Observation of two separate bipolar spindles in the human zygote

  • Xiaoming Xu
  • Linheng Li
  • Chuilian Zhang
  • Li MengEmail author
Letter to the Editor

Dear Editor-in-Chief:

The article by Reichmann and colleagues recently published in Science [ 1] raises a number of issues regarding the earliest stages of mammalian embryo development. They report the existence of two distinct and spatially separate bipolar spindles in mouse zygotes, which appear to function independently during the first mitotic division. These observations beg the question of whether human zygotes may exhibit a similar spindle assembly and function mechanism. Here, we report a similar situation where a human zygote containing two individual spindles was observed in the course of our ongoing research. As shown in Fig.  1, the zygote in question was fixed in anaphase of the first cell cycle and processed for confocal fluorescence microscopy after labeling the sample with DAPI (for chromatin blue), NuMa (red), and tubulin (for spindle, green following standard immunofluorescent protocols). What is apparent is that the long axis of the two spindles is aligned in parallel...



We thank Alyssa Meng (University of California At Santa Barbara) for editing of the manuscript.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Beijing Perfect Family HospitalBeijingChina
  2. 2.Stowers Institute for Medical ResearchKansas CityUSA
  3. 3.Department of Pathology and Laboratory MedicineUniversity of Kansas CityKansasUSA
  4. 4.Reproductive Medicine CenterHenan Provincial People’s HospitalZhengzhouChina
  5. 5.LA IVF ClinicLos AngelesUSA

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