[The value of Optical genome mapping technique for the verification of suspected chromosomal structural variations...

To assess the value of Optical genome mapping (OGM) for the verification of chromosomal structural variations among patients undergoing assisting reproduction.

A retrospective analysis was carried out on the clinical data of 12 patients presented at the Reproductive Center of Ningbo University Women and Children's Hospital from October 2022 to October 2024. All patients had undergone OGM testing due to suspection of structural variants by chromosomal karyotyping or a suggestive medical history. This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: EC2024-148).

Among the 12 patients verified by OGM, one (8.3%) was in keeping with the result of chromosomal karyotyping. Revised karyotypes were confirmed in seven cases (58.3%), including four with complex chromosomal rearrangements. Structural variation was excluded in three cases (25.0%). Of note, OGM has identified a previously undetected cryptic balanced translocation, i.e., ogm[GRCh38] t(7;12)(q36.3;q24.23)(157511190_157523142;119205703_119198409).

OGM can serve as an auxiliary diagnostic technique to conventional karyotyping and enable validation of suspected structural variations in those with ambiguous karyotype results or a history of adverse pregnancies. This can provide more precise genetic diagnosis for patients undergoing assisted reproduction and selection of clinical intervention strategies.