Assessing Genomic Aberrations in AML using Optical Genome Mapping: Insights from a National Multi-Center Study

A recent national multi-institutional study assessed the performance, in a real-world setting, of optical genome mapping (OGM) in a cohort of 100 AML cases. The results revealed that OGM effectively recovers clinically relevant balanced structural variants (SVs) and copy number changes found by standard of care methods such as karyotyping, fluorescence in situ hybridization (FISH) and chromosomal microarray analysis (CMA). Importantly, OGM identified clinically relevant SVs in 11% of cases that had been missed by the routine methods and refined the underlying genomic structure reported by traditional cytogenomic testing in 13% of cases. The ability to detect cryptic translocations in an unbiased manner was a highlighted by the study with 3 cases reported with normal karyotypes shown to have cryptic translocations involving gene fusions. Some of these findings would have altered recommended clinical management or rendered the case eligible for clinical trials. The ability of OGM to yield results in a single assay analogous to those attainable from three separate assays (karyotyping, FISH, CMA) demonstrated that OGM can potentially eliminate the requirement for multiple labor-intensive cytogenetic tests while concomitantly maximizing diagnostic detection through a standardized workflow.