Aberrations most characteristic of ABC DLBCL included trisomy 3, deletion of chromosome arm 6q, deletions/duplications of 18q, deletion of INK4a/ARF tumor suppressor locus on chromosome 9, and gain-amplification of a 9-megabite (Mb) region on chromosome 19q. The gene discussed is CDKN2A; the disease is diffuse large B-cell lymphoma.