The 5-year survival rate for MM has almost doubled over the last five decades to 49%2, due to wider use of autologous stem cell transplantation and drug classes such as proteasome inhibitors (bortezomib), CD38 monoclonal antibodies and immunomodulatory drugs (IMiDs, such as lenalidomide)3, however MM remains incurable. Here, CD38 is linked to Miyoshi myopathy.