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Updated: Jun 24, 2026
08:08
Application of Mouse Parthenogenetic Haploid Embryonic Stem Cells as a Substitute of Sperm
Published on: November 19, 2020
Asynchronous replication and autosome-pair non-equivalence in human embryonic stem cells
Devkanya Dutta1, Alexander W Ensminger, Jacob P Zucker
1Center For Human Genetic Research and Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Simches Research Center, Boston, MA, USA.
Plos One
|March 28, 2009
Summary
Human embryonic stem cells show allele-specific replication for X-linked and autosomal genes. This coordinated replication across chromosome pairs suggests early epigenetic mechanisms distinguishing parental alleles.
Area of Science:
- Genetics
- Epigenetics
- Developmental Biology
Background:
- Mammalian genes can display random monoallelic expression and asynchronous replication.
- This phenomenon is observed in X-inactivation and autosomal genes like odorant receptors and immunoglobulins.
- In differentiated cells, this replication is chromosome-wide, suggesting chromosome-pair non-equivalence.
Purpose of the Study:
- To investigate the replication patterns of randomly asynchronously replicating genes in undifferentiated human embryonic stem cells.
- To determine if allele-specific replication and chromosome-pair non-equivalence exist in human embryonic stem cells.
- To explore the emergence of epigenetic mechanisms distinguishing parental alleles in early development.
Main Methods:
- Utilized a fluorescence in situ hybridization (FISH)-based assay.
- Analyzed the replication patterns of both X-linked and autosomal genes.
- Examined replication coordination at the whole chromosome level, including across the centromere.
Main Results:
- Confirmed allele-specific replication of X-linked genes in human embryonic stem cells.
- Demonstrated random monoallelic autosomal gene replication in these cells.
- Showed replication coordination at the whole chromosome level, crossing the centromere, indicating autosome-pair non-equivalence.
Conclusions:
- Allele-specific replication and autosome-pair non-equivalence are present in human embryonic stem cells.
- Epigenetic mechanisms for distinguishing parental alleles begin to emerge in the inner cell mass.
- These findings provide insights into early epigenetic programming during human development.
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