MYOM2 and Miyoshi myopathy: Multiple myeloma (MM) is a B‐cell malignancy characterized by clonal expansion of plasma cells in the bone marrow and present with typical clinical manifestations, including hypercalcemia, renal failure, anemia, and bone lesions.1 Monoclonal gammopathy of undetermined significance (MGUS), a pre‐malignant condition, which progresses to MM at rate of 1% per year.2 Early treatment can decrease M‐protein level in MUGS patients.3 Although serum M‐protein and bone marrow plasma cells are used for diagnosis and discrimination of MM and MGUS, these existing markers are limited.