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An unbiased metagenomic search for infectious agents using monozygotic twins discordant for chronic fatigue

Patrick F Sullivan12*, Tobias Allander3, Fredrik Lysholm45, Shan Goh3, Bengt Persson45, Andreas Jacks2, Birgitta Evengård6, Nancy L Pedersen2 and Björn Andersson4*

Author affiliations

1 Department of Genetics, University of North Carolina at Chapel Hill, NC, USA

2 Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden

3 Laboratory for Clinical Microbiology, Department of Microbiology, Tumor and Cell Biology, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden

4 Department of Cell and Molecular Biology, Science for Life Laboratory, Karolinska Institutet, Stockholm, Sweden

5 IFM Bioinformatics, Linköping University Linköping, Sweden

6 Department of Clinical Microbiology, University of Umeå, Umeå, Sweden

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Citation and License

BMC Microbiology 2011, 11:2  doi:10.1186/1471-2180-11-2

Published: 2 January 2011



Chronic fatigue syndrome is an idiopathic syndrome widely suspected of having an infectious or immune etiology. We applied an unbiased metagenomic approach to try to identify known or novel infectious agents in the serum of 45 cases with chronic fatigue syndrome or idiopathic chronic fatigue. Controls were the unaffected monozygotic co-twins of cases, and serum samples were obtained at the same place and time.


No novel DNA or RNA viral signatures were confidently identified. Four affected twins and no unaffected twins evidenced viremia with GB virus C (8.9% vs. 0%, p = 0.019), and one affected twin had previously undetected hepatitis C viremia. An excess of GB virus C viremia in cases with chronic fatigue requires confirmation.


Current, impairing chronic fatigue was not robustly associated with viremia detectable in serum.