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Updated: Aug 15, 2026

Using Mouse Oocytes to Assess Human Gene Function During Meiosis I
Published on: April 10, 2018
Aneuploidy involving chromosome 1 in failed-fertilized human oocytes is unrelated to maternal age
Jingly Fung Weier1, Heinz-Ulrich G Weier, Aida Nureddin
1Department of Obstetrics, Gynecology, and Reproductive Sciences, School of Medicine, University of California, San Francisco, USA. jlfung@itsa.ucsf.edu
Purpose:
To study whether maternal meiotic errors in failed-fertilized oocytes involving chromosome 1 occur at frequencies similar to those involving other autosomes, and whether their frequency is affected by maternal age.
Methods:
Using fluorescence in situ hybridization (FISH), frequencies of aneusomy and chromatid pre-division involving chromosomes 1, 16, 18, and 21 were determined for 273 failed-fertilized oocytes.
Results:
The aneuploidy rate for chromosome 1 was 15.8%, and was neither age-dependent nor significantly different from that for chromosomes 16, 18 or 21. Only chromosome 16 exhibited an age-dependent increase in aneusomy rates. The frequency of chromatid pre-division was lower for chromosome 1 than for chromosome 18 (11.9% vs. 25.4%; p = 0.01), but not different from that for chromosomes 16 or 21.
Conclusion:
Aneuploidy involving chromosome 1 in failed-fertilized oocytes is unrelated to maternal age and occurs at a frequency similar to that for chromosomes 16, 18, and 21.
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