Cort
Phoenix Rising Founder
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The only bit of 'insider information' I had was that Shane had bumped into a person in the elevator who told him that he had tested positive. That was a long time ago and it was quite exciting since it appeared that the Singh lab was the first to find XMRV in a CFS patient after the WPI.
It turns out that was a 'false positive' - apparently due either to contaminated reagents or from XMRV 'getting out', I guess of spiked samples (?), or by robotic equipment getting contaminated after extracted XMRV DNA from cultured cells.
This is a rough field.......
It turns out that was a 'false positive' - apparently due either to contaminated reagents or from XMRV 'getting out', I guess of spiked samples (?), or by robotic equipment getting contaminated after extracted XMRV DNA from cultured cells.
This is a rough field.......
XMRV is closely related to many mouse retroviruses, and contamination of blood samples or testing reagents with mouse DNA could result in a false-positive test for XMRV. Singh and her colleagues found that some of the positives obtained in other CFS-XMRV studies could be due to the presence of mouse DNA in a reagent used in testing; other positives could be attributed to carry-over of XMRV from positive controls to other samples.
In her own study, Singh initially obtained false positives for XMRV in blood samples. But she determined those false readings were related to robotic equipment that previously had been used for extraction of DNA from XMRV-infected tissue culture cells. Several months later, this equipment led to new samples getting contaminated. When the robotic equipment was abandoned, no more false positives were detected in either CFS patients or healthy patients. Its easy to see how sample extraction and tissue culture processes might be vulnerable to contamination, Singh said.