Various genetic diseases and congenital defects in humans have been determined in the early stages of embryonic development. However, due to limitations in research ethics and technological means, it is difficult for scientists to directly obtain early human embryos for research, and in vitro research on human embryos cannot exceed the 14 day ethical limit. So what should we do? For this reason, scientists have come up with an alternative research model: non human primate embryos. The Chinese and American research team led by Chinese scientists has established for the first time a 3D long-term system that can support the long-term development of crab eating monkey embryos in vitro until 25 days after fertilization. Based on this system, core events and lineage characteristics in the early neural development process of primate embryos have been explored. The results were recently published online in the international academic journal Cell. Establishing a culture system that can support in vitro development of non human primate embryos is not an easy task. Wang Hongmei, a researcher at the Institute of Zoology, Chinese Academy of Sciences/Beijing Institute of Stem Cell and regenerative medicine, is the final corresponding author of this study. She introduced that in 2019, the team had achieved in vitro cultivation of non human primate embryos until the 20th day after fertilization, and studied the early gastrulation characteristics of primate embryos. In this recent study, "we fully compared different culture systems and optimized one of them to construct a system that can extend the in vitro development of crab eating monkey embryos to the 25th day, and named it the '3D long-term culture system'. Wang Hongmei said, "Based on this system, we can finally delve deeper into what 'stories' embryonic development went through from day 20 to day 25." In this system, researchers explored the early neural embryonic development process in primates. We know that human embryos begin gastrulation on the 14th day - a milestone event in early embryonic development. During this process, embryonic cells undergo large-scale differentiation, migration, and rearrangement, forming the outer, middle, and inner germ layers and body axis. On the basis of the development of the three germ layers, the embryo further begins early multi organ development. Based on the 25 day culture, researchers revealed the morphology, cell composition, transcriptome, DNA methylation, chromatin accessibility and other characteristics of primate embryos from the middle and late gastral movement to the early neuroembryonic development stage, laying the foundation for further revealing the mystery of human embryos. International peer reviews suggest that this study further fills the gap in the field of primate embryo development from late gastrulation to early organ development, based on existing in vivo research. It provides a reference system for in vitro cultivation of primate embryos and in vitro cultivation of "embryonic like" structures based on stem cells, and provides a deeper understanding of the mechanisms of human early embryonic development, And the pathological research of early embryo dysplasia related diseases provides a technical platform. (Outlook New Era Network)