The novel human retrovirus xenotropic murine leukemia virus-related virus (XMRV) is arguably the most controversial virus of this moment. After its original discovery in prostate cancer tissue from North American patients, it was subsequently detected in individuals with chronic fatigue syndrome from the same continent. However, most other research groups, mainly from Europe, reported negative results. The positive results could possibly be attributed to contamination with mouse products in a number of cases, as XMRV is nearly identical in nucleotide sequence to endogenous retroviruses in the mouse genome. But the detection of integrated XMRV proviruses in prostate cancer tissue proves it to be a genuine virus that replicates in human cells, leaving the question: how did XMRV enter the human population? We will discuss two possible routes: either via direct virus transmission from mouse to human, as repeatedly seen for, e.g., Hantaviruses, or via the use of mouse-related products by humans, including vaccines. We hypothesize that mouse cells or human cell lines used for vaccine production could have been contaminated with a replicating variant of the XMRV precursors encoded by the mouse genome.
Keywords: XMRV, mouse, retrovirus, vaccine, transmission
Citation: van der Kuyl AC, Cornelissen M and Berkhout B (2011) Of mice and men: on the origin of XMRV. Front. Microbio. 1:147. doi: 10.3389/fmicb.2010.00147
Received: 20 September 2010;
Accepted: 26 December 2010;
Published online: 17 January 2011.
Edited by:Antti Vaheri, University of Helsinki, Finland
Reviewed by:Jonas Blomberg, Uppsala University and Uppsala Academic Hospital, Sweden
Copyright: © 2011 van der Kuyl, Cornelissen and Berkhout. This is an open-access article subject to an exclusive license agreement between the authors and the Frontiers Research Foundation, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.
*Correspondence: Ben Berkhout, Laboratory of Experimental Medicine, Department of Medical Microbiology, Academic Medical Center, Meibergdreef 15, 1105 AZ Amsterdam, Netherlands. e-mail: firstname.lastname@example.org