Comparison of Optical Genome Mapping With Conventional Diagnostic Methods for Structural Variant Detection in...

Area of Science:

• Genomics
• Molecular Diagnostics
• Hematologic Oncology

Background:

• Conventional methods for analyzing structural variants (SVs) in hematologic malignancies have limitations.
• Optical genome mapping (OGM) is an emerging single-molecule technology for SV detection with potential to replace conventional approaches.

Purpose of the Study:

• To compare the diagnostic utility of OGM with conventional methods for detecting SVs in hematologic malignancies.
• To evaluate the concordance rate between OGM and established diagnostic techniques.

Main Methods:

• Residual bone marrow aspirates from 27 patients with hematologic malignancies were analyzed using OGM.
• Conventional methods included chromosomal banding analysis, FISH, RNA fusion panel, and reverse transcription PCR.
• Concordance between OGM and conventional results was evaluated.

Main Results:

• OGM demonstrated concordance in 63% and partial concordance in 37% of samples.
• The overall correct detection rate for SVs by OGM was 76%, with high accuracy for aneuploidies, balanced translocations, deletions, duplications, inversions, and isochromosomes.
• Discordant results were linked to centromeric/telomeric regions, sensitivity, and mapping issues; OGM identified additional submicroscopic SVs and novel fusions in five cases.

Conclusions:

• OGM exhibits significant concordance with conventional methods for SV detection in hematologic malignancies.
• OGM has the potential for comprehensive SV analysis in routine diagnostics, including the identification of novel variants.
• Further studies and technological improvements are necessary to fully realize OGM's utility in clinical settings.