-like entities for study is ethical.