A20 deletion in MCLs and DLBCLs. (A) The heat map represents log2 ratios of bacterial artificial chromosome (BAC)/P-1 phage-derived chromosome (PAC) clones, which are shown in order from chromosome band 6q centromere (6qcen) to 6q telomere (6qter). The genomic profiles of the chromosome band 6q are depicted in 29 cases of MCL and 46 cases of DLBCL. DLBCL cases are divided into 18 cases of GCB and 28 cases of ABC subtypes as defined.¹²  Relative copy number log2 ratio is displayed according to the color scale. represents the location of A20. (B) Dual-color FISH analysis of DLBCL and MCL cases was performed with a combination of the BAC RP11-356I2 (A20 gene probe) green probe and RP11-277K14 (6q centromere probe) red probe to confirm array CGH results. Representative results of FISH analysis are shown. Two red signals (arrowheads) and one green signal (white arrow) are seen in one cell, indicating heterozygous deletion of the A20 gene, and 2 red signals but no green signal are seen in another cell, indicating homozygous deletion of the A20 gene.