HGRV100, 02.09.2011: The origin of the XMRV variant of human gammaretroviruses (HGRVs) has not been shown to be the cell line 22Rv1. The assays used were not always adequate, they were not all used to screen everything equally and they did detect XMRV in the early xenografts, so the patient the cells were taken from was infected with the virus.
The two viruses given the name PreXMRV-1 and 2 could not have created XMRV. One has not been shown to exist and they have not been shown to predate XMRV. There was also no attempt made to find PreXMRV-2 in wild mice, where XMRV is more likely to have been created decades ago.
Leaving out the RT-PCR assay from the paper is not in the interests of Science and the magazine should now retract that paper from Vinay Pathak and John Coffin.
Paprotka et al.
Video of Pathak stating they used an RT-PCR assay
There are a couple of spelling mistakes in the video, but there is no time to upload again.
Please skip to 11min 30 in if you only want to see one reason why the paper did not find the origin.