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Updated: Jun 2, 2026
11:13
Using Mouse Oocytes to Assess Human Gene Function During Meiosis I
Published on: April 10, 2018
Meiotic gene variants contribute to recurrent blastulation failure.
Xueqin Chen1, Lizhi Leng1,2, Wenbin He2,3
1NHC Key Laboratory of Human Stem Cell and Reproductive Engineering, Xiangya School of Basic Medical Sciences & Furong Laboratory, Central South University, Changsha, China.
Human Reproduction Open
|June 1, 2026
Summary
Genetic variants in meiotic genes are a key cause of recurrent implantation failure in good-quality embryos. This finding aids in diagnosing and managing couples with unexplained infertility.
Area of Science:
- Reproductive genetics
- Embryology
- Genomics
Background:
- Embryonic development relies on maternal transcripts until the 8-cell stage, then shifts to embryonic genome activation.
- While maternal-effect gene variants cause early arrest, the genetic causes of failure between the 8-cell stage and blastulation are unknown.
- Recurrent blastulation failure in good-quality cleavage-stage embryos (R-GQBF) significantly impacts implantation success.
Purpose of the Study:
- To investigate the genetic etiology of recurrent blastulation failure in morphologically good-quality cleavage-stage embryos.
- To identify genetic variants contributing to R-GQBF.
- To explore the role of meiotic gene variants in embryo development and aneuploidy.
Main Methods:
- Whole-exome sequencing (WES) was performed on 109 individuals from 97 couples with R-GQBF and compared to 1000 controls.
- Chromosomal constitutions of 103 embryos were analyzed via WES, with copy number variation (CNV) parental origin analysis on 13 aneuploid embryos.
- Single-sperm chromosome analysis and single-cell RNA sequencing were conducted on arrested embryos.
Main Results:
- Twenty-five variants in 10 meiotic genes were found in 20 patients (18.3%), with female carriers predominantly having prophase I variants and male carriers having MEIKIN variants.
- Embryos from R-GQBF couples showed a high prevalence of complex aneuploidy (63.1%), with parental origin traced to meiotic variant carriers.
- Single-cell transcriptomics revealed defective embryonic genome activation, impaired lineage specification, and activated stress pathways in arrested embryos.
Conclusions:
- Biparental meiotic variants are an underrecognized cause of R-GQBF.
- Chromosomal analysis and genetic screening for meiotic variants are recommended for etiological investigation in couples with recurrent complex aneuploidy.
- These findings can aid in diagnosis, counseling, and personalized treatment planning for couples experiencing R-GQBF.
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