Formed without eggs or sperm, these stem-cell-derived models mimic key phases of early human embryogenesis, including the appearance of hematopoietic progenitors that eventually form blood and immune cells.  

The discovery could reshape how scientists study the origins of blood development and genetic disease, providing a controllable model to investigate processes that normally occur in the womb.   

It also offers new possibilities for testing drugs, studying miscarriage and developmental disorders, and exploring the creation of patient-specific blood cells for therapy. Because the method does not rely on donated embryos, it could also ease some ethical and regulatory constraints surrounding human developmental research.  

Although the models cannot form a foetus and are not considered true embryos, they represent a major advance in the ability to observe and manipulate early human biology. Future research will aim to verify whether the blood-like cells behave as genuine hematopoietic stem cells and whether this system could one day inform regenerative or transfusion medicine.