Enrichment of MSI cells at relapse. (A) Patient L2: reconstructed lineage tree of CD117⁺, PB individual leukemia blasts cells at diagnosis (blue) and relapse (red) and CD34⁺ CD38⁻ CD90⁺ leukemia stem cells from bone marrow at diagnosis (orange) for patient L2. The dashed red line is the threshold above which cells are designated as MSI. Y-axis represents depth. The scale is the fraction of MSs with mutated allele divided by total number of MSs amplified for each cell. (B) CML blast crisis patient L5: reconstructed lineage tree of CD34⁺ CD117⁺ CD33⁺, from PB, individual leukemia blast cells at diagnosis (blue) and relapse (red) for patient L5. The dashed red line is the threshold above which cells are designated as MSI. Y-axis represents depth. The scale is the fraction of MSs with mutated allele divided by total number of MSs amplified for each cell.