The FDA has approved several immunotherapy agents for the treatment of MM, including monoclonal antibodies targeting CD38 (Daratumumab, Isatuximab) [3–5], CS1/SLAMF7 (Elotuzumab) [6], BCMA-directed antibody-drug conjugates (belantamab mafondotin) [7], BCMA-directed autologous CAR-T cells (Abecma, Carvykti) [8, 9], BCMA or GPRC5D-directed bispecific antibodies (Teclistamab, Elranatamab, Talquetamab) [10–12], proteasome inhibitors and immunomodulatory drugs [13, 14]. The gene discussed is GPRC5D; the disease is Miyoshi myopathy.