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Related Experiment Video
Updated: Mar 27, 2026

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Using Mouse Oocytes to Assess Human Gene Function During Meiosis I
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Morphogen Gradients as Drivers of Mosaicism During Early Human Development.
Sergio P Acebrón1,2,3, Janina Hattemer3, Tobias Rausch4
1University of the Basque Country (UPV/EHU), Leioa, Spain.
Summary
Signalling gradients in early human embryos can cause chromosome errors, potentially linking to miscarriage and developmental disorders. This study explores how these pathways impact genome and chromosomal mosaicism.
Area of Science:
- Developmental Biology
- Genetics
- Stem Cell Biology
Background:
- WNT, BMP, FGF, and Nodal signalling pathways are crucial for early human embryonic development, including epiblast transitions and gastrulation.
- These signalling pathways have been recently implicated in controlling chromosome replication and segregation fidelity in human pluripotent stem cells.
- Aneuploidy in early embryos is a leading cause of human miscarriage and is linked to neurodevelopmental disorders.
Purpose of the Study:
- To hypothesize how the antero-posterior (A-P) signalling gradient generates genome and chromosomal mosaicism in human embryos.
- To explore the potential links between A-P signalling, mosaicism, and human infertility.
- To investigate the connection between A-P signalling, mosaicism, and lineage-specific developmental disorders.
Main Methods:
- The study proposes a hypothesis based on existing literature regarding signalling pathways and chromosomal integrity.
- It integrates knowledge of WNT, BMP, FGF, and Nodal signalling antagonists (DKK1, Cerberus, LEFTY2, Noggin, Chordin).
- The hypothesis focuses on the induction of DNA replication stress and damage during S-phase.
Main Results:
- WNT and BMP antagonists associated with embryo anteriorization induce DNA replication stress and damage.
- This damage leads to ultra-fine-bridges and whole-chromosome mis segregation during mitosis.
- The antero-posterior (A-P) signalling gradient is hypothesized to generate overlapping patterns of genome and chromosomal mosaicism.
Conclusions:
- The A-P signalling gradient may generate mosaicism, contributing to aneuploidy in human embryos.
- This mosaicism could be linked to the high incidence of human miscarriage.
- Potential connections to human infertility and lineage-specific developmental disorders are proposed.

