The ethic of stem cell-based embryo models

Blastoids are scientific models to investigate early development. Because they are formed solely from stem cells, they alleviate the use of natural conceptus while opening unique possibilities for high-throughput screens and for finely modulating cellular (sub-)populations (e.g., genetically editing). These are the basis of biomedical discoveries. Blastoids thus allow to investigate in the lab previously untouchable scientific questions, while proposing ethical alternatives to the use of embryos for research (see Rivron NC and Pera M, 2018).


Blastoids are not considered as the legal equivalent of natural blastocysts. They are solely models that are used in the lab to answer scientific and biomedical questions. But they also question the current ethical status quo. What should their legal and ethical status be in the future as they are refined? Do the probable insights they provide outweigh possible ethical concerns?

We are contributing to an international discussion to help guide this research that involves ethicists, philosophers, lawyers, and international scientific societies, with the goal of proposing a framework of what should be and should not be done using blastoids and other later-stages embryo models (e.g., gastruloids). For example, we advice regulators to clearly ban their use for reproductive purposes. We stated our ethic in several publications that serve as a basis for further discussions.

Rivron N, Pera M, Rossant J, Martinez Arias A, Zernicka-Goetz M, Fu J, van den Brink S, Bredenoord A, Dondorp W, de Wert G, Hyun I, Munsie M, Isasi R. Debate ethics of embryo models from stem cells. Nature. 2018 Dec;564(7735):183-185. doi: 10.1038/d41586-018-07663-9.

©2017 by Nicolas Rivron Lab.