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Microarray-based Identification of Individual HERV Loci Expression: Application to Biomarker Discovery in Prostate Cancer
Published on: November 2, 2013
Human endogenous retroviruses: from infectious elements to human genes.
1Unité des Rétrovirus Endogènes et Eléments Rétroïdes des Eukaryotes Supérieurs, UMR 8122 CNRS, Institut Gustave Roussy, Villejuif, France.
Cytogenetic and Genome Research
|August 12, 2005
Summary
Mammalian genomes host numerous endogenous retroviruses (ERVs), remnants of ancient infections. Some human ERVs (HERVs) retain functions and may be integrated into host biology.
Area of Science:
- Genomics
- Molecular Biology
- Virology
Background:
- Mammalian genomes, including the human genome (42%), are heavily populated by retroelements, mobile genetic sequences.
- A substantial fraction of these are endogenous retroviruses (ERVs), derived from ancient germline infections by active retroviruses.
Purpose of the Study:
- To provide a comprehensive survey of human ERVs (HERVs) following the completion of the human genome sequence.
- To analyze the phylogenetic and functional similarities between HERVs and modern retroviruses.
- To investigate the potential roles and implications of HERVs in human biology and disease.
Main Methods:
- Phylogenetic analyses of conserved domains (e.g., reverse transcriptase in pol, transmembrane subunit in env).
- Genomewide screening for human retroviral genes with coding capacity.
- Analysis of HERV gene transcription in healthy human tissues.
Main Results:
- HERVs can be classified into approximately 80 distinct families based on sequence homology.
- Phylogenetic analyses reveal shared ancestry and history between HERVs and present-day retroviruses.
- Despite mutations, some HERVs exhibit functional similarities to retroviruses, including viral-like particle formation and envelope protein activity.
- A genomewide screen identified 16 fully coding HERV envelope genes, with three highly transcribed in healthy tissues like the placenta.
Conclusions:
- HERVs are not merely genomic fossils but contain potentially active genes that have been co-opted by the host.
- These subverted genes may play physiological roles and should be considered bona fide human genes.
- Understanding HERVs is crucial for insights into genome evolution, host-pathogen interactions, and potential pathological effects.
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