The experiment stopped after the 14th day, but at the same time the issue of continuation also arose, which would necessarily raise ethical, if not legal, dilemmas.

Scientists at the Weizmann Institute in Israel managed to create an embryonic model from stem cells, without sperm, egg or uterus, he writes. BBC. The entity created in this way is practically an exact copy of a 14-day-old human embryo that even released hormones that produced a positive pregnancy test in the laboratory.

Dramatic changes occur in the first weeks after the egg is fertilized by a sperm, when a mishmash of cells develops into the entity that will later be identified on an ultrasound scan. This period is the source of quite a few miscarriages and birth defects, but we still hardly know anything about it.

On the one hand, this is because embryo research is overburdened legally, ethically and technically, but at the same time, research that can now create an exact copy of embryos could serve as a solution to this problem.

According to a study published in the journal Nature, the Israeli research team succeeded in creating a complete embryonic model that contains all the characteristics of an early embryo. Instead of sperm and eggs, they used naïve embryonic stem cells, which have been reprogrammed to be able to become any type of tissue in the body. Then, with the help of chemicals, the stem cells were divided into four different groups of cells found in early embryos:

  • Highly cylindrical epithelial cells, i.e. future embryo
  • Trophoblast, which is the outermost layer of the fetal membrane and later forms the placenta
  • The tiny squamous cells that make up the extra-embryonic tissue will become the fetal membrane
  • Germ plate cells outside the embryo

The scientists mixed 120 cells of the aforementioned species in the correct proportions, then stepped back and waited. Roughly one percent of the mixture began to spontaneously aggregate into a structure reminiscent of a human embryo.

The models were allowed to develop for 14 days, as this is the legal upper limit for embryo research in most countries.

The meaning of the whole experiment is that embryo models could, in principle, be able to show how different types of cells are formed, and during the process, the recovery of organs can be observed and genetically inherited diseases can be better understood. .

This research has already shown that only those parts of the fetus that can be covered by early placental initiation develop. The research could also aid in the effectiveness of IVF by observing why certain embryos do not grow larger while others do, and it could also test the effects of different medications.

Meanwhile, the failure rate of 99 percent is something worth working towards in order to achieve serious results with embryo models.

Especially since research also stretches very serious moral and ethical limits, if only because the goal would obviously be to be able to continue working after the fourteenth day. This would not be illegal in the UK, since a fetus and embryo model do not legally fall under the same category, but it is quite certain that such experiments would be divisive.

The researchers also stressed that it would be unethical, illegal and actually impossible to achieve pregnancy with these embryonic models.


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