Malignancy classification of BM plasma cells in the same dataset (Extended Data Fig. 4c), based on detected copy number aberrations using inferCNV17, showed that upregulation of FCRLB and QPCT expression in plasma cells from MM patients was driven by malignant plasma cells (Extended Data Fig. 6 and Supplementary Table 13). Here, FCRLB is linked to Miyoshi myopathy.