Detection of murine leukemia virus or mouse DNA in commercial RT-PCR reagents and human DNAs.
The xenotropic murine leukemia virus (MLV)-related viruses (XMRV) have been reported in persons with prostate cancer, chronic fatigue syndrome, and less frequently in blood donors. Polytropic MLVs have also been described in persons with CFS and blood donors. However, many studies have failed to confirm these findings, raising the possibility of contamination as a source of the positive results. One PCR reagent, Platinum Taq polymerase (pol) has been reported to contain mouse DNA that produces false-positive MLV PCR results. We report here the finding of a large number of PCR reagents that have low levels of MLV sequences. We found that recombinant reverse-transcriptase (RT) enzymes from six companies derived from either MLV or avian myeloblastosis virus contained MLV pol DNA sequences but not gag or mouse DNA sequences. Sequence and phylogenetic analysis showed high relatedness to Moloney MLV, suggesting residual contamination with an RT-containing plasmid. In addition, we identified contamination with mouse DNA and a variety of MLV sequences in commercially available human DNAs from leukocytes, brain tissues, and cell lines. These results identify new sources of MLV contamination and highlight the importance of careful pre-screening of commercial specimens and diagnostic reagents to avoid false-positive MLV PCR results.
Laboratory Branch, Division of HIV/AIDS Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
HaoQiang
H
Zheng
Hongwei
H
Jia
Anupama
A
Shankar
Walid
W
Heneine
William M
WM
Switzer
D000818:Animals; D045744:Cell Line, Tumor; D059018:DNA Contamination; D004279:DNA, Viral / Q000032:analysis*; D005189:False Positive Reactions; D006801:Humans; D007202:Indicators and Reagents; D009052:Leukemia Virus, Murine / Q000201:enzymology / Q000235:genetics*; D051379:Mice; D010957:Plasmids / Q000235:genetics; D012194:RNA-Directed DNA Polymerase; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*
D004279:DNA, Viral; D007202:Indicators and Reagents; D012194:RNA-Directed DNA Polymerase