Southern blot analysis of genomic DNA. Autoradiography after hybridization with ³²P-labeled DNA probes for detection of bcl-2 gene rearrangements in major (lanes 23, 52, 11) and minor breakpoint region (lane 298). Lanes 23, 52: follicle center lymphomas; lane 11: diffuse large B-cell lymphoma; lane 298: mantle cell lymphoma. Dashes indicate the germline bands and arrowheads the rearranged fragments. The molecular-weight marker is indicated on the left.