Mantle cell lymphoma (MCL) is a heterogeneous aggressive lymphoid malignancy that accounts for approximately 3–8% of non-Hodgkin's lymphoma (NHL) cases; it is characterized by the nonrandom chromosomal translocation t(11, 14) (q13; 32) and leads to overexpression of cyclin D1 [1]. The gene discussed is CCND1; the disease is mantle cell lymphoma.