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Amplification, Next-generation Sequencing, and Genomic DNA Mapping of Retroviral Integration Sites
Published on: March 22, 2016
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Unfixed endogenous retroviral insertions in the human population
Emanuele Marchi1, Alex Kanapin2, Gkikas Magiorkinis3
1Department of Zoology, University of Oxford, Oxford, United Kingdom.
Journal of Virology
|June 13, 2014
Summary
Human endogenous retroviruses (HERVs), specifically HERV-K(HML2), are linked to diseases. This study discovered new HERV-K(HML2) genetic loci not present in the human reference genome, aiding disease research and potential immunotherapy targets.
Area of Science:
- Genomics and retrovirology research.
- Human endogenous retroviruses (HERVs) and their role in disease.
Background:
- Human endogenous retroviruses (HERVs) constitute about 5% of the human genome.
- HERV-K(HML2) is upregulated in various diseases, including cancers and HIV infection.
- Understanding individual differences in HERV carriage is crucial for disease causality and immunotherapy.
Purpose of the Study:
- To identify novel HERV-K(HML2) loci absent from the human reference genome.
- To investigate the potential role of HERVs in disease etiology.
- To assess the feasibility of using HERVs as immunotherapy targets.
Main Methods:
- Conducted a detailed search for HERV-K(HML2) loci using next-generation sequencing data.
- Analyzed whole-genome sequences from 358 individuals.
- Compared observed loci frequencies with expectations from a neutral population genetic model.
Main Results:
- Identified 17 novel HERV-K(HML2) loci not present in the human reference genome.
- Found significant variation in locus presence, ranging from 2% to over 95% of individuals.
- Each individual, on average, carried six novel HERV-K(HML2) loci.
- Evidence suggests HERV-K(HML2) replication continued until at least 250,000 years ago.
Conclusions:
- The study provides the first comprehensive catalog of HERV-K(HML2) loci absent from the reference genome.
- These findings enhance our understanding of HERV diversity and individual genetic variation.
- The identified loci are critical for future research into HERV-K(HML2)'s role in disease and its potential as an immunotherapy target.
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