In vivo and in vitro maintenance of the genetic heterogeneity of the original AML patient samples. Exome sequencing to determine variant allele frequency in the leukemic populations for 3 representative AML samples: A, #2; B, #1; and C, #3. Vertical axis shows the percentage of variant reads per allele, corresponding to different somatic mutations indicated in the key. Several samples from the same AML are depicted on the horizontal axis. All samples were sorted for huCD45 expression before sequencing. VAF of ∼50% indicates clonal mutations with most likely heterozygous configuration. VAF of ∼100% indicates clonal mutations with homozygous configuration, whereas frequencies lower than 50% show the presence of subclonal mutations.