Bob, are you going to post the name of even one Virologist (not employed by WPI) that thinks that the WPI genbank DNA samples are not evidence of contamination?
If there is scientific controversy, that's one thing. But if every Virologist (not employed by WPI) says one thing, and none say the other (unless they work for WPI, of course!) then there isn't any controversy at all. There are just a bunch of forum posters who don't like the answer.
Joshua, if you are going to post on the forum, then please be courteous enough to read other people's posts, and to engage with other users in a meaningful way. I've already addressed the points that you've raised in this post, a number of times.
You don't seem to have a grasp of the science, which is perfectly OK, but please don't accuse other forum members of being ignorant, or anti-science, or biased, when it is you who does not have a grasp of the science, and it is you who seems to need or want XMRV to be a contaminant, for whatever reason. I believe that most forum members are open minded about the science, but you clearly are not. If contamination of the WPI's research is ever proved, then I will accept that. If contamination of Alter's research is ever proved, then I will accept that as well. You have concluded that the WPI's research is due to contamination without any conclusive evidence, or even the balance of evidence in your favour. Your conclusions are without foundation.
All I can do is attempt to explain the science to you, and to present you with the evidence, but if you refuse to engage or to try understand the science that is presented to you, then I can't do anything about that, but I would ask you that you stop insulting other forum members.
As I've already said, I'm not aware of any researchers making any conclusions either way about the WPI's
latest genback samples in a peer reviewed analysis.
But as I've also explained, there are a number of reasons why a lack of variety in viral sequences does not prove contamination, and I have provided references to articles in scientific journals which demonstrate this. (5)
I'm personally not aware of any scientists who have said that the WPI's newest sequences prove contamination. Are there any? You are wrong to say that no scientists, except those employed by the WPI, believe that the WPI's results are not due to contamination. I am aware of quite a number of scientists who believe that the WPI's research is not due to contamination... Please see below...
If you are refering to one or two scientists expressing opinions about the WPI's most recently published XMRV sequences then that isn't evidence. There has been no peer reviewed analysis of the WPI's newest sequences.
You insist that the WPI's findings are due to contamination, but you can't provide conclusive evidence for this.
These are the contamination theories that we have to date:
1. False PCR readings (i.e. cross reactivity).
2. Mouse DNA contamination.
3. XMRV is a mouse virus.
4. DNA contamination from a cell line.
5. XMRV is purely a cell line virus (Purely a lab artifact).
6. XMRV is a wild human virus but doesn't exist in CFS patients.
The WPI has been accused of all of these, and so it's difficult to know which one we are up to at the moment.
There seems to be a general scientific consensus that the first 4 have now been disproved, so we are left with theories 5 and 6.
Theory 5:
The latest accusation, from Coffin & colleagues is that XMRV is a real virus, but that it only exists in cell lines, as a laboratory artifact, and it doesn't exist in the wild, and hasn't infected humans. So these scientists subscribe to theory 5.
However, other prominent scientists do not subscribe to theory 5 because they have detected XMRV in human tissue (1) (3) (11)... So the weakness of theory 5, is the
evidence provided by other scientists such as Singh and Switzer, which demonstrates human infection (1).
So that explains one of the weaknesses of theory 5. But alongside this, the two recent Switzer studies demonstrate XMRV genetic variability (1) and also challenge Coffin's recombination theory (8) (9), thus opening up the possibility that XMRV originated in other places, other than the cell line that Coffin investigated. So this evidence demonstrates further weaknesses in Coffin's and his colleagues' conclusions.
Theory 6:
Singh's theory is slightly different to Coffin's because, when she is refering to her prostate cancer study (3), she believes that XMRV exists in the wild, in prostate cancer patients and in the normal healthy population at 4% (or 6%?). But when Singh is talking about her CFS study, where she tested blood instead of prostate tissue, she fails to detect XMRV, and concludes that XMRV doesn't exist in CFS patients or in the normal healthy population. The weakness of Singhs conclusions is that they are conflicting, based on different results using different methodologies. In her CFS study, XMRV exists in 0% of the population, but in her prostate cancer study, XMRV exists in 4% (or 6%?) of the normal population. So, Singh apparently subscribes to theory 6, although in a rather contradictory fashion, as her prostate cancer study suggests that at least 4% (or 6%?) of CFS/ME patients should test positive for XMRV. It seems to me that Singh has demonstrated only that she can detect XMRV in tissue, but not in blood samples. She has no other explanation for the discrepancies (4).
Switzer also believes that XMRV is a real wild human virus (1), but that it doesn't exist in CFS patients, so he also subscribes to theory 6. However, his opinions are also contradictory, because he admits in a recent study (1) that he has inadequate methodologies to detect XMRV in the blood of any individuals, even when he has confirmed them to be XMRV-positive by testing those individuals' prostate cancer tissue.
So the weakness of theory 6 is the fact that the scientists who have published some of the zero/zero XMRV studies, looking at the blood of CFS patients, have demonstrated that they are unable to detect XMRV in the blood of XMRV-positive patients. This gives us a good reason to suspect that it might be the methodologies that are at issue, rather than an absence of XMRV. There might be other reasons for the discrepancies, but we just don't know the exact reasons at the moment, and nor do the scientists.
The other weakness of theory 6 is the consistent results from the WPI, and the strength of all of their various findings. Then there are the related MLV sequences that Alter and Lo detected. These findings suggest that further research into human infection from MLV-related viruses is worth continuing with.
In terms of the specific allegation that the WPIs results are purely due to contamination, this has been argued over endlessly, so I will just repeat the following... As I have explained earlier, a lack of sequence variability is not proof of contamination for the following reasons:
1. XMRV Mutation behaviour could be similar to HTLV. (6)
2. There could be alternative routes of XMRV transmission in humans such as in vaccines. (5)
3. The WPI have many more XMRV isolates that they have been unable to sequence and publish due to a lack of funding. As our knowledge about XMRV, and the evidence relating to XMRV, continues to grow, then a higher variation in genetic sequences might become evident.
4. A variety of MLV-related sequences such as P-MRVs have been detected by various researchers including the WPI. (10)
5. The consistent nature of the WPI's results, and the strength of their original Science paper suggest that they haven't detected contamination.
Has Switzer, Lipkin, Lo or Alter come out saying that those DNA samples show that it's real?
So are you saying that XMRV is a contaminant only in the WPIs research, or are you saying that XMRV is not a real or wild human virus? These are two entirely separate issues.
As a direct answer to your question, here are the virologists that spring to mind who believe that XMRV is a real virus... And I'm sure that there are more:
Switzer (1), Alter (7), Russceti, Beiger, Hanson (12), Silverman (2)
Alter strongly believes that the WPI's research is evidence of a real human virus in CFS patients (7) (Quotes given earlier in the thread.)
Switzer has provided his own XMRV sequences to genbank (1) which he concludes is evidence that XMRV is a real, wild, human virus, due to the genetic variability.
References:
(1)
http://www.plosone.org/article/info:doi/10.1371/journal.pone.0019065#abstract0
No Association of Xenotropic Murine Leukemia Virus-Related Viruses with Prostate Cancer
Switzer.
"Sequence analysis of the PCR-positive specimens was highly informative because it confirmed that all three specimens were XMRV-related. Also, the finding of a viral strain in three prostate cancer patients that is distinct from the XMRV seen in previous studies is significant and demonstrates a broader viral diversity. This would be an expected result consistent with virus evolution during spread and persistence."
(2)
http://www.retrovirology.com/content/pdf/1742-4690-8-S1-A241.pdf
Human infection or lab artifact: will the real XMRV please stand up?
Silverman.
(3)
http://www.pnas.org/content/106/38/16351.full
XMRV is present in malignant prostatic epithelium and is associated with prostate cancer, especially high-grade tumors
Singh.
(4)
http://www.cfscentral.com/2011/05/dr-ila-singh-we-are-now-convinced-that.html
Interview with DR. ILA SINGH
"Not entirely sure, but there were different assays (e.g. immunohistochemistry) and different sample types (blood vs prostate tissue)."
(5)
http://www.thelancet.com/journals/laninf/article/PIIS1473-3099(11)70081-0/fulltext
Mouse viruses and human disease
Gkikas Magiorkinis.
(6)
http://forums.phoenixrising.me/show...it-can-explain-XMRV-s-low-degree-of-mutations
HTLV-1's replication: Perhaps it can explain XMRV's low degree of mutations
(7)
http://www.investinme.org/InfoCentre Topics Dr Harvey Alter BPACM.htm
Blood Products Advisory Committee Meeting Transcript
Dr Harvey Alters Closing Remark at the Conference
(8)
http://retroconference.org/AbstractSearch/Default.aspx?Conf=20&Abs=40126
Extensive Genetic Recombination in the XMRV Genome
Switzer.
(9)
http://www.retrovirology.com/content/8/S1/A235
Murine leukemia viruses (MuLV) and Xenotropic MuLV-related viruses exhibit inter-tropic complex recombination patterns
Switzer.
(10)
http://www.pnas.org/content/early/2010/08/16/1006901107.full.pdf+html
Detection of MLV-related virus gene sequences in
blood of patients with chronic fatigue syndrome
and healthy blood donors
Alter & Lo.
(11)
http://www.retrovirology.com/content/8/S1/A222
Prevalence of XMRV in blood donors, HTLV and HIV cohorts
Abbott Diagnostics.
(12)
http://www.retrovirology.com/content/pdf/1742-4690-8-S1-A234.pdf
Detection of MLV-like gag sequences in blood samples from a New York state CFS cohort
Hanson.