The National Institutes of Health (NIH) formed The Blood XMRV Scientific Research Working Group including the Food and Drug Administration, the Centers for Disease Control and Prevention, blood banks, academic institutions and a patient advocacy organization. The working group is investigating ways to test for the retrovirus XMRV and any possible danger it may present to the blood supply.
Six labs are involved. They are two FDA labs, as well as labs at the National Cancer Institute, the CDC, the Blood Systems Research Institute and the Whittemore-Peterson Institute. These labs have analyzed blood samples containing different amounts of the retrovirus XMRV, in order to determine whether or not the labs' tests are able to detect XMRV in the blood. This was successful.
"Phase four will analyze blood from 300 blood donors, 25 confirmed XMRV-positive patients, and 30 XMRV-negative samples from 10 independent blood donors. This data will finally get researchers a little closer to answering at least one of the key questions in the still-unfolding drama: Is XMRV widespread in the nation’s blood supply?"
http://blogs.wsj.com/health/2010/07/26/fda-advisory-committee-to-hear-about-xmrv-working-groups-research