Rabbit Anti-Human IRF4 monoclonal antibody for IHC-P, WB. The MUM1 (Multiple Myeloma Oncogene 1) gene was originally identified because of its involvement in the t(6;14) translocation observed in multiple myeloma, which causes juxtaposition of the MUM1 gene to the Ig heavy-chain locus. MUM1 is expressed in a wide spectrum of lymphoid neoplasms but not in myeloid and extra-hematopoitic tumors. MUM1 is a valuable marker for understanding and characterizing histogenesis of B-cell lymphomas. It is an excellent marker for Reed-Sternberg cells of classic Hodgkin and quote;s disease.