Two research teams from The Rockefeller University and the University of Cambridge have managed to keep human embryos alive almost two full weeks, which allowed them to provide the first hints of what they describe as the most mysterious stage of human life.

Prior to these studies, published Wednesday in the journal Nature and Nature Biology, they had only been able to study human embryos as a culture in a lab dish until the seventh day, when they had to implant them into the mother’s uterus so they could develop further, according to a report by Reuters.

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There are internationally accepted guidelines for scientific experiments with human embryos before they are implanted into the mother’s uterus: A 14-day mark is established. Credit: futureoflife

Both research teams have shown the amazing ability cells designed to eventually form the human body have to self-organize into the basic structure of a post-implantation embryo.

Researchers conducted almost hour by hour observations of human embryo development by using a culture method previously developed by Cambridge University’s Magdalena Zernicka-Goetz for work with mice embryos. They replicated the process of normal womb implantation within a petri dish, surpassing the one week mark.

“This is the most enigmatic and mysterious stage of human development,” said Zernicka-Goetz, study co-author. “It is a time when the basic body shape is determined.”

Marta Shahbazi, a researcher at Britain’s University of Cambridge involved in one of the studies, explained that their system allowed them to reveal an incredible self-organizing capacity previously unknown even though embryo development was a very complex process that could not be fully reproduced in a lab.

Ethical implications

The fact that scientists have doubled life expectancy for human embryos in petri dishes has raised ethical concerns. The 14-day international rule is based on the so-called primitive streak, which occurs on the 15th day and consists of the symmetry of the human body starting to take shape.

The embryo can split into identical multiples before getting to this point and the streak’s look is thought to be an approximation for an embryo’s identity as an individual, according to a report by The Washington Post.

Study authors say the fact that they have been able to break the rule does not mean the guidelines should be immediately changed. They warn that changing these rules could cause a moral controversy which could threaten relevant stem cell research and affect the improvement of in-vitro fertilization techniques.

Still, they believe the studies could help develop important scientific achievements given their potential to allow the research on early human development with unprecedented accuracy.

Source: Washington Post