For example, 6-color flow cytometry in multiple myeloma can detect down to 0.01% levels of myeloma-transformed plasma cells in the bone marrow, as opposed to M-protein levels in peripheral blood which reach the lower limit of detection of 0.1 g/dL at underlying disease burdens ranging from 0.001 to 1%. The gene discussed is MYOM2; the disease is AL amyloidosis.