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Hao N, Lou H, Li M, Zhang H, Chang J, Qi Q, Zhou X, Bai J, Guo J, Wang Y, Zhang Y, Jiang Y. Analysis of complex chromosomal rearrangement involving chromosome 6 via the integration of optical genomic mapping and molecular cytogenetic methodologies. J Hum Genet 2024; 69:3-11. [PMID: 37821671 DOI: 10.1038/s10038-023-01197-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 09/13/2023] [Accepted: 09/14/2023] [Indexed: 10/13/2023]
Abstract
Complex chromosomal rearrangements (CCRs) can result in spontaneous abortions, infertility, and malformations in newborns. In this study, we explored a familial CCR involving chromosome 6 by combining optical genomic mapping (OGM) and molecular cytogenetic methodologies. Within this family, the father and the paternal grandfather were both asymptomatic carriers of an identical balanced CCR, while the two offspring with an unbalanced paternal-origin CCR and two microdeletions presented with clinical manifestation. The first affected child, a 5-year-old boy, exhibited neurodevelopmental delay, while the second, a fetus, presented with hydrops fetalis. SNP-genotype analysis revealed a recombination event during gamete formation in the father that may have contributed to the deletion in his offspring. Meanwhile, the couple's haplotypes will facilitate the selection of normal gametes in the setting of assisted reproduction. Our study demonstrated the potential of OGM in identifying CCRs and its ability to work with current methodologies to refine precise breakpoints and construct accurate haplotypes for couples with a CCR.
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Affiliation(s)
- Na Hao
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric & Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | | | - Mengmeng Li
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric & Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Hanzhe Zhang
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric & Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Jiazhen Chang
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric & Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Qingwei Qi
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric & Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | - Xiya Zhou
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric & Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China
| | | | | | - Yaru Wang
- Ecobono (Beijing) Biotech Co., Ltd, Beijing, China
| | - Yanli Zhang
- Peking Jabrehoo Med Tech Co., Ltd, Beijing, China
| | - Yulin Jiang
- Department of Obstetrics and Gynecology, National Clinical Research Center for Obstetric & Gynecologic Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing, China.
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Xu P, Wang L, Li J, Huang S, Gao M, Kang R, Li J, Xie H, Liu X, Yan J, Gao X, Gao Y. OGM and WES identifies translocation breakpoints in PKD1 gene in an polycystic kidney patient and healthy baby delivered using PGT. BMC Med Genomics 2023; 16:285. [PMID: 37953234 PMCID: PMC10642002 DOI: 10.1186/s12920-023-01725-2] [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: 06/10/2023] [Accepted: 11/02/2023] [Indexed: 11/14/2023] Open
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common autosomal dominant genetic diseases. Whole exome sequencing (WES) is a routine tool for diagnostic confirmation of genetic diseases, and it is usually performed to confirm the clinical diagnosis in ADPKD. Reciprocal translocation is the most common chromosomal structural abnormalities and most of its carriers have normal phenotypes until they are encountered infertility problems in adulthood. However, for the polycystic kidney disease caused by abnormal chromosome structure, WES is difficult to achieve the purpose of gene diagnosis. METHODS ADPKD-related genes were detected by WES; Chromosomal karyotyping and Optical Genome Mapping (OGM) were used to detect structural variant; The genomic break-point locations and the abnormal splicing were detected by reverse transcription-PCR and Sanger sequencing; The karyomapping gene chip and Next-Generation Sequencing (NGS) were performed to screen aneuploidy and to distinguish the non-carrier embryos from the carrier embryos. RESULTS No pathogenic variant was found after the first round of WES analysis. Karyotyping data showed 46, XX, t (16; 17) (p13.3; q21.3). With the help of OGM, the translocation breakpoint on chromosome 16 was located within the PKD1 gene. With re-analysis of WES raw data, the breakpoint of translocation was verified to be located at the c.10618 + 3 of PKD1 gene. Based on this molecular diagnosis, a non-carrier embryo was selected out from three blastocysts. With preimplantation genetic testing (PGT) after in vitro fertilization (IVF), it was then transferred into uterus. With confirmation by prenatal and postnatal testing, the pedigree delivered a healthy baby. CONCLUSION We identified a case of ADPKD caused by balanced translocation and assisted the patient to have a healthy child. When the phenotype was closely related with a monogenic disease and the WES analysis was negative, chromosomal structural analysis would be recommended for further genetic diagnosis. Based on the precision diagnosis, preventing the recurrence of hereditary diseases in offspring would be reachable.
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Affiliation(s)
- Peiwen Xu
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Lijuan Wang
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Jing Li
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Sexin Huang
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Ming Gao
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Ranran Kang
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Jie Li
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Hongqiang Xie
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Xiaowei Liu
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Junhao Yan
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Xuan Gao
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China
| | - Yuan Gao
- Center for Reproductive Medicine, Cheeloo College of Medicine, Shandong University, Jinan, 250012, Shandong, China.
- Shandong Key Laboratory of Reproductive Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China.
- National Research Center for Assisted Reproductive Technology and Reproductive Genetics, Shandong University, Jinan, 250012, Shandong, China.
- Key laboratory of Reproductive Endocrinology of Ministry of Education, Shandong University, Jinan, 250012, Shandong, China.
- Shandong Provincial Clinical Medicine Research Center for Reproductive Health, Shandong University, Jinan, 250012, Shandong, China.
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Erbe LS, Hoffjan S, Janßen S, Kneifel M, Krause K, Gerding WM, Döring K, Güttsches AK, Roos A, Buena Atienza E, Gross C, Lücke T, Nguyen HHP, Vorgerd M, Köhler C. Exome Sequencing and Optical Genome Mapping in Molecularly Unsolved Cases of Duchenne Muscular Dystrophy: Identification of a Causative X-Chromosomal Inversion Disrupting the DMD Gene. Int J Mol Sci 2023; 24:14716. [PMID: 37834164 PMCID: PMC10572545 DOI: 10.3390/ijms241914716] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 09/25/2023] [Accepted: 09/26/2023] [Indexed: 10/15/2023] Open
Abstract
Duchenne muscular dystrophy (DMD) is a severe progressive muscle disease that mainly affects boys due to X-linked recessive inheritance. In most affected individuals, MLPA or sequencing-based techniques detect deletions, duplications, or point mutations in the dystrophin-encoding DMD gene. However, in a small subset of patients clinically diagnosed with DMD, the molecular cause is not identified with these routine methods. Evaluation of the 60 DMD patients in our center revealed three cases without a known genetic cause. DNA samples of these patients were analyzed using whole-exome sequencing (WES) and, if unconclusive, optical genome mapping (OGM). WES led to a diagnosis in two cases: one patient was found to carry a splice mutation in the DMD gene that had not been identified during previous Sanger sequencing. In the second patient, we detected two variants in the fukutin gene (FKTN) that were presumed to be disease-causing. In the third patient, WES was unremarkable, but OGM identified an inversion disrupting the DMD gene (~1.28 Mb) that was subsequently confirmed with long-read sequencing. These results highlight the importance of reanalyzing unsolved cases using WES and demonstrate that OGM is a useful method for identifying large structural variants in cases with unremarkable exome sequencing.
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Affiliation(s)
- Leoni S. Erbe
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
| | - Sabine Hoffjan
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
- Center for Rare Diseases Ruhr (CeSER), 44791 Bochum, Germany; (C.K.); (T.L.)
| | - Sören Janßen
- Department of Neuropediatrics, University Children’s Hospital, Ruhr-University Bochum, 44801 Bochum, Germany;
| | - Moritz Kneifel
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Karsten Krause
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Wanda M. Gerding
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
| | - Kristina Döring
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
| | - Anne-Katrin Güttsches
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Andreas Roos
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Elena Buena Atienza
- Institute of Medical Genetics and Applied Genomics, University Tübingen, 72074 Tübingen, Germany; (E.B.A.); (C.G.)
- NGS Competence Center Tübingen, 72076 Tübingen, Germany
| | - Caspar Gross
- Institute of Medical Genetics and Applied Genomics, University Tübingen, 72074 Tübingen, Germany; (E.B.A.); (C.G.)
- NGS Competence Center Tübingen, 72076 Tübingen, Germany
| | - Thomas Lücke
- Center for Rare Diseases Ruhr (CeSER), 44791 Bochum, Germany; (C.K.); (T.L.)
- Department of Neuropediatrics, University Children’s Hospital, Ruhr-University Bochum, 44801 Bochum, Germany;
| | - Hoa Huu Phuc Nguyen
- Department of Human Genetics, Ruhr-University Bochum, 44801 Bochum, Germany; (L.S.E.); (W.M.G.); (K.D.); (H.H.P.N.)
- Center for Rare Diseases Ruhr (CeSER), 44791 Bochum, Germany; (C.K.); (T.L.)
| | - Matthias Vorgerd
- Department of Neurology, Heimer Institute for Muscle Research, University Hospital Bergmannsheil, Ruhr-University Bochum, 44801 Bochum, Germany; (M.K.); (K.K.); (A.-K.G.); (A.R.); (M.V.)
| | - Cornelia Köhler
- Center for Rare Diseases Ruhr (CeSER), 44791 Bochum, Germany; (C.K.); (T.L.)
- Department of Neuropediatrics, University Children’s Hospital, Ruhr-University Bochum, 44801 Bochum, Germany;
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Lu YT, Rejiepu B, Zhang D, Cai DC, Yang KQ, Tian T, Zhou XL, Fan P. Childhood-Onset Refractory Hypertension Results from Neurofibromatosis Type 1 Caused by a Splicing NF1 Mutation. Kidney Blood Press Res 2023; 48:568-577. [PMID: 37562365 PMCID: PMC10614435 DOI: 10.1159/000533144] [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: 04/08/2023] [Accepted: 07/19/2023] [Indexed: 08/12/2023] Open
Abstract
INTRODUCTION Neurofibromatosis type 1 (NF-1) is caused by mutations in the NF1 gene that encodes neurofibromin, a negative regulator of RAS proto-oncogene. Approximately one-third of the reported pathogenic mutations in NF1 are splicing mutations, but most consequences are unclear. The objective of this study was to identify the pathogenicity of splicing mutation in a Chinese family with NF-1 and determine the effects of the pre-mRNA splicing mutation by in vitro functional analysis. METHODS Next-generation sequencing was used to screen candidate mutations. We performed a minigene splicing assay to determine the effect of the splicing mutation on NF1 expression, and three-dimensional structure models of neurofibromin were generated using SWISS-MODEL and PROCHECK methods, respectively. RESULTS A pathogenic splicing mutation c.479+1G>C in NF1 was found in the proband characterized by childhood-onset refractory hypertension. In vitro analysis demonstrated that c.479+1G>C mutation caused the skipping of exon 4, leading to a glutamine-to-valine substitution at position 97 in neurofibromin and an open reading frame shift terminating at codon 108. Protein modeling showed that several major domains were missing in the truncated neurofibromin protein. CONCLUSION The splicing mutation c.479+1G>C identified in a Chinese patient with NF-1 and childhood-onset refractory hypertension caused the skipping of exon 4 and a truncated protein. Our findings offer new evidence for the molecular diagnosis of NF-1.
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Affiliation(s)
- Yi-Ting Lu
- Department of Cardiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Buweimairemu Rejiepu
- Department of Cardiac Surgery, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China
| | - Di Zhang
- Department of Cardiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Dong-Cheng Cai
- Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Kun-Qi Yang
- Department of Cardiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Tao Tian
- Department of Cardiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Xian-Liang Zhou
- Department of Cardiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Peng Fan
- Department of Cardiology, Fuwai Hospital, National Center for Cardiovascular Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Alesi V, Genovese S, Lepri FR, Catino G, Loddo S, Orlando V, Di Tommaso S, Morgia A, Martucci L, Di Donato M, Digilio MC, Dallapiccola B, Novelli A, Capolino R. Deep Intronic LINE-1 Insertions in NF1: Expanding the Spectrum of Neurofibromatosis Type 1-Associated Rearrangements. Biomolecules 2023; 13:biom13050725. [PMID: 37238595 DOI: 10.3390/biom13050725] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2023] [Revised: 04/20/2023] [Accepted: 04/21/2023] [Indexed: 05/28/2023] Open
Abstract
Neurofibromatosis type 1 is an autosomal-dominant condition caused by NF1 gene inactivation. Clinical diagnosis is corroborated by genetic tests on gDNA and cDNA, which are inconclusive in approximately 3-5% of cases. Genomic DNA approaches may overlook splicing-affecting intronic variants and structural rearrangements, especially in regions enriched in repetitive sequences. On the other hand, while cDNA-based methods provide direct information about the effect of a variant on gene transcription, they are hampered by non-sense-mediated mRNA decay and skewed or monoallelic expression. Moreover, analyses on gene transcripts in some patients do not allow tracing back to the causative event, which is crucial for addressing genetic counselling, prenatal monitoring, and developing targeted therapies. We report on a familial NF1, caused by an insertion of a partial LINE-1 element inside intron 15, leading to exon 15 skipping. Only a few cases of LINE-1 insertion have been reported so far, hampering gDNA studies because of their size. Often, they result in exon skipping, and their recognition of cDNA may be difficult. A combined approach, based on Optical Genome Mapping, WGS, and cDNA studies, enabled us to detect the LINE-1 insertion and test its effects. Our results improve knowledge of the NF1 mutational spectrum and highlight the importance of custom-built approaches in undiagnosed patients.
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Affiliation(s)
- Viola Alesi
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Silvia Genovese
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Francesca Romana Lepri
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Giorgia Catino
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Sara Loddo
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Valeria Orlando
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Silvia Di Tommaso
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Alessandra Morgia
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Licia Martucci
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Maddalena Di Donato
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Maria Cristina Digilio
- Medical Genetics Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
- Genetics and Rare Disease Research Division, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Bruno Dallapiccola
- Genetics and Rare Disease Research Division, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Antonio Novelli
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
| | - Rossella Capolino
- Medical Genetics Unit, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
- Genetics and Rare Disease Research Division, Bambino Gesù Children Hospital, IRCCS, 00146 Rome, Italy
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6
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Pacot L, Chansavang A, Jacques S, Laurendeau I, Hadjadj D, Ferkal S, Wolkenstein P, Vidaud D, Pasmant E. Comment on Intragenic inversions in NF1 gene as pathogenic mechanism in neurofibromatosis type 1. Eur J Hum Genet 2023; 31:380-382. [PMID: 36732663 PMCID: PMC10133445 DOI: 10.1038/s41431-023-01304-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 01/26/2023] [Indexed: 02/04/2023] Open
Affiliation(s)
- Laurence Pacot
- Fédération de Génétique et Médecine Génomique, Hôpital Cochin, DMU BioPhyGen, AP-HP.Centre-Université Paris Cité, Paris, France
- Institut Cochin, Inserm U1016, CNRS UMR8104, Université Paris Cité, CARPEM, Paris, France
| | - Albain Chansavang
- Fédération de Génétique et Médecine Génomique, Hôpital Cochin, DMU BioPhyGen, AP-HP.Centre-Université Paris Cité, Paris, France
- Institut Cochin, Inserm U1016, CNRS UMR8104, Université Paris Cité, CARPEM, Paris, France
| | - Sébastien Jacques
- Institut Cochin, Inserm U1016, CNRS UMR8104, Université Paris Cité, CARPEM, Paris, France
| | - Ingrid Laurendeau
- Fédération de Génétique et Médecine Génomique, Hôpital Cochin, DMU BioPhyGen, AP-HP.Centre-Université Paris Cité, Paris, France
| | - Djihad Hadjadj
- Fédération de Génétique et Médecine Génomique, Hôpital Cochin, DMU BioPhyGen, AP-HP.Centre-Université Paris Cité, Paris, France
| | - Salah Ferkal
- Department of Dermatology, Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris (AP-HP), Créteil, France
- INSERM, Centre d'Investigation Clinique 1430, Hôpital Henri-Mondor, Assistance Publique-Hôpitaux de Paris (AP-HP), Referral Center of Neurofibromatosis, Créteil, France
| | - Pierre Wolkenstein
- Department of Dermatology, Hôpital Henri Mondor, Assistance Publique-Hôpitaux de Paris (AP-HP), Créteil, France
- INSERM, Centre d'Investigation Clinique 1430, Hôpital Henri-Mondor, Assistance Publique-Hôpitaux de Paris (AP-HP), Referral Center of Neurofibromatosis, Créteil, France
| | - Dominique Vidaud
- Fédération de Génétique et Médecine Génomique, Hôpital Cochin, DMU BioPhyGen, AP-HP.Centre-Université Paris Cité, Paris, France
- Institut Cochin, Inserm U1016, CNRS UMR8104, Université Paris Cité, CARPEM, Paris, France
| | - Eric Pasmant
- Fédération de Génétique et Médecine Génomique, Hôpital Cochin, DMU BioPhyGen, AP-HP.Centre-Université Paris Cité, Paris, France.
- Institut Cochin, Inserm U1016, CNRS UMR8104, Université Paris Cité, CARPEM, Paris, France.
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McNeill A. Genome sequencing-do you know what you are getting into? Eur J Hum Genet 2022; 30:1201-1202. [PMID: 36319748 PMCID: PMC9626481 DOI: 10.1038/s41431-022-01206-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Alisdair McNeill
- Department of Neuroscience, The University of Sheffield, Sheffield, UK.
- Sheffield Clinical Genetics Department, Sheffield Children's Hospital NHS Foundation Trust, Sheffield, UK.
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