Hi Friends, here is the long awaited paper!
Lombardi, V.C. et al. 2009. Detection of an
infectious retrovirus, XMRV, in blood cells of
patients with chronic fatigue syndrome. Science,
online October 8. - doi:10.1126/science.1179052
~jan van roijen: see below
Retrovirus might be culprit in chronic fatigue syndrome
People with the condition are much more
likely than others to harbor a little-known
By Nathan Seppa
The long, fruitless search for the cause of chronic
fatigue syndrome has taken a curious turn. Scientists
report online October 8 in Science that an obscure
retrovirus shows up in two-thirds of people
diagnosed with the condition. The researchers also
show the retrovirus can infect human immune cells.
These findings don't establish that the pathogen,
called gammaretrovirus XMRV, causes chronic
fatigue, cautions study coauthor Robert Silverman, a
molecular biologist at the Lerner Research Institute
of the Cleveland Clinic.
"Nevertheless, it's exciting because it is a viable
candidate for a cause."
Roughly 1 to 4 million people in the United States
have chronic fatigue syndrome, according to the
Centers for Disease Control and Prevention.
The condition shows up as mental and physical
exhaustion, memory lapses, muscle pain, insomnia,
digestive distress and other health problems.
Doctors often diagnose chronic fatigue only after
ruling out everything else. Its cause is unknown.
In the new study, the researchers tested blood from
101 people with chronic fatigue syndrome and found
that 68 were infected with XMRV. When the
scientists analyzed blood from 218 healthy people as
a control group, only eight had the virus - 4 percent.
The study participants lived in various parts of the
"This is a very striking association - two-thirds of
the patients," says John Coffin, a virologist at Tufts
University in Boston who wasn't involved in the
study. A 4 percent infection rate in the healthy
controls is also substantial, he notes, because it
suggests that 10 million people in the United States
are harboring this hidden infection.
If the retrovirus indeed is found to cause chronic
fatigue, the infected 4 percent in the control group
might represent people who have been infected for a
short time and haven't developed symptoms, or who
have kept the virus in check, says study coauthor
Judy Mikovits, a cell biologist at Whittemore
Peterson Institute in Reno and at the University of
Based on its genetic makeup, XMRV arose from a
mouse retrovirus that somehow jumped to humans.
Mikovits asserts that the retroviral infection might
result in an immune deficiency that leads to chronic
Retroviruses are known to attack the immune
system, with HIV being the best-known example. In
this study, researchers showed that XMRV infected
immune cells in the blood.
"This may end the controversy as to whether there is
an underlying infection in some cases of chronic
fatigue syndrome, but is unlikely to explain all
cases," says internist Dedra Buchwald of the
University of Washington in Seattle.
Retroviruses can awaken latent viruses already in
cells. It is possible that chronic fatigue symptoms
are caused not by XMRV but by other viruses that it
activates, she says.
Meanwhile, retroviruses harbor pro-growth genes,
and some cause the blood cancer leukemia in
animals and people.
XMRV - or xenotropic murine-leukemia-virus-related
virus - itself shows up in some men with prostate
cancer, particularly those with aggressive
malignancies, another research team reported last
month in the Proceedings of the National Academy of
Gammaretroviruses, a subset of retroviruses, also
cause disease in gibbons, cats and koalas, Silverman
says. "XMRV is the first member of this genus of
retrovirus to be found in humans," he notes.
In the new study, the researchers also found hints
that the retrovirus is transmitted by blood, as are
some other viruses, including HIV.
But it's probably not spreading very fast, because
people with chronic fatigue "are too sick to do
anything," Mikovits says.
Further research is under way to fine-tune testing for
the retrovirus, and more blood analyses are planned
that will clarify its occurrence rate in the general
Mikovits and her colleagues are investigating
already-approved antiretroviral drugs to see if these
will benefit people who have chronic fatigue.