Xenografted peripheral blood cells harboring circulating malignant B cells but lacking detectable plasma cells are able to xenograft human MM to immunodeficient mice, as can leukemic plasma cells and CD34+ progenitor fractions of MM mobilized blood autografts (Pilarski et al. 2002; Pilarski et al. 2000b; Pilarski and Belch, 2002; Reiman, Seeberger, Taylor, Szczepek, Hansen, Mant, Coupland, Belch, and Pilarski, 2001). This evidence concerns the gene CD34 and Miyoshi myopathy.