Proof-of-concept study for the detection of somatic structural variant driver alterations using HiFi long-read sequencing in a pediatric leukemia cohort

Gene fusions are common primary drivers of pediatric leukemias and are the result of underlying structural variants (SVs). Current clinical workflows to detect such alterations rely on a multimodal approach, which often increases analysis time and overall cost of testing. In this study, we used long-read sequencing (lrSeq) as a proof-of-concept to determine whether clinically relevant (cr) SVs could be detected within a small (n = 17) pediatric leukemia cohort. We show that this methodology successfully determined all known crSVs (n = 5/5) detected through routine clinical testing. This approach also identified crSVs that resulted in the classification of a leukemia genetic subtype for four additional patients (n = 4/12), such as an ins(11;10)(q23.3;p12p12) forming a KMT2A::MLLT10 fusion, that were missed by routine clinical approaches. This study demonstrates the diagnostic potential of lrSeq as an assay for SV detection in pediatric leukemia and supports lrSeq as a valuable tool for the accurate detection of crSVs.