Related Experiment Video
Updated: May 21, 2026
12:04
Mouse Genome Engineering Using Designer Nucleases
Published on: April 2, 2014
The genomic landscape shaped by selection on transposable elements across 18 mouse strains
Christoffer Nellåker1, Thomas M Keane, Binnaz Yalcin
1MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK. christoffer.nellaker@dpag.ox.ac.uk
Genome Biology
|June 19, 2012
Summary
Transposable elements (TEs) are abundant in mammalian genomes, but their impact on gene regulation is complex. Most new TE variants are purged by selection, with few significantly altering gene expression.
Area of Science:
- Genomics
- Molecular Biology
- Evolutionary Biology
Background:
- Transposable elements (TEs) significantly shape mammalian genomes and influence gene regulation.
- Knowledge of TEs in laboratory mice is largely confined to the C57BL/6J reference genome.
- Mechanisms governing TE retention versus purging in mammalian genomes are not well understood.
Purpose of the Study:
- To create a comprehensive catalog of polymorphic TE variants in diverse mouse strains.
- To analyze the evolutionary processes shaping TE distribution over millions of years.
- To investigate the impact of TEs on gene expression and identify causal variants.
Main Methods:
- Whole genome sequencing of 13 laboratory and 4 wild-derived mouse inbred strains.
- Development of a catalog of 103,798 polymorphic TE variants.
- Analysis of TE variant distribution and association with gene expression changes.
Main Results:
- A comprehensive catalog of 103,798 polymorphic TE variants was generated.
- The majority of TE variants originate in the male germline.
- A minority of TE variants cause detectable gene expression changes, but are often purged by selection.
Conclusions:
- Most TE variants influencing gene expression are rapidly eliminated by purifying selection.
- Past TE insertions are frequently deleterious, impacting gene expression or phenotype.
- This study aids in prioritizing TE variants based on their potential functional significance.
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