Clonal evolution of T-ALL during chemotherapy and at relapse. (A-C) The fish plot shows the clonal evolution in 3 T-ALL patients carrying multiple somatic mutations. Each color represents a clone, and the clone name (C1-Cn) matches the clones of Figure 2B. The number of mutations per clone is specified between brackets, and the set of mutations is shown for the major C1 clone and for clones with 1 mutation. For the genotype of all clones, please refer to Figure 2B. (A) Clonal evolution of XF97 patient from diagnosis (BM and PB) until MRD time point (5 weeks after diagnosis) showing a complete remission. (B) Clonal evolution of XF100 patient. Longitudinal single-cell analysis of 6 samples collected at 4 time points. The patient showed resistance to prednisone (high leukemia burden at T1) and showed residual leukemic cells at MRD time point (day 35 of treatment, end of the induction phase). (C) Clonal evolution of patient XD83 from diagnosis to relapse. XD83 showed distinct clonal compositions at diagnosis (BM), first relapse (BM and PB, 22.5 months after diagnosis), and second relapse (3.5 months after the first relapse). D1 and D2 nomenclature denote clones present at diagnosis whereas R2.1 and R2.2 are clones present at relapse 2.