XMRV Replication Study
Independent confirmation of the relationship between XMRV and ME/CFS in Sweden
Prof Jonas Blomberg and Prof Carl-Gerhard Gottfries
Sect of Clinical Virology, Uppsala University Hospital, Uppsala, Sweden; Institution for Neuroscience and Physiology at the Sahlgrenska Academy, Gothenburg University, and Gottfries Clinic, Mölndal, Sweden
EMEA member for Ireland,
IMET, and the Scottish charity
MER UK, are providing joint funding for this study. The following is borrowed
from the IMET site.
Background and aims
The discovery of a retroviral link to ME/CFS
was reported in the major journal
on 8th October 2009.
The major finding was that DNA from the XMRV virus
could be detected in the peripheral blood mononuclear cells of over two-thirds
of ME/CFS patients’ samples from the blood bank in the Whittemore Peterson
Tissue Repository , but in less than 4% of healthy control samples.
The researchers also reported that XMRV proteins were being expressed in blood cells
from ME/CFS patients at very high levels compared with controls, and that
patient-derived XMRV was infectious and transmissible.
It is now necessary for other independent laboratories
to replicate these findings in their own local populations of
Since the WPI researchers used samples selected from several
regions in the US where "outbreaks of CFS" had been documented (using patients
CDC-1994 and Canadian
Clinical Criteria 2003), blood samples from patients in other areas or
other countries might throw up very different results.
Will ME/CFS samples from other
regions of the US show similar high rates of positivity? What about European
This replication study aims to establish
whether XMRV nucleic acid can be found in peripheral blood mononuclear cells,
plasma and serum of Swedish patients and controls.
The researchers will
retrospectively test previously stored patients’ samples (20 Fukuda-defined
ME/CFS, 20 fibromyalgia, 20 irritable bowel), and 20 controls.
In addition, they
will prospectively test samples from 120 ME/CFS (defined on the Fukuda 1994 and
the Canadian 2003 criteria, similar to patients in the original 2009 report in
Science) who will also have functional assessments.
The investigators conducting this research
Prof Jonas Blomberg is head of
Group of Clinical Virology at the University of Uppsala, and his research
interests include human endogenous retroviruses; the links between endogenous
retroviral sequences (ERVs) of the human genome and diseases such as multiple
sclerosis and schizophrenia; and the development of real time PCRs for common
Carl-Gerhard Gottfries is Professor Emeritus at the Sahlgrenska University
Hospital, Mölndal, and founder of the
Gottfries Clinic which was
formed in Västra Götaland 1998 for patients with fibromyalgia and ME/CFS, and
which is now situated in Mölndal. The unit has three doctors, nurses and medical
secretaries, and it has also conducted basic clinical research, including trials
of immunomodulatory therapy for FM and CFS.
The results of this important replication study should be available in the
Spring/Summer of 2010.
26 November 2009