(A) Identification of fusion transcripts by RT-PCR. Primers used were MLL-7S and CBP-1A (MLL-CBP), and CBP-2S and MLL-11A (CBP-MLL). (B) Partial sequences at the chimeric junctions from five cDNAs (MLL, longer and shorter fragments of MLL-CBP, CBP-MLL, and CBP). longer, longer fragment of 521 bp from patients 1 and 2; shorter, shorter fragment of 407 bp from patient 1. Vertical lines indicate the exon-exon junctions of each gene. Arrows indicate the fusion points of each cDNA.