A team led by Magdalena Zernica-Goetz, from the University of Cambridge and the California Institute of Technology (Caltech), for the first time succeeded in creating synthetic human embryos from reprogrammed cells and kept them for 14 days of development, technical and technical. A legal limit that remained insurmountable. The advance was announced this Wednesday at the annual meeting of the International Society for Stem Cell Research in Boston, USA, and was previewed for the first time. By The GuardianIt allows us to explore for the first time a stage of human development that has remained a “black box”, but also raises ethical questions, since it is unexplored territory and not considered by regulators.
“We can create embryo-like models by reprogramming the cells [madre embrionarias]”, he claimed in the meeting Zernica-Goetz, who also noted that at this stage, the embryos have not yet developed either the heart or the brain, although they represent the precursor cells and the beginning of gametes. amnion, the membrane that covers it and which is later filled with amniotic fluid. Strictly speaking, it is not a human embryo, since it is formed from induced pluripotent cells and therefore without the use of sperm or egg, but it has very similar characteristics.
The announcement is part of a race with his rival and collaborator Jacob Hanna, a Palestinian researcher at the Weizmann Institute in Israel, with whom he announced the same achievement in late 2022, but in mice. In mice and other primate experiments, attempts to implant these embryos in the uterus have failed, but whether this is a technical problem or a biological barrier is unknown.
Zernica-Goetz and Hanna have previously argued that they are not real human embryos, but synthetic embryos or “embryos” that allow us to glimpse the first steps of development that have not been studied before because in most countries the law prohibits studies after 14 days. Its creation also has some very clear uses: understanding why many fertility treatments fail to implant and new efforts are needed, and pave the way for the creation of organoids on which to test drugs.
According to José Luis Cortes, the researcher who created the first human embryonic cell lines in Spain and among the first in the world, this advance demonstrates that science is both exciting and disturbing. “It’s exciting because it’s moving forward at a tremendous pace, with new discoveries almost daily, like this one about creating synthetic embryos. And it’s troubling because these discoveries are coming at a time when we still know almost nothing about the natural embryo. ” “This is a great advance because they are human embryos and this is the first time this has been achieved,” adds Luis Montoliu, a geneticist at the National Center for Biotechnology (CNB-CSIC). “We are witnessing a battle between two big names in embryology, who are collaborating and competing at the same time. Let’s see how Hannah responds, I can’t rule out that she put the batteries in and in a few days an article will appear that repeats it and goes a little further.
In any case, as Alfonso Martínez Arias, a researcher at the University of Cambridge and Pompeu Fabra, recalled in a statement. SMC Spain, it is convenient to wait for the results to be published and discussed. “There is no information beyond the articles in the press: neither a scientific article nor a preprint. Therefore, it is not possible to verify this work yet,” he assures us. “This could be an important scientific step, but again, we need to see the full report and data before making these claims.”
The questions raised by this new step in biotechnology primarily concern the status to be accorded to these synthetic embryos. “It’s not exactly like a zygote embryo, but it’s reconstructed, but it helps them answer a lot of questions about how this embryo develops so early that it’s considered a black box that we don’t have access to.” This,” explains Gemma Marfan, Professor of Genetics at the University of Barcelona (UB). “After 14 days, the neural tube begins to form, the first groove that is part of the nervous system. So far, it can be said that this embryo cannot be sentient because it has no neurons. But from that point you can enter into philosophical and ethical discussions,” he adds. “That’s why this progress can lead to ethical and legal problems in some countries, you have to go step by step and see where you can go.”
What status or protection should a synthetic embryo have? Is it the same as a human embryo?
– CNB-CSIC researcher
“What status or protection should a synthetic embryo have?” Is it the same as a human embryo?” – Montoliu wonders. “Would any mixture of human cells have the same protection if we’re not going to treat it as a germ and continue as an aggregate of cells?” The ethical challenge is exciting, and it’s also worrying if we miss them.”
“Unlike human embryos from IVF, where there is an established legal framework, there is currently no clear regulation governing stem cell-derived human embryo models,” says James Briscoe, team leader and deputy director of research at the Francis Crick Institute at SMC. “There is an urgent need for regulations that provide a framework for the creation and use of stem cell-derived human embryo models.
“There is much work to be done to establish the similarities and differences between synthetic embryos and embryos produced by the union of an egg and a sperm cell,” concludes Roger Sturmey, professor of reproductive medicine at Hull Medical School. “Due to the nature of this work, UK lawyers, ethicists and scientists are currently working to establish voluntary guidelines to ensure that synthetic embryo research is carried out responsibly.”
Source: El Diario