Recent mounting evidence indicates that MM cells suppress osteoblastogenesis through contact-dependent cell–cell interaction [7,34] and the production of osteoblast-inactivating factors including Wnt inhibitors, such as dickkopf-1 [10] and secreted frizzled-related protein 2 [35], and cytokines, such as CCL3 (also known as macrophage inflammatory protein-1 alpha) [11], hepatocyte growth factor, and IL-3/6 [18]. The gene discussed is HGF; the disease is Miyoshi myopathy.