DR. ALTER: Since Dr. Lo had to leave early, I felt I had to come up
and do some defense of him and Judy as well. I think, when a group
finds a new agent, they become biased that this agent is real. When
another group doesn't find an agent, they become, I think, even more
biased that the agent is not real. That leads to this kind of
I think our goal should be not to bring the other side down, but to
find the truth. I think the truth will out over the next year, with
studies that are already planned.
At this point I concur that we have no evidence for causality.
That's going to be very difficult to come by, especially when we are
detecting at the limits of detectability and when assay performance
is very critical to get equal results.
But I still want to counter by saying I think the current evidence
for disease association is very strong, even though not universally
confirmed. But it has been confirmed now in at least four studies,
two of which were presented today, that either XMRV or a polytropic
MLV is associated strongly with chronic fatigue syndrome. A point
that I think was misrepresented today: In those labs who do find the
agent, it is very reproducible. Judy has found the same patients to
be positive by culture year after year. We have found a patient to
come back after 15 years and still be positive. So this is not a
single, isolated finding. It's confirmed by sequencing. It's
reproducible over time.
Dr. Hanson has shown today how critical the assays are. When she
tweaked her assay, she went from no findings to findings almost
identical to the Lo lab. The diversity is now being confirmed also
in the original WPI group. XMRV isn't the only agent even in the WPI
Despite the very legitimate concern for contamination -- I think
this is a serious issue -- there have been hundreds of negative
controls in the same laboratory that are always consistently
negative. An extremely sensitive mouse mitochondrial DNA has always
been negative in the Lo laboratory. Lo has done the IPA assay that
Dr. Coffin recommended. That is also negative. There just has been
no evidence for contamination. Although you could say maybe the
negatives could be negative somehow and the positives positive for
contamination reasons, it really is not logical that that would be
I'm not a molecular biologist. I defer to Dr. Stoye, who is
world-renowned in that area. But just as a simple doctor, it seems
to me that you have used single-case anecdotal evidence to knock
down the various possibilities. I just want to make a case to the
committee that you can't -- your conclusion is that anything can
happen in assays, and therefore it probably has happened this time.
I think using that kind of anecdotal probability is not valid to
negate reproducible data from four different laboratories. So at
least keep that in mind.
Lastly, I'm not a chronic fatigue doctor, but I have learned a lot
about chronic fatigue in the last six months and have spoken to a
lot of patients. I'm absolutely convinced that when you define this
disease by proper criteria, this is a very serious and significant
medical disease, and not a psychological disease. It has the
characteristics of a viral disease. It usually starts with a
viral-like illness. If XMRV is not the causative agent -- and it may
well not be -- there is still need by other groups to look for the
next agent which may be the case.
Sorry to take so much time.