The observed sensitisation of MM cells to TRAIL killing is associated with increased expression of DR4 and DR5, and with activation of the mitochondrial proapoptotic signalling with Bid cleavage linking the proximal and distal events, although the precise contribution of the parallel/auxiliary pathways to the overall efficacy of apoptosis execution in MM cells is not known at present. The gene discussed is TNFRSF10A; the disease is Miyoshi myopathy.