PhD Scientific Days 2025

Poster Session II. - E: Pathological and Oncological Sciences

Analysis of bone marrow samples from multiple myeloma patients using optical genome mapping

Name of the presenter

Kardos Balázs

Institute/workplace of the presenter

Department of Pathology and Experimental Cancer Research

Authors

Balázs Kardos¹, Anna Bekő¹, Gábor Barna¹, Gergő Papp¹, Gábor Mikala², Gergely Varga³, Csaba Bödör¹

1: Department of Pathology and Experimental Cancer Research
2: DPC - National Institute of Haematology and Infectology
3: Department of Internal Medicine and Haematology

Text of the abstract

Introduction
Optical genome mapping (OGM) is a high-throughput cytogenetic assay that allows the accurate and reliable detection of structural variations (SV). This technology allows the detection of variations ranging from 500 base pairs to chromosome-wide sizes. OGM complements traditional cytogenetic methods such as FISH and karyotyping, while providing higher resolution and genome-wide coverage.
Aims
Our aim was to use OGM on bone marrow (BM) samples from multiple myeloma (MM) patients for the first time in the region to better understand the development and course of the disease.
Method
In our study, BM samples (diagnosis and relapse) from 18 MM patients were used, which were subjected to FISH analysis in addition to OGM. High-molecular-weight DNA was isolated and labeled with fluorescent dyes bound to specific sequence motifs. The samples were then loaded into the cells of the Bionano Saphyr chip and photographed by a high-resolution camera from these linear fibres. The resulting data were analysed using Bionano Solve software, which detected SV aligned to the reference genome. The resulting genomic maps were used to evaluate the genomic profile of the samples studied and to identify clinically relevant variations.
Results
BM samples from 18 patients have been analysed by OGM and compared with the results of FISH. All genetic abnormalities detected by FISH were detected by OGM, but in several cases additional abnormalities were detected. In one 65-year-old male patient, in addition to the IGH signal and del(1p12) abnormalities detected by FISH, we identified extensive IGH loss, t(9;14) translocation, and chromothripsis affecting chromosomes 3, 5, 15, and 19, in addition to aneuploidy affecting chromosome 9. After unsuccessful FISH in a 66-year-old male patient, we detected, among others, 1q21 gain, 1p12 loss, t(4;14) translocation, and hyperdiploidy affecting several chromosomes. And in a 75-year-old female patient, in addition to the t(4;14) translocation indicated by FISH, a t(8;14) mismatch was detected.
Conclusion
OGM is a reliable method for the detection of different cytogenetic abnormalities in MM. In the near future, it may be an efficient and rapid tool for the diagnosis of a wide variety of oncohematological diseases, complementing conventional cytogenetic procedures.
Funding
MTA Lendület (LP2024-3), HCEMM (SGA No. 739593), SE 250+