From: mk_thisisit
Introduction to Pioneering Research
Magdalena Żernicka-Goetz’s laboratory was the first to conduct research on human embryos up to day 14 of their development [00:00:03]. This breakthrough opened a new chapter in human development research [00:00:09]. Her work in embryology has been featured in top scientific journals such as Cell, Nature, and Science [00:01:15]. Science magazine named her discovery of a human embryo development phase the scientific breakthrough of 2016 [00:01:27].
Żernicka-Goetz has always been fascinated by the beginnings of life and existence [00:00:15]. For her, the most captivating aspect is the journey before birth, the “hidden, silent, and yet full of dramatic turns and miraculous transformations” that occurs in the mother’s body [00:00:31].
What Are Human Embryo Models?
Żernicka-Goetz’s laboratory created the first human embryo models based on stem cells [00:04:25]. These models are defined as living structures [00:04:47] that are embryo-like, meaning they are not true embryos but mimic their development to some extent [00:04:54]. They enable the reproduction of many key processes occurring in early human development, allowing scientists to study how cells interact, communicate, and influence each other [00:05:10].
Distinction from Natural Embryos and Synthetic Life
While research is conducted on natural mouse embryos, which are excellent models for understanding human development in the initial stages [00:05:47], human embryos are also used when necessary, originating from donors who choose not to use them for reproductive purposes from IVF clinics [00:06:08]. The development paths of mouse and human embryos diverge significantly after the first week, necessitating the study of human cells and other primates for a complete understanding [00:31:03].
These embryo models are not designed to develop into a complete human organism [00:09:47]. They cannot take root outside the mother’s body, and attempting such an experiment would violate ethical standards [00:10:00]. The term “synthetic embryo” is considered incorrect by Żernicka-Goetz, as these models are created from living stem cells to understand natural development, not to create artificial life [00:28:43].
The 14-Day Rule and Research Milestones
Żernicka-Goetz’s lab achieved the ability to develop human embryos in vitro for an additional 7 days beyond the typical 5-day limit, extending development up to 14 days [00:03:39]. This period, known as the “black box of embryonic development,” was previously inaccessible [00:03:10]. The 14-day rule was established many years ago as an ethical and experimental boundary [00:12:29]. Around day 14, the embryo begins forming new tissue types, and gastrulation, the “magical moment” when the body’s axis appears and cells arrange into future body structures, begins [00:14:35].
In 2023, the creation of human embryo models from stem cells was recognized as the “method of the year,” a decade after Żernicka-Goetz’s initial experiments [00:12:47]. Despite some media claims, no group, including Jakob Hanna’s team which bases its protocols on Żernicka-Goetz’s work, has exceeded the 14-day limit for human embryo models [00:29:35].
Technical Aspects of Creation
Embryo models are created using stem cells, which possess “almost unlimited development potential” [00:08:34]. These cells can transform into different cell types, interact, and create complex organ-like structures (organoids) [00:08:42]. Embryonic stem cells were first isolated in 1981, a discovery later awarded the Nobel Prize [00:07:02].
Żernicka-Goetz’s lab pioneered combining embryonic stem cells with two types of extraembryonic cells (those that form structures like the placenta) [00:07:51]. Published in Science in 2017, this method showed that combining these cell types can create a structure resembling an early embryo, allowing imitation of previously inaccessible aspects of embryo development [00:09:19].
Purpose and Significance of the Research
The primary purpose of these models is to enable developmental research, not to recreate a complete organism [00:10:54]. In a lab dish, researchers can observe developmental processes, analyze gene activation at specific stages, and study the effects of gene inactivity [00:10:28]. This allows for the discovery of fundamental mechanisms of “self-organizing processes” underlying the origin of life [00:10:48].
The research aims to understand the early stages of life because most pregnancies fail during these periods [00:17:49]. Approximately 60% of all pregnancies end within the first two weeks, often before a woman realizes she is pregnant [00:18:26]. By understanding these failures, particularly those linked to chromosomal changes [00:19:16], scientists hope to prevent losses and support life from its earliest moments [00:17:56].
Żernicka-Goetz believes that life is a dynamic, evolving process, even in its earliest forms [00:25:26]. She considers the moment of consciousness, feeling, and communication, which requires a nervous system, as the point where a being becomes “someone” rather than “something” [00:26:10].
Ethical Considerations and Misconceptions
All research on human embryos and stem cells must adhere to strict, well-founded regulations and undergo complex administrative processes [00:11:55]. Żernicka-Goetz’s team approaches all models, including mouse embryos, with “great respect” [00:11:30].
There is significant misunderstanding surrounding embryo research [00:41:04]. The public often confuses laboratory embryos with those developing in a woman’s body, or imagines scientists creating humans in test tubes [00:41:43]. However, the models lack the ability to continue development [00:41:48]. The research’s goal is to protect life by understanding early pregnancy failures, similar to how heart research aims to prevent heart attacks [00:42:04].
Strict prohibitions exist against manipulating human embryos for purposes inconsistent with knowledge, ethics, or human well-being, such as creating hybrid organisms intended for development outside the lab. The line between research and human engineering must be clearly drawn and carefully guarded [00:46:33].
Personal Motivation and Impact on Infertility
Magdalena Żernicka-Goetz’s research direction was profoundly influenced by her second pregnancy, when a prenatal test for her son, Simon, showed chromosomal abnormalities in some cells [00:19:37]. While studying mouse embryos to model her pregnancy, she discovered that if chromosomal changes occur, abnormal cells can be removed from the part of the embryo forming the baby’s body, but may be tolerated in the placenta [00:22:31]. This reveals the “extraordinary strength and plasticity of embryos,” where some can “save themselves” when things go wrong [00:23:01].
This discovery of embryos’ self-healing ability—eliminating abnormal cells to allow healthy ones to take over—is the opposite of what happens in cancer [00:36:33]. Applying this knowledge to develop treatments for unexplained infertility could be groundbreaking [00:37:01]. Unexplained infertility remains a significant problem, with a large percentage of pregnancies ending in miscarriage during the first two weeks [00:36:03].
The Future of Research
Żernicka-Goetz’s group continues to make new discoveries almost daily [00:37:26]. They believe the insights gained are foundational for “something truly profound” [00:38:47]. The embryonic models based on stem cells have opened a new chapter, allowing study of the earliest stages where key cell fate decisions are made [00:35:02].
Artificial intelligence (AI) plays a supporting role in the lab, used to analyze filmed embryo development and predict which embryos will develop successfully, though this is a small but evolving part of their research [00:32:00].
One recent discovery highlighted by Żernicka-Goetz, published last year, is that most of the human body originates from just one of the two cells at the two-cell stage after fertilization [00:49:07]. The second cell primarily contributes to the placenta, with only marginal involvement in the organism’s development [00:49:24]. This “early asymmetry” is still not fully understood [00:49:38].
Żernicka-Goetz emphasizes that the beauty of science lies in creating something bigger than oneself, with many laboratories now following this path, including those of her former students [00:35:37].