Figure 2.

Detection of mutations in three severe aplastic anemia subjects prior to clonal evolution. (A) Presence of NPM1 mutation detected by digital droplet PCR (ddPCR) at, and 2 years prior to, the diagnosis of clonal evolution in unique patient number (UPN)-1; (B) RUNX1 variant was found using ddPCR at, and 1 year before, the diagnosis of clonal evolution in UPN-2; (C) single-cell DNA sequencing at the time of clonal evolution in UPN-3 demonstrates that the successive acquisition of mutations over a 7-year period, including 2 years after the diagnosis of clonal evolution to a myeloid malignancy were all within the same clonal population. SAA: severe aplastic anemia; VAF: variant allele frequency.