Blastoids are scientific models opening new ethical ways to investigate early pregnancy.
Because blastoids 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 with potential impact in family planning (e.g., fertility, contraception) and in the developmental origin of diseases (e.g., the origin of cardiovascular diseases) (see Rivron NC and Pera M, 2018). This model should contribute to improve human health and strongly alleviate the use of animals.
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? Because of the potential benefits, is there now an imperative to use them to investigate global health issues?
An international discussion is needed to help guide this research. We are thus discussing with ethicists, philosophers, lawyers, and international scientific societies, to propose 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 ban their use for reproductive purposes. We stated our ethic in a comment, which serves as a basis for further discussions (Rivron, Pera et al. 2018).
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.