Scientists have created synthetic mouse embryos with developed brains – MIT Technology Review

The stem-cell-derived embryos could shed new light on the earliest stages of human pregnancy.
Mouse embryos recently generated from stem cells in a lab show more brain development than any synthetic mouse embryos created previously.  
While other researchers had created mouse embryos from stem cells, none had reached the point where the entire brain, including the anterior portion at the front, began to develop, according to the researchers from the University of Cambridge and the California Institute of Technology.
With plans to create realistic synthetic embryos, grown in jars, Renewal Bio is on a journey to the horizon of science and ethics.
The findings, described in a paper in Nature today, could help scientists learn more about how human embryos develop and provide insights into diseases, as well as providing an alternative to animals for testing.
The new model embryos, which bypass the need for sperm or egg cells, were developed in the lab alongside natural mouse embryos. They mirrored the same stages of development up to eight and a half days after fertilization, developing beating hearts and other foundations of organs, including the neural tubes that eventually turn into the brain and spinal cord.
“I think it’s a major advance,” says Leonardo Beccari from the Center for Molecular Biology Severo Ochoa, in Madrid, who was not involved in the research.
Studying how mouse stem cells interact at this point in development could also provide valuable insight into why human pregnancies fail during the earliest stages, and how to prevent that from happening.
“This is really the first demonstration of the forebrain in any models of embryonic development, and that’s been a holy grail for the field,” says David Glover, research professor of biology and biological engineering at Caltech, a coauthor of the report.
Stem cells are able to develop into specialized cells, including muscle, brain, or blood cells. The synthetic embryos were made of three types of cells from mice: embryonic stem cells, which form the body; trophoblast stem cells, which develop into the placenta; and extraembryonic endoderm stem cells, which help to form the egg sac. 
The embryos were developed in an artificial incubator created by Jacob Hanna of the Weizmann Institute in Israel, who recently kept realistic-looking mouse embryos growing in a mechanical womb for several days until they developed beating hearts, flowing blood, and cranial folds. Hanna is also a coauthor of the new study.
By mimicking the natural processes of how a mouse embryo would form inside a uterus, the researchers were able to guide the cells into interacting with each other, causing them to self-organize into structures that progressed through developmental stages to the point where they had beating hearts and foundations for the entire brain.  
The team also removed a gene called Pax6, which is essential for the formation of the central nervous system and brain and eye development, to test how the model embryos would react. The synthetic models went on to exhibit the same known defects in brain development as a natural animal carrying the mutation. Next, the researchers are interested in knocking out genes with unknown functions in brain development, which could shed light on the cause of some defects.
Researchers are growing embryos outside the womb for longer than has ever been possible.
Human model embryos could play a significant role in helping scientists understand why certain gene mutations happen, and they could help in testing potential treatment for a range of disorders.
While the synthetic embryos were able to reach the same developmental stage as the natural mouse embryos, they stopped growing around halfway through a typical mouse pregnancy period of 19 to 20 days, and they failed to develop past the eighth day. Hanna’s lab experienced the same problem, and the researchers don’t yet understand why. 
The researchers are already working on a synthetic placenta-like structure that they hope will allow the synthetic embryos to continue growing one or two days past the eight-day mark. 
Pushing past that point will be very important for developing new drugs and establishing which drugs are compatible with natural development, says Magdalena Zernicka-Goetz, a professor in mammalian development and stem cell biology in Cambridge’s Department of Physiology, Development, and Neuroscience, who led the research. Her research into artificial embryos was named one of MIT Technology Review’s 10 breakthrough technologies in 2018.
With plans to create realistic synthetic embryos, grown in jars, Renewal Bio is on a journey to the horizon of science and ethics.
A scientist went looking for genes that cause cannabinoid hyperemesis syndrome. But a public spat with a cannabis influencer who suffers from the disease may have derailed his research.
In a first, a patient in New Zealand has undergone gene-editing to lower their cholesterol. It could be the beginning of new era in disease prevention.
There’s a robust molecular language being spoken between your muscles and your brain.
Discover special offers, top stories, upcoming events, and more.
Thank you for submitting your email!
It looks like something went wrong.
We’re having trouble saving your preferences. Try refreshing this page and updating them one more time. If you continue to get this message, reach out to us at with a list of newsletters you’d like to receive.
Our in-depth reporting reveals what’s going on now to prepare you for what’s coming next.
Subscribe to support our journalism.
© 2022 MIT Technology Review


Leave a Reply

Next Post

10x Genomics lawsuit says startup copied gene-analysis technology - Reuters

Sun Aug 28 , 2022
REUTERS/Thomas Peter(Reuters) – Gene-sequencing company 10x Genomics Inc sued startup Parse Biosciences Inc in Delaware federal court Wednesday, alleging its gene-analysis kits infringe patents related to 10x's Chromium platform.Pleasanton, California-based 10x said in the lawsuit that its competitor has "made clear that it intends nothing less than to copy 10x's […]
%d bloggers like this: