A Canadian tertiary-care study found optical genome mapping (OGM) identified additional clinically relevant structural variants in nearly 20% of acute leukemia cases when used as a first-line test. Published in The Journal of Molecular Diagnostics, the work evaluated OGM against standard cytogenetics and highlighted its potential to streamline and enhance diagnostic yield. Investigators reported OGM detected cryptic rearrangements and copy-number changes missed by conventional methods, with implications for diagnosis, prognosis, and therapy selection. The authors argue for consideration of OGM integration into diagnostic workflows to reduce missed variants and accelerate treatment decisions. Clarification: Optical genome mapping is a high-resolution method that visualizes long DNA molecules to reveal structural variants—rearrangements, insertions, deletions and copy-number changes—often undetectable by short-read sequencing or standard karyotyping.