This was first described in multiple myeloma (MM), where ∼20% of cases overexpress MMSET due to the translocation t(4;14) [16], which places the MMSET and FGFR3 loci under regulation of strong immunoglobulin enhancers, leading to abnormally high levels of these factors [17]. The gene discussed is NSD2; the disease is plasma cell myeloma.