Homozygous deletions and inactivating mutations of the Traf3 gene have been identified in NHL, including splenic marginal zone lymphoma (MZL), B cell chronic lymphocytic leukemia (B-CLL) and mantle cell lymphoma (MCL), as well as multiple myeloma (MM) and Waldenström’s macroglobulinemia (WM) [6-9]. The gene discussed is TRAF3; the disease is mantle cell lymphoma.