The relative frequency of BCR-ABL kinase domain mutations detected at 31 different positions in clinical specimens from 245 patients in whom mutations were detected (219 with CML and 26 with Ph-positive acute lymphoblastic leukemia). The numbering of amino acids is based on the Abl protein variant B (which includes ABL exon 1b but not exon 1a). The letters inside the circles denote the amino acid encoded by the corresponding mutated nucleotide. At some positions 2 or 3 possible mutant nucleotides encode different amino acids. The percentage of patients in the series with each mutation specified on the y axis is color-coded as shown in the box. Data collated from 20 published papers.^{19-22,24,25,48,52,56-66}