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Updated: Jul 3, 2026
10:08
Determining the Role of Maternally-Expressed Genes in Early Development with Maternal Crispants
Published on: December 21, 2021
Maternally and paternally silenced imprinted genes differ in their intron content
Marie E Fahey1, Walter Mills, Desmond G Higgins
1Department of Biochemistry, Biosciences Institute, University College Cork, College Road, Cork, Ireland.
Comparative and Functional Genomics
|July 17, 2008
Summary
Maternally silenced imprinted genes show reduced intron content in humans and mice. Intronless genes are exclusively found in this maternally silenced group, suggesting distinct evolutionary pressures on imprinted gene regulation.
Area of Science:
- Genomics
- Developmental Biology
- Epigenetics
Background:
- Imprinted genes silence one parental allele during embryonic development.
- Previous studies suggested reduced intron content in imprinted genes, but lacked statistical power.
- The source of this intron content difference remained unclear.
Purpose of the Study:
- To re-investigate intron content in imprinted genes using larger datasets.
- To analyze differences between maternally and paternally silenced imprinted genes.
- To compare imprinted gene intron content across human and mouse models.
Main Methods:
- Utilized large datasets of human and mouse imprinted and non-imprinted genes.
- Separately analyzed maternally and paternally silenced imprinted gene datasets.
- Quantified and compared intron content and intronless gene distribution.
Main Results:
- Maternally silenced imprinted genes exhibit reduced intron content in both human and mouse.
- Intronless genes are exclusively found within the maternally silenced imprinted gene set.
- Human paternally silenced genes showed no difference from controls; mouse paternally silenced genes had increased intron content.
- Significant differences in intron-related parameters were observed between mouse maternally and paternally silenced genes.
Conclusions:
- Maternal imprinting is associated with reduced intron content and a bias towards intronless genes.
- Paternal imprinting shows species-specific differences in intron content.
- These findings suggest distinct evolutionary mechanisms shaping maternally and paternally expressed imprinted genes.
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