MM patients on active therapy were further distinguished in two groups (G3 and G4) based on the types of treatment (Table 1): WM patients (n = 20) comprise G1, with 11 patients on active therapy, including BTK inhibitor (BTKi)-based or anti-CD20 rituximab-based regimens) and G2, with 9 patients off-therapy. The gene discussed is IBTK; the disease is Miyoshi myopathy.