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Published on: September 7, 2017
Characterizing cytosine methylation of polymorphic transposable element insertions using the human pangenome
Xiaoyu Zhuo1,2, Chad Tomlinson3, Edward A Belter3
1Department of Genetics, Washington University School of Medicine, St. Louis, Missouri 63110, USA.
Genome Research
|May 14, 2026
Summary
Transposable elements (TEs) in human cells are usually highly methylated, with distinct patterns. While most TEs don't alter nearby DNA methylation, some can spread their epigenetic marks into adjacent genomic regions.
Area of Science:
- Epigenetics
- Genomics
- Molecular Biology
Background:
- Cytosine methylation is a key epigenetic regulator of the genome.
- Long-read sequencing offers new ways to study DNA methylation patterns.
Purpose of the Study:
- Investigate methylation patterns of transposable element (TE) insertions in human lymphoblastoid cell lines (LCLs).
- Establish general rules for TE methylation by analyzing their profiles, context-dependent adoption, and impact on flanking regions.
Main Methods:
- Utilized long-read sequencing to analyze methylation patterns in LCLs.
- Validated findings against whole genome bisulfite sequencing (WGBS).
Main Results:
- TE insertions are generally highly methylated with class-specific patterns, unlike non-TE insertions that match their genomic context.
- Most TEs showed minimal impact on flanking regions, but some exceptions demonstrated methylation spread.
- A subset of Alu insertions were hypomethylated, especially within CpG islands.
Conclusions:
- TE methylation patterns are largely confined within the element, but some TEs can influence neighboring genomic methylation.
- Findings in LCLs provide a foundation, but broader analysis across cell types is needed.
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