Patient 2’s diagnosis was IgM MM with an increased number of clonal CD138+, IgM+, cyclin D1+, MUM1+, CD56−/+, CD79−/+, CD20−, CD19−, κ-light chain–negative plasma cells (30–40%) (Figs. 1e–h, 2b). The gene discussed is CD40LG; the disease is Miyoshi myopathy.