TY - JOUR T1 - Detection of cryptic balanced chromosomal rearrangements using high-resolution optical genome mapping JF - Journal of Medical Genetics JO - J Med Genet SP - 274 LP - 284 DO - 10.1136/jmedgenet-2022-108553 VL - 60 IS - 3 AU - Shuo Zhang AU - Zhenle Pei AU - Caixia Lei AU - Saijuan Zhu AU - Ke Deng AU - Jing Zhou AU - Jingmin Yang AU - Daru Lu AU - Xiaoxi Sun AU - Chenming Xu AU - Congjian Xu Y1 - 2023/03/01 UR - http://jmg.bmj.com/content/60/3/274.abstract N2 - Background Chromosomal rearrangements have profound consequences in diverse human genetic diseases. Currently, the detection of balanced chromosomal rearrangements (BCRs) mainly relies on routine cytogenetic G-banded karyotyping. However, cryptic BCRs are hard to detect by karyotyping, and the risk of miscarriage or delivering abnormal offspring with congenital malformations in carrier couples is significantly increased. In the present study, we aimed to investigate the potential of single-molecule optical genome mapping (OGM) in unravelling cryptic chromosomal rearrangements.Methods Eleven couples with normal karyotypes that had abortions/affected offspring with unbalanced rearrangements were enrolled. Ultra-high-molecular-weight DNA was isolated from peripheral blood cells and processed via OGM. The genome assembly was performed followed by variant calling and annotation. Meanwhile, multiple detection strategies, including FISH, long-range-PCR amplicon-based next-generation sequencing and Sanger sequencing were implemented to confirm the results obtained from OGM.Results High-resolution OGM successfully detected cryptic reciprocal translocation in all recruited couples, which was consistent with the results of FISH and sequencing. All high-confidence cryptic chromosomal translocations detected by OGM were confirmed by sequencing analysis of rearrangement breakpoints. Moreover, OGM revealed additional complex rearrangement events such as inverted aberrations, further refining potential genetic interpretation.Conclusion To the best of our knowledge, this is the first study wherein OGM facilitate the rapid and robust detection of cryptic chromosomal reciprocal translocations in clinical practice. With the excellent performance, our findings suggest that OGM is well qualified as an accurate, comprehensive and first-line method for detecting cryptic BCRs in routine clinical testing.The original contributions presented in the study are included in the article/Supplemental Materials, further inquiries can be directed to the corresponding author/s. ER -