From Current Opinion in Virology, published online 18 July 2012 (full text behind paywall).
Recombinant origin, contamination, and de-discovery of XMRV
Krista Delviks-Frankenberry(1), Oya Cingöz(2), John M Coffin(2), Vinay K Pathak(1),
(1) Viral Mutation Section, NCI, HIV DRP, Frederick National Laboratory for Cancer Research, Frederick, MD, United States
(2) Program in Genetics, Sackler School of Graduate Biomedical Sciences, Tufts University, Boston, MA, United States
Abstract
The discovery and de-discovery of the xenotropic murine leukaemia virus-related virus (XMRV) has been a tumultuous roller-coaster ride for scientists and patients.
The initial associations of XMRV with chronic fatigue syndrome and prostate cancer, while providing much hope and optimism, have now been discredited and/or retracted following overwhelming evidence that (1) numerous patient cohorts from around the world are XMRV-negative, (2) the initial reports of XMRV-positive patients were due to contamination with mouse DNA, XMRV plasmid DNA, or virus from the 22Rv1 cell line and (3) XMRV is a laboratory-derived virus generated in the mid 1990s through recombination during passage of a prostate tumor xenograft in immuno-compromised mice.
While these developments are disappointing to scientists and patients, they provide a valuable road map of potential pitfalls to the would-be microbe hunters.
The authors of this opinion are the same authors who provided nothing but opinion in the paper Paprotka et al. 2011. That study did not provide evidence for XMRV having been born during the creation of the 22Rv1 cells and they have not provided evidence that 22Rv1 cells are infected with XMRV.
Mayer et al. 2012 has shown that some of these opinions were definitely incorrect and were able to find the ancestral viruses in wild mice using high-throughput next generation sequencing.
“Highlights
PreXMRV-2 like sequence diversity described for wild caught and inbred mice using high-throughput sequencing
PreXMRV-2 likely originated in M. m. domesticus
PreXMRV-2 not found among rodents sympatric with M.m. domesticus
High-throughput sequencing approaches better at identifying specific viruses than low throughput methods”
http://www.sciencedirect.com/science/article/pii/S0168170212002237
Contamination has never been detected in any of the positive samples from the following studies, Lo, Lombardi (WPI/NCI) Lee, Schalberg, Arnold, Fisher, Grossberg, Dong, Qui, Furuta, Robinson, Danielson. All these studies detected gamma retroviruses which are not XMRV. None sequenced the XMRV virus from their sequences.