Ethical, legal, regulatory, and policy issues concerning embryoids: a systematic review of the literature

Abstract

Recent advances in methods to culture pluripotent stem cells to model human development have resulted in entities that increasingly have recapitulated advanced stages of early embryo development. These entities, referred to by numerous terms such as embryoids, are becoming more sophisticated and could resemble human embryos ever more closely as research progresses. This paper reports a systematic review of the ethical, legal, regulatory, and policy questions and concerns found in the literature concerning human embryoid research published from 2016 to 2022. We identified 56 papers that use 53 distinct names or terms to refer to embryoids and four broad categories of ethical, legal, regulatory, or policy considerations in the literature: research justifications/benefits, ethical significance or moral status, permissible use, and regulatory and oversight challenges. Analyzing the full range of issues is a critical step toward fostering more robust ethical, legal, and social implications research in this emerging area and toward developing appropriate oversight.

Stem Cell-Derived Organoids, Embryoids, and Embryos: Advances in Organismic Development In Vitro Force Us to Re-Focus on Ethical and Legal Aspects of Model Choice

“…It does not appear trivial anymore to define a border line between stem cell-derived embryoids and organoids. Embryoid constructs come in an astonishing variety, and also confusingly, many new terms have been proposed, like "artificial" or "synthetic embryos" [14], "synthetic human entities with embryo-like features, SHEEFs" [34], or "stembryos" [35], blastoids, gastruloids, and many others (for an overview see Table 3 in [36]). The recent ISSCR guidelines propose to distinguish between "integrated stem cell-based embryo models", which would possess derivatives of extraembryonic cell types (e.g., blastoids and ETX/iETX embryoids), and "non-integrated stem cell-based embryo models" (e.g., gastruloids which do not [15]).…”

Re-defining the human embryo

“…Thus, potentiality must refer to the embryo’s capacity to develop into a human being. If it cannot reach that stage, it should not be considered an embryo, but an embryoid (Iltis et al, 2023 ). Of course, our argument does not imply that an entity that has the capacity to develop to the foetal stage or even a foetus incapable of reaching viability has no moral significance.…”

“…Nevertheless, it is important to note that this does not suggest any form of equivalence between embryoids and actual human embryos. The proposed action would necessitate the creation of a distinct legal framework for embryoids, which is currently lacking in the majority of legislative systems, although certain regulations pertaining to specific scenarios do exist (Iltis et al, 2023 ).…”