Looks like there are at least two German Studies: Hohn O, Krause H, Barbarotto P, Niederstadt L, Beimforde N, Denner J, Miller K, Kurth R, and Bannert N. Lack of evidence for xenotropic murine leukemia virus-related virus (XMRV) in German prostate cancer patients. Retrovirology 2009. 6:92. Lombardi VC, Ruscetti FW, Das Gupta J, Pfost MA, Hagen KS, Peterson DL, Ruscetti SK, Bagni RK, Petrow-Sadowski C, Gold B, Dean M, Silverman RH, and Mikovits JA. Detection of an Infectious Retrovirus, XMRV, in Blood Cells of Patients with Chronic Fatigue Syndrome. Science 2009. 326: 585-589. Schlaberga R, Choeb DJ, Browna KR, Thakerb HM, and Singh IR. XMRV is present in malignant prostatic epithelium and is associated with prostate cancer, especially high-grade tumors. PNAS 2009. 106: 16351-16356. Urisman A, Molinaro RJ, Fischer N, Plummer SJ, Casey G, Klein EA, Malathi K, Magi-Galluzzi C, Tubbs RR, Ganem D, Silverman RH, DeRisi JL. Identification of a Novel Gammaretrovirus in Prostate Tumors of Patients Homozygous for R462Q RNASEL Variant. PLoS Pathogen 2006 2:211-225. Fischer N, Hellwinkel O, Schulz C, Chun FK, Huland H, Aepfelbacher M, Schlomm T: Prevalence of human gammaretrovirus XMRV in sporadic prostate cancer. J Clin Virol 2008. 43:277-283. D'Arcy F, R. Foley, A. Perry, L. Marignol, M. Lawler, E. Gaffney, R. Watson, J. Fitzpatrick, T. Lynch: No evidence of XMRV in Irish prostate cancer patients with the R462Q mutation. European Urology Supplements 2008. 7:271.