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Different versions of XMRV?


Senior Member
I know there is confusion over test results and more negatives than perhaps some of us had hoped for but I am wondering if it has to do with "versions" of XMRV? I know the version in prostate cancer is somewhat different than what WPI found in CFS. In addition, I believe WPI found two slightly different versions in CFS. The upcoming Cornell/Columbia study looks particularly interesting as it seems they will look at each individual test and see if there are additional versions....versions isn't the right word....but I think there may be molecular weight differences. If this is the case, perhaps it explains why some of the test results are inconclusive or negative.

And that makes me wonder if this mouse retrovirus has hoped MANY times into the human population (via whatever methods) in different regions of the world and different years/decades. That could help explain the variance in symptoms as well as in test results. Anyone have thoughts on this? ~FernRhizome


Senior Member
Nancy Klimas has suggested that there could be regional or continental differences.

Also, the retrovirus Dr Michael Holmes found in CFS patients in the (early?) 1990's....he's apparantly said it wasn't XMRV....perhaps it was a different XMRV though? And what of De Freitas' retrovirus?


Senior Member
Los Angeles, USA
The different versions are genetic variations. Because they are more similar than different, a good test will show the degree to which genetic material matches. So they should be able to find it despite normal genetic variation. But we don't know yet how good the test is.


It's the test

The problem is with the test. It takes (or took) a average of 18 months to to create a reliable commercial test. The WPI used scientific assays to find the virus in the original samples. It has only been about 6 months that VIP dx and others have been working to create a viable commercial test. Come back and retest in a year if you want to know for sure.


"and this too shall pass"
Vancouver Canada suburbs

http://www.davidsbell.com/PrintLynNewsV6N5.htmSo what does this mean? It means that if someone can't find XMRV in a study, it is either because it is not in the patients they tested, or their lab could not detect it even if it was there. Or the strain might be different, or they used the wrong tubes, or the diagnosis was wrong. And on and on. Again using the "force", I would not be surprised if some of the quickest replication studies fail to confirm XMRV. But as long as people do not jump to conclusions too quickly, science will win out. Truth will win out. Thats all I am looking for

I found this at David Bell's londonille


Alice Band

PWME - ME by Ramsay
Mike Holmes (NZ researcher) said that the virus he found was more like a Viisna virus (than mlv). So there may be more than one type of retrovirus around.