Research reported in a collection of 14 articles in the April 2006
issue of the journal Pharmacogenomics, has documented, for the first
time, a genetic basis to chronic fatigue syndrome (CFS) - also known
as ME or post-viral fatigue syndrome.
The series of papers, produced by the US Centers for Disease Control (CDC), presents
an analysis of the most detailed and comprehensive clinical study ever carried
out on CFS.
The study itself involved a meticulously thorough investigation of 227 adults,
including non-fatigued 'controls' for comparison, as well as CFS patients. During
two days spent on a hospital ward, the volunteers underwent detailed clinical
evaluations - measurement
of sleep physiology, cognitive function, autonomic nervous system function and
extensive blood and urine tests as well as psychiatric evaluation and assessment
of their medications. Perhaps most importantly, an assay was also carried out
of the activity of 20,000 genes, in the hope of identifying factors that potentially
cause or are related to CFS.
Genetic predisposition
The resulting data included 500 clinical measures and details of the 20,000 measures
of gene expression (the process by which genes regulate cell activity). The data
was independently examined by four specially assembled teams of investigators
that included medical experts, molecular biologists, epidemiologists, physicists,
mathematicians and engineers.
The results showed that people with CFS have specific genes and gene activity
patterns that render their
bodies unable to adapt to the
challenges and stresses encountered throughout life, such as infections, injury,
trauma, and other adverse events. Chronic fatigue patients were, for example,
twice as likely as controls to have high levels of 'allostatic load', which is
a measure of stress hormone secretions, blood pressure and other signs of wear
and tear on the body.
Also of significance is the finding that there are at least five subtypes of
CFS, classified according to criteria that include their genetics and the way
that their symptoms unfold.
A biological basis
The creation of a molecular profile of individuals with CFS has been hailed as
a very important step forward. Knowing that there is a biological basis for CFS
will help researchers identify more effective ways to diagnose the illness (currently
diagnosed on symptoms, in the absence of evidence of particular alterations in
the body or from blood tests) and should assist in producing more effective treatments.
Moreover, no doctor should ever again dismiss ME/CFS as 'all in the mind'.
The US Centers for Disease Control are a division of the US Department of Health
and Human Services, the principal US agency for protecting the health and safety
of the nation. The fact that this study emanates from this particular source
adds credibility to its findings. However, this work does need to be replicated
in a completely independent sample, and many questions remain to be answered.
The CDC is already in the process of collecting more data on CFS from people
in a different part of the US, as part of an even larger study.
Click
here for further details.
Click here for more articles
Back to top |
