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Updated: May 9, 2026
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Using Mouse Oocytes to Assess Human Gene Function During Meiosis I
Published on: April 10, 2018
A human CEP120 gene variant impairs meiotic spindle building causing aneuploidy†
Marlena Duke1,2,3, Cecilia S Blengini1,2, Sophia Maddocks1,2
1Department of Genetics, Rutgers, The State University of New Jersey, Piscataway, NJ, USA.
Biology of Reproduction
|May 7, 2026
Summary
A genetic variant in the CEP120 gene reduces fertility and increases egg aneuploidy by impairing microtubule nucleation. This finding highlights CEP120 variants as a risk factor for aneuploidy and informs genetic counseling for fertility treatments.
Area of Science:
- Reproductive Biology
- Genetics
- Cell Biology
Background:
- Infertility and pregnancy loss are often caused by aneuploidy, an abnormal chromosome number.
- Aneuploidy typically results from chromosome missegregation during oocyte (egg) formation.
- The CEP120 gene, involved in spindle building, is a key focus for understanding genetic causes of aneuploidy.
Purpose of the Study:
- To investigate the functional significance of a previously identified CEP120 genetic variant associated with embryonic aneuploidy.
- To assess the impact of this variant on female fertility, egg aneuploidy, and oocyte microtubule organization.
Main Methods:
- Generated a knock-in mouse model with the CEP120 genetic variant.
- Assessed fertility, egg aneuploidy rates, and microtubule nucleation efficiency in variant mice.
- Manipulated mouse oocyte spindle assembly to mimic human oocytes for comparative analysis.
Main Results:
- Female mice with the CEP120 variant exhibited reduced fertility and increased egg aneuploidy.
- Oocytes from variant mice showed impaired microtubule nucleation efficiency.
- Mimicking human oocyte spindle assembly in variant mice further increased aneuploidy levels.
Conclusions:
- The CEP120 genetic variant functionally impairs oocyte quality and contributes to aneuploidy.
- Common CEP120 variants may predispose individuals to aneuploidy, impacting fertility.
- Patients with CEP120 variants may need specialized genetic counseling regarding egg cryopreservation.
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