Gene probe sets discriminating cross-resistance (CR) and VCR-ASP discordant resistance (VA) in B-lineage ALL patients were grouped according to 12 major functional categories. Each diagram shows the percentage of probe sets with GO annotation in the list of discriminating genes versus all genes represented on the U133A GeneChip. The entire genome, as represented by the 12,304 probe sets annotated in the GO database, has a total of 20,113 annotations. 51 probe sets discriminating CR (32 probe sets with GO annotation) and 200 probe sets discriminating VCR and ASP discordant resistance (142 probe sets with GO annotation) were used. Fisher's exact test (*P<0.05) was used to estimate significance of over- or under-representation of the discriminating probe sets.