20.500.12556/DiRROS-24537 Value of optical genome mapping (OGM) for diagnostics of rare diseases a family case report Optical genome mapping (OGM) is a novel method enabling the detection of structural genomic variants. The method is based on the laser image acquisition of single, labeled, high-molecular-weight DNA molecules and can detect structural genomic variants such as translocations, inversions, insertions, deletions, duplications, and complex structural rearrangements. We aim to present our experience with OGM at the Clinical Institute of Genomic Medicine, University Medical Centre Ljubljana, Slovenia. Since its introduction in 2021, we have used OGM for the testing of facioscapulohumeral muscular dystrophy 1, characterization and resolution of variants identified by other technologies such as microarrays, exome and genome next-generation sequencing, karyotyping, as well as testing of rare disease patients in whom no genetic cause could be identified using these methods. We present an example family case of two previously undiagnosed male siblings with an overlapping clinical presentation of thrombocytopenia, obesity, and presacral teratoma. After karyotyping, microarray analysis and next-generation sequencing, by using OGM, a maternally inherited cryptic translocation t(X;18)(q27.1;q12.2) was identified in both brothers. Despite an extended segregation analysis, based on strictly applied ACMG criteria and ClinGen guidelines, the identified translocation remains a variant of unknown significance. Despite the remaining limitations of OGM, which will hopefully be resolved by improvements in databases of known benign SV variation and the establishment of official guidelines on the clinical interpretation of OGM variants, our work highlights the complexity of the diagnostic journey, including this novel method, in rare disease cases. optical genome mapping OGM structural variants SV genomic variants rare disease genetic testing optično genomsko mapiranje redke bolezni genetika genomika true false true Angleški jezik Slovenski jezik Neznano 2025-12-04 13:46:18 2025-12-04 13:46:19 2025-12-06 03:41:11 0000-00-00 00:00:00 2024 0 0 Nasl. z nasl. zaslona; Opis vira z dne 26. 5. 2025; str. 87-93 iss. 2 Vol. 27 Dec. 2024 0000-00-00 Zaloznikova Objavljeno apc 0000-00-00 0000-00-00 0000-00-00 61:575.111 2199-5761 10.2478/bjmg-2024-0021 237203715 RAZ_Kovanda_Anja_2024.pdf RAZ_Kovanda_Anja_2024.pdf 1 B3C89C42839537C5A32867367C08F7D9 ab77c7b580eb5bacccad4412e597ba4de8da12e3a25bbb940852a59af219379f e5ac38f8-d10f-11f0-94a7-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=36593 https://reference-global.com/article/10.2478/bjmg-2024-0021 0 3d41e65f-d10f-11f0-94a7-001a4af901a5 https://dirros.openscience.si/Dokument.php?lang=slv&id=36591 Univerzitetni klinični center Ljubljana 0 0 0