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Updated: May 28, 2026

Using Fluorescence In Situ Hybridization (FISH) to Monitor the State of Arm Cohesion in Prometaphase and Metaphase I Drosophila Oocytes
Published on: December 6, 2017
Why is chromosome segregation error in oocytes increased with maternal aging?
Zhen-Bo Wang1, Heide Schatten, Qing-Yuan Sun
1State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
Abstract:
It is well documented that female fertility is decreased with advanced maternal age due to chromosome abnormality in oocytes. Increased chromosome missegregation is mainly caused by centromeric cohesion reduction. Other factors such as weakened homologous recombination, improper spindle organization, spindle assembly checkpoint (SAC) malfunction, chromatin epigenetic changes, and extra-oocyte factors may also cause chromosome errors.
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