IRF4 and ulnar-mammary syndrome: As shown in the heatmap (Figure 1B), the “B-cell receptor signaling” pathway, the “IRF4 targets in plasma cells vs. mature B lymphocytes” pathway and the “peripheral blood mononuclear cell response to ionizing radiation (IR)” pathway were significantly enriched in M3/BAP1null tumors, suggesting that IRF4 may enhance immunity in BAP1 deficient UMs.