MCL is characterized by the t(11;14)(q13;q32) translocation that juxtaposes the cyclin D1 gene (CCND1) to the immunoglobulin (Ig) heavy chain gene (Bertoni et al., 2006), and results in constitutive overexpression of cyclin D1 under the control of an active Ig locus (Baker and Reddy, 2012). The gene discussed is CCND1; the disease is mantle cell lymphoma.