Mouse retroviruses and chronic fatigue syndrome: Does X (or P) mark the spot?

摘要

Five years ago, a retrovirus resembling a murine leukemia virus (MLV) was found in patients with prostate cancer (1), and last year, a similar gammaretrovirus was identified in patients with chronic fatigue syndrome (CFS) (2). The agent was named xeno-tropic MLV-related virus (XMRV), because its env gene was nearly identical to that of xenotropic MLV, an infectious endogenous MLV that preferentially infects cells from foreign species, including humans (Fig. 1A) (3).