World news – Scientists create model embryos and raise ethical questions


Australian researchers have “modeled” human embryos from the skin cells of the arm of an adult. This is a world’s first scientific breakthrough that raises important ethical questions.

The model embryos, made in a laboratory by researchers at Monash University in Melbourne, do not use eggs or sperm, but ordinary cells that have been reprogrammed to to replicate the first days of human life.

When placed in a dish, the model embryos attach – much like embryos in the womb – and begin to develop.

However, they are not identical With natural embryos, some key features are missing and they contain cells that are normally invisible.

On this basis, and with data from animals, scientists do not believe that they can fully develop – and so are vehemently opposed to their work as « artificial embryos ».

« I don’t feel as though I created life, » said Professor Jose Polo, head of the Monash team who made the discovery and was published in Nature on Thursday.

“Basically, we’ve just created a good model. I am 100 percent sure that based on all the evidence available, they can only model the very early stages of development and therefore cannot develop into a human. “

The researchers are aware of the most important ethical questions that arise from their work – for example, whether a model embryo should enjoy the same protection as a real one – and so far they have not grown beyond the 11-day mark Let.

You and other experts say there needs to be a community conversation about the status of these new creations, what ethical research can be done on them, and how far they can go.

The Catholic Church for example, believes that life begins with fertilization. Professor Polo’s model embryos, however, do not require fertilization.

« How religious leaders will take this I don’t know to be honest, » said Professor Polo. “We have to remember that this is a model. They have no development potential. You can’t make a baby. We need to have the discussion. How far can we use these models to model biology? “

The model embryos that scientists call iBlastoids provide an opportunity to study the earliest days of human development – currently difficult because of ethical constraints on studying natural embryos.

They could be used to determine the causes for infertility, miscarriages, birth defects, and the reasons why embryos sometimes cannot be implanted in the womb.

« These studies show two remarkable things: that the earliest stages of human development do not need an egg and that only with Skin cells, some genes, and the right chemical conditions, « said Jason Limnios, a researcher at the Clem Jones Center for Regenerative Medicine at Bond University who was not involved in the research.

Those created by Professor Polo’s lab Cells are very similar to blastocysts, the name given to an egg in the days after it is fertilized with sperm rde, but before it is implanted on the wall of the uterus.

Professor Polo’s team worked with skin cells and manipulated their genetic instructions to turn them into stem cells – cells that can become any other cell type with a little nudge .

But about 2 percent of the cells were not behaving properly. Instead of turning into stem cells, they turned on a collection of unexpected genes – the same ones an early embryo would turn on in the days after being fertilized by a sperm.

Spread out on a flat Petri dish, these strange cells just sat there . Professor Polo’s team wondered what the cells in close proximity to each other could do and placed them in a small jar shaped like an upside-down pyramid. The cells squeezed together below.

Five or six days later, Professor Polo’s team returned to the jars and found that the cells were no longer just there. Instead, they had assembled themselves into tiny spheres. When they examined these spheres, they found that each had a second, smaller sphere – the primitive endoderm and embryonic stem cells that would eventually become human in a real embryo.

Professor Polo suddenly realized, what he had done and stopped the experiment. He contacted the Ethics Committee of Monash University and the Federal Government’s Embryo Research Licensing Committee.

“It took months for you to take care of this. Finally, they said they want us to stop creating them until we decide how to go about it, « said Professor Polo.

The regulator said Wednesday that it is using cells as » the definition of a human embryo in the Law on Inclusion of Human Embryos of 2002 “and would regulate them as such – which means that research can continue but the model embryos are not developed further than 14 days for the time being.

Compared to human embryos in a similar At the 1st stage, the model embryos share many of the same cells. When tested with a standard IVF Embryo Quality Score, the model embryos were rated « good. »

But the researchers and independent scientists try to emphasize that they do not believe they have created life, nor viable embryos.

« I don’t think their models of embryonic development are or ever will be replicas, » said Megan Munsie, Professor of Ethics, Education and Policy in Stem Cell Science at the University of Melbourne.

« The biology is so complex that it would be extremely challenging, and that is what we see in animal work. « 

However, an editorial by the leading developmental biology experts, Yi Zheng and Jianping Fu, co-published with the research in Nature, indicates that these problems are likely to be resolved soon.

« For many people, studying human blastoids will be less ethical than studying natural human ones fro blastocysts. However, others might consider research on human blastoids as a way of developing human embryos. This will inevitably lead to bioethical issues. What should be the ethical status of human blastoids and how should they be regulated? “

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