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Microarray-based Identification of Individual HERV Loci Expression: Application to Biomarker Discovery in Prostate Cancer
Published on: November 2, 2013
Expression pattern analysis of transcribed HERV sequences is complicated by ex vivo recombination
Aline Flockerzi1, Jochen Maydt, Oliver Frank
1Department of Human Genetics, Medical Faculty, University of Saarland, Homburg, Germany. aline.flockerzi@uniklinik-saarland.de
Retrovirology
|June 7, 2007
Summary
Newly discovered human endogenous retrovirus K (HERV-K) sequences, termed HERV-KX, may not represent novel infectious variants. Instead, they likely arise from ex vivo recombination between existing HERV-K(HML-2) proviruses.
Area of Science:
- Genomics
- Molecular Biology
- Evolutionary Biology
Background:
- The human genome contains numerous human endogenous retroviruses (HERVs) from ancestral species.
- The HERV-K(HML-2) family has younger loci, with a recent study suggesting an infectious variant in humans.
Purpose of the Study:
- To investigate expression patterns of specific HML-2 proviruses.
- To determine the origin of HERV-K(HML-2) cDNA sequences lacking proviral homologues.
Main Methods:
- Analysis of HERV-K(HML-2) expression patterns.
- Detailed sequence analysis using the RECCO software.
Main Results:
- Encountered HERV-K(HML-2) cDNA sequences (HERV-KX) without genomic proviral homologues.
- Sequence analysis suggested HERV-KX sequences result from ex vivo recombination between different HML-2 proviral transcripts.
Conclusions:
- Generation of new HERV-K(HML-2) sequences via ex vivo recombination is likely during RT-PCR.
- Newly identified HERV-K(HML-2) variants require cautious interpretation due to recombination and allelic variation.
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