This is also the case for genetic aberrations detected by reads that partially align to the GRCh38 genome such as junction reads and spanning fragments for detection of fusion transcripts, as well as SC reads for detection of long tandem duplications in FLT3 and KMT2A. While measurement of FLT3-ITD allelic ratios should be performed on DNA according to the ELN recommendations [1], a recent study in pediatric AML suggests measuring FLT3-ITD preferentially on RNA, since ITD expression is more strongly associated with poor overall survival than its presence per se [40]. The gene discussed is FLT3; the disease is acute myeloid leukemia.