New xmrv study - researcher responds to PCR ENV question

[judderwocky]

Retroviruses have been linked to a variety of diseases such as neoplastic and immunodeficiency disorders and neurologic and respiratory diseases. Recently, a novel infectious human retrovirus, the xenotropic murine leukemia virus-related virus (XMRV), has been identified in cohorts of patients with either a familial type of prostate cancer or chronic fatigue syndrome.

The apparent unrelatedness of these diseases raised the question of the potential involvement of XMRV in other diseases.Here, we investigated the presence of XMRV in a selection of pediatric idiopathic infectious diseases with symptoms that are suggestive of a retroviral infection, as well as in children with respiratory diseases and adult patients with spondyloarthritis (SpA). Using a XMRV env-nested PCR, we screened 72 DNA samples obtained from 62 children hospitalized in the Montpellier university hospital (France) for hematological, neurological or inflammatory pathologies, 80 DNA samples from nasopharyngeal aspirates from children with respiratory diseases and 19 DNA samples from SpA.None of the samples tested was positive for XMRV or MLV-like env sequences, indicating that XMRV is not involved in these pathologies.

Author: Eric JeziorskiVincent FoulongneCatherine LudwigDjamel LouhaemGilles ChiocchiaMichel SegondyMichel RodiereMarc SitbonValerie Courgnaud
Credits/Source: Retrovirology 2010, 7:63

I don't know how stupid you can get testing the same bad sequence over and over again.

Ruscetti et all have said in several lectures that the ENV section mutates in humans too much to be of any use. If you focus on the ENV protein you're probably only going to be able to find a fraction, if any , of the cases.

Aside from the fact that Ruscetti used patient derived XMRV, they also looked at the GAG sequence which is more stable than the ENV.

They should stop stating this emphatically. After the FDA paper comes out Retrovirology is going to have egg all over its face for not figuring this out.

http://7thspace.com/headlines/35276...iatric_idiopathic_diseases_in_france.html#cst

 

[CBS]

We are clearly compiling an overwhelming amount of evidence with regards to what doesn't work.

 

[judderwocky]

We are clearly compiling an overwhelming amount of evidence with regards to what doesn't work.

LOL ... I know right?

I'm not that worried though... PNAS has more clout than Retrovirology....

 

[V99]

Thanks judderwocky

Do you have the link, please?

 

[judderwocky]

Thanks judderwocky

Do you have the link, please?

added it

http://7thspace.com/headlines/35276...iatric_idiopathic_diseases_in_france.html#cst

 

[V99]

Thank you Judderwocky

 

[Stone]

Has anyone written them (the publishers) and explained that testing this way simply does not work on this retrovirus and that perhaps they might want to let their reviewers in on that?

 

[Hope123]

I haven't read this yet but by the looks of it, it's interesting (tragi-comic?) that they decided to look for XMRV not in kids with CFS but all types of other kids instead. (Don't study the people purported with the disease -- taking a page from the CDC.) At least, this might rule out that XMRV is not as ubiquitous as people believe it to be (aside from issues of technique) --- e.g. being immunosuppressed as might happen with other chronic diseases doesn't mean you have XMRV.

 

[ixchelkali]

It's the journal Retrovirology again, home of the CDC's CFS studies. Your best source for bad XMRV studies. WHO are this jounal's peer reviewers, anyway? Care to guess?

http://www.retrovirology.com/content/7/1/63

 

[SOC]

It's the journal Retrovirology again, home of the CDC's CFS studies. Your best source for bad XMRV studies. WHO are this jounal's peer reviewers, anyway? Care to guess?

http://www.retrovirology.com/content/7/1/63

I was just asking that question on another thread about this paper.

I really have to wonder what Retrovirology is getting out of publishing bad science. Maybe we need to sic the Bad Science boys on some real bad science.

Edit: Or is this the 5th bad science paper about XMRV in Retrovirology?

 

[ixchelkali]

At least, this might rule out that XMRV is not as ubiquitous as people believe it to be (aside from issues of technique) --- e.g. being immunosuppressed as might happen with other chronic diseases doesn't mean you have XMRV.

That's the shame of it: it could be giving us useful information if they only had used a technique shown to work. Now we don't know if XMRV is absent from this population or if they simply didn't find it because of faulty technique. It's a tragic waste of research dollars and time, and it only serves to further obfuscate the issue. They could be right about this group of people, and maybe their technique even worked, but because they didn't use a verified methodology, we don't know. It's so darned frustrating!

With every research team running off on its own, using its own techniques, there's no validation. What, do they expect to have replication studies performed on every study? It's more like a flock of turkeys than research scientists. Does NO ONE understand the basics of methodical scientific technique anymore? Sheesh, it's like some kind of psuedo-scientific wild west. Enough, already!

Okay, ahem, pardon me, rant over. Sometimes my frustration runneth over.

 

[SOC]

It's more like a flock of turkeys than research scientists. Does NO ONE understand the basics of methodical scientific technique anymore? Sheesh, it's like some kind of psuedo-scientific wild west.

ROFLMAO! :tear: :tear:

Couldn't agree more!

 

[judderwocky]

I just contacted one of the researchers on this project and he has given me some very interesting information ! It seems that retrovirology is addressing some of these issues, but I am not sure what effect it will actually have on this study..... I know that some changes have already been made. I got permission to repost this and I definitely think it changes my perception of the state of research going on in this paper... it seems they are aware of these limitations and have actually tried the Gag sequence as well now.


------------------------------------------------------------------------------------------------------------------------------------------------------
Feel free to proceed as you want. But just remind that all of current XMRV data result from preliminary researchs that are a long way from any conclusive interpretations.
Vincent Foulongne
Dr Vincent Foulongne
Laboratoire de Virologie
CHU de Montpellier St Eloi
80, Av A. Fliche 34295 Montpellier
Tel: 33 (0) 467 337 127 (147)
Fax: 33 (0) 467 337 793



Date : 08/03/2010 01:24PM
Objet : Re: RE:Questions

Vincent,

Thank you so much for your informative response! If it is at all
possible to share your words with a patient group I am a part of, I
would definitely appreciate the permission to post them. I definitely
think it would be helpful to them. If you would rather wait until the
information appears elsewhere in print or would simply rather me keep it
private, I definitely respect and understand that as well (or if you
would rather me wait for Dr. Sitbon or Dr. Courgnaud to respond). Again,
thanks for taking the time to share, it is most appreciated.

Many Thanks



On Tue, 2010-08-03 at 10:10 +0200, v-foulongne@chu-montpellier.fr wrote:
> Dear
>
> Your question overlaps one that was raised by a reviewer of our paper
> and answer is now stated in the text. We definitively cannot rule out
> that we may have missed XMRV variant sequences, however this is
> unlikely since current XRMV env sequences available are all
> highly similar (that furthermore raises question relative to the
> recent or not emergence of XMRV in humans....) and we have also tested
> our samples for gag sequences with the same negative results. Our
> hypothesis is that difference in XMRV worldwide distribution is
> related to a particular epidemiological pattern as observed for other
> retroviruses and we agree that discrepancies in European findings
> suggest further investigations.
>
> I forward your question to both Dr Marc Sitbon and Dr Valrie
> Courgnaud for more accurate answers.
>
> Best regards
>
> Vincent Foulongne
>
>
>
> Dr Vincent Foulongne
> Laboratoire de Virologie
> CHU de Montpellier St Eloi
> 80, Av A. Fliche 34295 Montpellier
> Tel: 33 (0) 467 337 127 (147)
> Fax: 33 (0) 467 337 793
>
>

> Date : 08/02/2010 09:22PM
> Objet : Questions
>
> Doctor,
>
> I was wondering if you explain how you were able to overcome
> the hurdles
> to ENV mutations. Its my understanding that the XMRV ENV
> sequence
> mutates and that other researchers have been unable to
> accurately find
> the virus unless they used GAG. How was your lab able to
> overcome this?
> I am very curious and interested!
>
> Thanks for your time!

>
>
>
>
> P Afin de contribuer au respect de l'environnement, merci de
> n'imprimer ce mail qu'en cas de ncessit.
>
>

 

[judderwocky]

sorry to rename the thread, but i felt it was important for the title to reflect more positively on this team.

 

[vdt33]

Good job, judderwocky, and handled very deftly as well.

 

[xrayspex]

hey so judderwocky, how did this letter exchange change your view of xmrv research and also of this team?