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Detection of Retrotransposition Activity of Hot LINE-1s by Long-Distance Inverse PCR
Published on: July 27, 2019
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Recent Non-LTR Retrotransposon Activity Predicts Cancer Prevalence in Mammals.
Vahid Nikoonejad Fard1, Marc Tollis1,2
1School of Informatics, Computing, and Cyber Systems, Northern Arizona University, 1295 S Knoles Dr, Bldg. 90, Flagstaff, AZ 86011, USA.
Biorxiv : the Preprint Server for Biology
|September 15, 2025
Summary
Recent retrotransposon activity, particularly L1 and SINE elements, correlates with cancer prevalence across mammal species. Limited activity of these mobile elements may protect against cancer by preserving genome stability.
Area of Science:
- Genomics
- Evolutionary Biology
- Cancer Research
Background:
- Non-long terminal repeat retrotransposons (nLTRs), including L1 and SINEs, are abundant mobile elements in mammalian genomes.
- These elements play roles in mutagenesis and gene regulation during oncogenesis.
- The relationship between recent nLTR activity and species-specific cancer risk beyond humans is largely unknown.
Purpose of the Study:
- To investigate if recent nLTR activity predicts cancer prevalence across diverse mammal species.
- To analyze the association between different nLTR activity metrics and cancer risk.
- To explore the role of nLTRs in cancer development and potential protective mechanisms.
Main Methods:
- Comparative genomic analysis of de novo repeat annotations from 55 mammal species.
- Quantification of nLTR activity: number of active elements, proximity to genes, and gene insertions.
- Correlation analysis between nLTR activity metrics and cancer prevalence data from zoo pathology records.
Main Results:
- Neoplasia prevalence associated with L1 and combined L1-SINE activity.
- Malignancy linked to L1-SINE activity, suggesting an escalating role.
- Higher cancer gene ortholog (CGO) counts correlated with neoplasia prevalence.
- Fusion cancer gene numbers strongly correlated with active L1 elements.
- Species with low cancer prevalence showed restricted activity of at least one nLTR superfamily.
Conclusions:
- Recent nLTR activity, specifically L1 and SINEs, is a significant predictor of cancer prevalence and malignancy across mammals.
- L1 elements may initiate tumorigenesis, while SINEs amplify effects, driving malignancy.
- Genome stability, maintained by limiting retrotransposition, appears protective against cancer.
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