Interactions between MM cells and the bone marrow microenvironment (BMM) activate a multitude of proliferative and anti-apoptotic signaling pathways, including the Ras–Raf–MAPK kinase (MEK)–extracellular signal-regulated kinase (ERK) pathway and the Janus kinase/signal transducer and activator of transcription (JAK-STAT) pathway45. The gene discussed is MAP2K7; the disease is Miyoshi myopathy.