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Aneuploidy and gene expression: is there dosage compensation?
Shihoko Kojima1, Daniela Cimini1
1Department of Biological Sciences & Fralin Life Sciences Institute, Virginia Tech, Blacksburg, VA 24061, USA.
Epigenomics
|November 23, 2019
Summary
Aneuploidy, an abnormal chromosome number, causes miscarriage, birth defects, and cancer. Extra chromosomes alter gene expression, but dosage compensation mechanisms may exist, alongside epigenetic changes.
Area of Science:
- Genetics
- Molecular Biology
- Cancer Biology
Background:
- Aneuploidy (abnormal chromosome number) is a primary driver of human miscarriage and congenital defects.
- Aneuploidy is a common feature in various human cancers.
- Gene product imbalance from extra chromosomes is believed to cause detrimental phenotypes.
Purpose of the Study:
- To review current understanding of how extra chromosomes affect gene expression.
- To explore evidence for and against gene dosage compensation mechanisms in aneuploid cells.
- To summarize epigenetic alterations in aneuploid cells and identify future research directions.
Main Methods:
- Literature review of studies investigating gene expression in aneuploid cells.
- Analysis of research on gene dosage and transcript levels.
- Examination of studies on epigenetic modifications in aneuploidy.
Main Results:
- Studies show a direct correlation between gene dosage and transcript levels in aneuploid cells.
- Some research indicates a less stringent correlation, suggesting potential dosage compensation.
- Epigenetic changes are observed in aneuploid cells, though their full impact is under investigation.
Conclusions:
- Aneuploidy significantly impacts gene expression, with varying degrees of correlation to gene dosage.
- Dosage compensation mechanisms may mitigate the effects of extra chromosomes.
- Further research is needed to elucidate epigenetic alterations and their functional consequences in aneuploidy.
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