1
|
Wang Y, Wen X, Shen XM, Di L, Sun Y, Li Y, Zhang S, Wen Q, Wang J, Duo J, Huang Y, Lu Y, Xu M, Wang M, Chen H, Zhu W, Da Y. A rare complex structural variant of novel intragenic inversion combined with reciprocal translocation t(X;1)(p21.2;p13.3) in Duchenne muscular dystrophy. Neuromuscul Disord 2024; 39:24-29. [PMID: 38714145 DOI: 10.1016/j.nmd.2024.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 04/08/2024] [Accepted: 04/11/2024] [Indexed: 05/09/2024]
Abstract
Structural variants (SVs) are infrequently observed in Duchenne muscular dystrophy (DMD), a condition mainly marked by deletions and point mutations in the DMD gene. SVs in DMD remain difficult to reliably detect due to the limited SV-detection capacity of conventionally used short-read sequencing technology. Herein, we present a family, a boy and his mother, with clinical signs of muscular dystrophy, elevated creatinine kinase levels, and intellectual disability. A muscle biopsy from the boy showed dystrophin deficiency. Routine molecular techniques failed to detect abnormalities in the DMD gene, however, dystrophin mRNA transcripts analysis revealed an absence of exons 59 to 79. Subsequent long-read whole-genome sequencing identified a rare complex structural variant, a 77 kb novel intragenic inversion, and a balanced translocation t(X;1)(p21.2;p13.3) rearrangement within the DMD gene, expanding the genetic spectrum of dystrophinopathy. Our findings suggested that SVs should be considered in cases where conventional molecular techniques fail to identify pathogenic variants.
Collapse
Affiliation(s)
- Yaye Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Xinmei Wen
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Xin-Ming Shen
- Department of Neurology and Neuromuscular Research Laboratory, Mayo Clinic, Rochester, MN 55905, USA
| | - Li Di
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Yanan Sun
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Yun Li
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Shu Zhang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Qi Wen
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Jingsi Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Jianying Duo
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Yue Huang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Yan Lu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Min Xu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Min Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Hai Chen
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Wenjia Zhu
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China
| | - Yuwei Da
- Department of Neurology, Xuanwu Hospital, Capital Medical University, No. 45 Changchun Street, Xicheng District, Beijing 100053, China.
| |
Collapse
|
2
|
Ng KWP, Chin HL, Chin AXY, Goh DLM. Using gene panels in the diagnosis of neuromuscular disorders: A mini-review. Front Neurol 2022; 13:997551. [PMID: 36313509 PMCID: PMC9602396 DOI: 10.3389/fneur.2022.997551] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 09/21/2022] [Indexed: 09/26/2023] Open
Abstract
The diagnosis of inherited neuromuscular disorders is challenging due to their genetic and phenotypic variability. Traditionally, neurophysiology and histopathology were primarily used in the initial diagnostic approach to these conditions. Sanger sequencing for molecular diagnosis was less frequently utilized as its application was a time-consuming and cost-intensive process. The advent and accessibility of next-generation sequencing (NGS) has revolutionized the evaluation process of genetically heterogenous neuromuscular disorders. Current NGS diagnostic testing approaches include gene panels, whole exome sequencing (WES), and whole genome sequencing (WGS). Gene panels are often the most widely used, being more accessible due to availability and affordability. In this mini-review, we describe the benefits and risks of clinical genetic testing. We also discuss the utility, benefits, challenges, and limitations of using gene panels in the evaluation of neuromuscular disorders.
Collapse
Affiliation(s)
- Kay W. P. Ng
- Division of Neurology, Department of Medicine, National University Hospital, Singapore, Singapore
| | - Hui-Lin Chin
- Division of Genetics and Metabolism, Department of Paediatrics, Khoo Teck Puat - National University Children's Medical Institute, National University Hospital, Singapore, Singapore
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Amanda X. Y. Chin
- Division of Neurology, Department of Medicine, National University Hospital, Singapore, Singapore
| | - Denise Li-Meng Goh
- Division of Genetics and Metabolism, Department of Paediatrics, Khoo Teck Puat - National University Children's Medical Institute, National University Hospital, Singapore, Singapore
- Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| |
Collapse
|
3
|
Xie Z, Liu C, Lu Y, Sun C, Liu Y, Yu M, Shu J, Meng L, Deng J, Zhang W, Wang Z, Lv H, Yuan Y. Exonization of a deep intronic long interspersed nuclear element in Becker muscular dystrophy. Front Genet 2022; 13:979732. [PMID: 36092865 PMCID: PMC9453646 DOI: 10.3389/fgene.2022.979732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 07/25/2022] [Indexed: 11/28/2022] Open
Abstract
The precise identification of pathogenic DMD variants is sometimes rather difficult, mainly due to complex structural variants (SVs) and deep intronic splice-altering variants. We performed genomic long-read whole DMD gene sequencing in a boy with asymptomatic hyper-creatine kinase-emia who remained genetically undiagnosed after standard genetic testing, dystrophin protein and DMD mRNA studies, and genomic short-read whole DMD gene sequencing. We successfully identified a novel pathogenic SV in DMD intron 1 via long-read sequencing. The deep intronic SV consists of a long interspersed nuclear element-1 (LINE-1) insertion/non-tandem duplication rearrangement causing partial exonization of the LINE-1, establishing a genetic diagnosis of Becker muscular dystrophy. Our study expands the genetic spectrum of dystrophinopathies and highlights the significant role of disease-causing LINE-1 insertions in monogenic diseases.
Collapse
Affiliation(s)
- Zhiying Xie
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Chang Liu
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Yanyu Lu
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Chengyue Sun
- Department of Neurology, Peking University People’s Hospital, Beijing, China
| | - Yilin Liu
- Department of Pathology, Peking Union Medical College Hospital, Beijing, China
| | - Meng Yu
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Junlong Shu
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Lingchao Meng
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Jianwen Deng
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Wei Zhang
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - Zhaoxia Wang
- Department of Neurology, Peking University First Hospital, Beijing, China
| | - He Lv
- Department of Neurology, Peking University First Hospital, Beijing, China
- *Correspondence: Yun Yuan, ; He Lv,
| | - Yun Yuan
- Department of Neurology, Peking University First Hospital, Beijing, China
- *Correspondence: Yun Yuan, ; He Lv,
| |
Collapse
|