Frequency of specific karyotypes of patients with ALL. Analysis of karyotypes in the total cohort of 625 patients. Percentages are given for each cytogenetic subgroup. BCR-ABL1 t(9;22)(q24;q11) translocation (n = 162), normal karyotype (n = 101), complex karyotype (≥4 aberrations) (n = 69), MYC-rearrangements (n = 40), high hyperdiploidy (51-68 chromosomes) (n = 38), MLL-rearrangements (n = 37), low hypodiploidy (<40 chromosomes) (n = 24), t(12;21)(p13;q22) (n = 15), and other cytogenetic abnormalities (n = 139).