1
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Maver A, Lohmann K, Borovečki F, Wolstenholme N, Taylor RL, Spielmann M, Haack TB, Gerberding M, Peterlin B, Graessner H. Quality assurance for next-generation sequencing diagnostics of rare neurological diseases in the European Reference Network. Eur J Hum Genet 2024:10.1038/s41431-024-01639-2. [PMID: 38839988 DOI: 10.1038/s41431-024-01639-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/26/2024] [Accepted: 05/14/2024] [Indexed: 06/07/2024] Open
Abstract
In the past decade, next-generation sequencing (NGS) has revolutionised genetic diagnostics for rare neurological disorders (RND). However, the lack of standardised technical, interpretative, and reporting standards poses a challenge for ensuring consistent and high-quality diagnostics globally. To address this, the European Reference Network for Rare Neurological Diseases (ERN-RND) collaborated with the European Molecular Genetics Quality Network (EMQN) to establish an external quality assessment scheme for NGS-based diagnostics in RNDs. The scheme, initiated in 2021 with a pilot involving 29 labs and followed by a second round in 2022 with 42 labs, aimed to evaluate the performance of laboratories in genetic testing for RNDs. Each participating lab analysed genetic data from three hypothetical cases, assessing genotyping, interpretation, and clerical accuracy. Despite a majority of labs using exome or genome sequencing, there was considerable variability in gene content, sequencing quality, adherence to standards, and clinical guidance provision. Results showed that while most labs provided correct molecular diagnoses, there was significant variability in reporting technical quality, adherence to interpretation standards, reporting strategies, and clinical commentary. Notably, some labs returned results with the potential for adverse medical outcomes. This underscores the need for further harmonisation, guideline development, and external quality assessment in the evolving landscape of genomic diagnostics for RNDs. Overall, the experience with the scheme highlighted the generally good quality of participating labs but emphasised the imperative for ongoing improvement in data analysis, interpretation, and reporting to enhance patient safety.
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Affiliation(s)
- Aleš Maver
- Clinical Institute of Genomic Medicine, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Katja Lohmann
- Institute of Neurogenetics, University of Luebeck, Luebeck, Germany
| | - Fran Borovečki
- Department of Neurology, University Hospital Centre Zagreb, Zagreb, Croatia
| | | | - Rachel L Taylor
- EMQN CIC, Unit 4 Enterprise Hse, Manchester Science Park, Manchester, UK
| | - Malte Spielmann
- Institute of Human Genetics, University of Lübeck, Lübeck, Germany
| | - Tobias B Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Matthias Gerberding
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany
| | - Borut Peterlin
- Clinical Institute of Genomic Medicine, University Medical Centre Ljubljana, Ljubljana, Slovenia
| | - Holm Graessner
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, Tübingen, Germany.
- Centre for Rare Diseases, University of Tübingen, Tübingen, Germany.
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2
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Zhang H, Andreou A, Bhatt R, Whitworth J, Yngvadottir B, Maher ER. Characteristics, aetiology and implications for management of multiple primary renal tumours: a systematic review. Eur J Hum Genet 2024:10.1038/s41431-024-01628-5. [PMID: 38802529 DOI: 10.1038/s41431-024-01628-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 04/16/2024] [Accepted: 05/01/2024] [Indexed: 05/29/2024] Open
Abstract
In a subset of patients with renal tumours, multiple primary lesions may occur. Predisposition to multiple primary renal tumours (MPRT) is a well-recognised feature of some inherited renal cancer syndromes. The diagnosis of MPRT should therefore provoke a thorough assessment for clinical and genetic evidence of disorders associated with predisposition to renal tumourigenesis. To better define the clinical and genetic characteristics of MPRT, a systematic literature review was performed for publications up to 3 April 2024. A total of 7689 patients from 467 articles were identified with MPRT. Compared to all patients with renal cell carcinoma (RCC), patients with MPRT were more likely to be male (71.8% versus 63%) and have an earlier age at diagnosis (<46 years, 32.4% versus 19%). In 61.1% of cases MPRT were synchronous. The proportion of cases with similar histology and the proportion of cases with multiple papillary renal cell carcinoma (RCC) (16.1%) were higher than expected. In total, 14.9% of patients with MPRT had a family history of cancer or were diagnosed with a hereditary RCC associated syndrome with von Hippel-Lindau (VHL) disease being the most common one (69.7%), followed by Birt-Hogg-Dubé (BHD) syndrome (14.2%). Individuals with a known or likely genetic cause were, on average, younger (43.9 years versus 57.1 years). In rare cases intrarenal metastatic RCC can phenocopy MPRT. We review potential genetic causes of MPRT and their implications for management, suggest an approach to genetic testing for individuals presenting with MPRT and considerations in cases in which routine germline genetic testing does not provide a diagnosis.
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Affiliation(s)
- Huairen Zhang
- Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Avgi Andreou
- Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Rupesh Bhatt
- Department of Urology, Queen Elizabeth Hospital, Birmingham, B15, UK
| | - James Whitworth
- Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Bryndis Yngvadottir
- Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK
| | - Eamonn R Maher
- Department of Medical Genetics, School of Clinical Medicine, University of Cambridge, Cambridge, CB2 0QQ, UK.
- Aston Medical School, College of Health and Life Sciences, Aston University, Birmingham, B4 7ET, UK.
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3
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Stojkic I, Prince BT, Kuehn HS, Gil Silva AA, Varga EA, Rosenzweig SD, Ramadesikan S, Supinger R, Marhabaie M, Chang P, Mardis ER, Koboldt DC. A novel IKZF1 variant in a family with autosomal dominant CVID: A case for expanding exon coverage in inborn errors of immunity. Clin Immunol 2024; 264:110244. [PMID: 38734037 DOI: 10.1016/j.clim.2024.110244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Revised: 05/01/2024] [Accepted: 05/02/2024] [Indexed: 05/13/2024]
Abstract
Common variable immune deficiency (CVID) is a heterogenous group of disorders characterized by varying degrees of hypogammaglobulinemia, recurrent infections, and autoimmunity. Currently, pathogenic variants are identified in approximately 20-30% of CVID cases. Here we report a 3-generation family with autosomal dominant Common Variable Immunodeficiency (CVID) diagnosed in 9 affected individuals. Although primary immune deficiency panels and exome sequencing were non-diagnostic, whole genome sequencing revealed a novel, pathogenic c.499C > T: p.His167Tyr variant in IKZF1, a critical regulator of B cell development. Functional testing done through pericentromeric heterochromatin localization and light shift chemiluminescent electrophoretic mobility shift assay confirmed the variant's deleterious effect via a haploinsufficiency mechanism. Our findings expand the spectrum of known IKZF1 mutations and contribute to a more comprehensive understanding of CVID's genetic heterogeneity. Furthermore, this case underscores the importance of considering whole genome sequencing for comprehensive genetic diagnosis when concern for a monogenic inborn errors of immunity is high.
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Affiliation(s)
- Ivana Stojkic
- Division of Pediatric Rheumatology, Nationwide Children's Hospital, Columbus, OH, USA.
| | - Benjamin T Prince
- Division of Allergy and Immunology, Nationwide Children's Hospital, Columbus, OH, USA
| | - Hye Sun Kuehn
- Immunology Service, Department of Laboratory Medicine, National Institutes of Health Clinical Center, NIH, Bethesda, MD, USA
| | - Agustin A Gil Silva
- Immunology Service, Department of Laboratory Medicine, National Institutes of Health Clinical Center, NIH, Bethesda, MD, USA
| | - Elizabeth A Varga
- Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Sergio D Rosenzweig
- Immunology Service, Department of Laboratory Medicine, National Institutes of Health Clinical Center, NIH, Bethesda, MD, USA
| | - Swetha Ramadesikan
- Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Rachel Supinger
- Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Mohammad Marhabaie
- Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Peter Chang
- Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Elaine R Mardis
- Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
| | - Daniel C Koboldt
- Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
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4
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Ma H, Zhu L, Yang X, Ao M, Zhang S, Guo M, Dai X, Ma X, Zhang X. Genetic and phenotypic analysis of 225 Chinese children with developmental delay and/or intellectual disability using whole-exome sequencing. BMC Genomics 2024; 25:391. [PMID: 38649797 PMCID: PMC11034079 DOI: 10.1186/s12864-024-10279-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2023] [Accepted: 04/02/2024] [Indexed: 04/25/2024] Open
Abstract
Developmental delay (DD), or intellectual disability (ID) is a very large group of early onset disorders that affects 1-2% of children worldwide, which have diverse genetic causes that should be identified. Genetic studies can elucidate the pathogenesis underlying DD/ID. In this study, whole-exome sequencing (WES) was performed on 225 Chinese DD/ID children (208 cases were sequenced as proband-parent trio) who were classified into seven phenotype subgroups. The phenotype and genomic data of patients with DD/ID were further retrospectively analyzed. There were 96/225 (42.67%; 95% confidence interval [CI] 36.15-49.18%) patients were found to have causative single nucleotide variants (SNVs) and small insertions/deletions (Indels) associated with DD/ID based on WES data. The diagnostic yields among the seven subgroups ranged from 31.25 to 71.43%. Three specific clinical features, hearing loss, visual loss, and facial dysmorphism, can significantly increase the diagnostic yield of WES in patients with DD/ID (P = 0.005, P = 0.005, and P = 0.039, respectively). Of note, hearing loss (odds ratio [OR] = 1.86%; 95% CI = 1.00-3.46, P = 0.046) or abnormal brainstem auditory evoked potential (BAEP) (OR = 1.91, 95% CI = 1.02-3.50, P = 0.042) was independently associated with causative genetic variants in DD/ID children. Our findings enrich the variation spectrums of SNVs/Indels associated with DD/ID, highlight the value genetic testing for DD/ID children, stress the importance of BAEP screen in DD/ID children, and help to facilitate early diagnose, clinical management and reproductive decisions, improve therapeutic response to medical treatment.
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Affiliation(s)
- Heqian Ma
- The School of Public Health, Guilin Medical University, 1 Zhiyuan Road, Lingui District, 541199, Guilin, PR China
| | - Lina Zhu
- Faculty of Pediatrics, The Chinese PLA General Hospital, 100700, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, 100700, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, 100700, Beijing, China
| | - Xiao Yang
- Faculty of Pediatrics, The Chinese PLA General Hospital, 100700, Beijing, China
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, 100700, Beijing, China
- Beijing Key Laboratory of Pediatric Organ Failure, 100700, Beijing, China
| | - Meng Ao
- The School of Public Health, Guilin Medical University, 1 Zhiyuan Road, Lingui District, 541199, Guilin, PR China
| | - Shunxiang Zhang
- The School of Public Health, Guilin Medical University, 1 Zhiyuan Road, Lingui District, 541199, Guilin, PR China
| | - Meizhen Guo
- The School of Public Health, Guilin Medical University, 1 Zhiyuan Road, Lingui District, 541199, Guilin, PR China
| | - Xuelin Dai
- The School of Public Health, Guilin Medical University, 1 Zhiyuan Road, Lingui District, 541199, Guilin, PR China
| | - Xiuwei Ma
- Faculty of Pediatrics, The Chinese PLA General Hospital, 100700, Beijing, China.
- National Engineering Laboratory for Birth Defects Prevention and Control of Key Technology, 100700, Beijing, China.
- Beijing Key Laboratory of Pediatric Organ Failure, 100700, Beijing, China.
| | - Xiaoying Zhang
- The School of Public Health, Guilin Medical University, 1 Zhiyuan Road, Lingui District, 541199, Guilin, PR China.
- The Guangxi Key Laboratory of Environmental Exposomics and Entire Lifecycle Heath, 1 Zhiyuan Road, Lingui District, 541199, Guilin, PR China.
- Guangxi Health Commission Key Laboratory of Entire Lifecycle Health and Care, 1 Zhiyuan Road, Lingui District, 541199, Guilin, PR China.
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5
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Alamri N, Lanktree MB. Large Kidney Cysts in HNF1B Nephropathy Mimicking Autosomal Dominant Polycystic Kidney Disease. Can J Kidney Health Dis 2024; 11:20543581241232470. [PMID: 38370308 PMCID: PMC10874158 DOI: 10.1177/20543581241232470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 01/10/2024] [Indexed: 02/20/2024] Open
Abstract
Rationale Hepatocyte nuclear factor 1 beta (HNF1B) nephropathy is a rare autosomal dominant monogenic kidney disease. We present a case mimicking autosomal dominant polycystic kidney disease (ADPKD), highlighting the phenotypic heterogeneity of HNF1B-related disease. Presenting concerns of the patient A 37-year-old man presented with hypertensive urgency, accompanied by flank pain and abdominal distension. Despite the absence of familial kidney disease, imaging revealed large bilateral kidney cysts resembling ADPKD. Diagnosis We initially suspected de novo ADPKD. However, negative genetic testing results for PKD1 and PKD2 led to a 43-gene cystic kidney sequencing panel which identified a deletion encompassing the entire HNF1B gene. Intervention To alleviate discomfort caused by the kidney cysts, ultrasound-guided aspiration and foam sclerotherapy were performed. Tolvaptan, used for treating high-risk ADPKD, was not prescribed after confirming the diagnosis was HNF1B nephropathy. Outcomes A diagnosis of HNF1B nephropathy was reached following gene panel testing. Abdominal symptoms improved following cyst aspiration and foam sclerotherapy. Novel findings HNF1B nephropathy has a variable presentation but can lead to cysts appearing like ADPKD. A 43-gene cystic kidney sequencing panel identified the diagnosis in this uncertain case.
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Affiliation(s)
- Nada Alamri
- Department of Medicine, McMaster University, Hamilton, ON, Canada
| | - Matthew B. Lanktree
- Department of Medicine, McMaster University, Hamilton, ON, Canada
- Department of Health Research Methods, Evidence & Impact, McMaster University, Hamilton, ON, Canada
- Population Health Research Institute, Hamilton, ON, Canada
- Division of Nephrology, St. Joseph’s Healthcare Hamilton, Hamilton, ON, Canada
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6
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Schobers G, Derks R, den Ouden A, Swinkels H, van Reeuwijk J, Bosgoed E, Lugtenberg D, Sun SM, Corominas Galbany J, Weiss M, Blok MJ, Olde Keizer RACM, Hofste T, Hellebrekers D, de Leeuw N, Stegmann A, Kamsteeg EJ, Paulussen ADC, Ligtenberg MJL, Bradley XZ, Peden J, Gutierrez A, Pullen A, Payne T, Gilissen C, van den Wijngaard A, Brunner HG, Nelen M, Yntema HG, Vissers LELM. Genome sequencing as a generic diagnostic strategy for rare disease. Genome Med 2024; 16:32. [PMID: 38355605 PMCID: PMC10868087 DOI: 10.1186/s13073-024-01301-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Accepted: 02/02/2024] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND To diagnose the full spectrum of hereditary and congenital diseases, genetic laboratories use many different workflows, ranging from karyotyping to exome sequencing. A single generic high-throughput workflow would greatly increase efficiency. We assessed whether genome sequencing (GS) can replace these existing workflows aimed at germline genetic diagnosis for rare disease. METHODS We performed short-read GS (NovaSeq™6000; 150 bp paired-end reads, 37 × mean coverage) on 1000 cases with 1271 known clinically relevant variants, identified across different workflows, representative of our tertiary diagnostic centers. Variants were categorized into small variants (single nucleotide variants and indels < 50 bp), large variants (copy number variants and short tandem repeats) and other variants (structural variants and aneuploidies). Variant calling format files were queried per variant, from which workflow-specific true positive rates (TPRs) for detection were determined. A TPR of ≥ 98% was considered the threshold for transition to GS. A GS-first scenario was generated for our laboratory, using diagnostic efficacy and predicted false negative as primary outcome measures. As input, we modeled the diagnostic path for all 24,570 individuals referred in 2022, combining the clinical referral, the transition of the underlying workflow(s) to GS, and the variant type(s) to be detected. RESULTS Overall, 95% (1206/1271) of variants were detected. Detection rates differed per variant category: small variants in 96% (826/860), large variants in 93% (341/366), and other variants in 87% (39/45). TPRs varied between workflows (79-100%), with 7/10 being replaceable by GS. Models for our laboratory indicate that a GS-first strategy would be feasible for 84.9% of clinical referrals (750/883), translating to 71% of all individuals (17,444/24,570) receiving GS as their primary test. An estimated false negative rate of 0.3% could be expected. CONCLUSIONS GS can capture clinically relevant germline variants in a 'GS-first strategy' for the majority of clinical indications in a genetics diagnostic lab.
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Affiliation(s)
- Gaby Schobers
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands
| | - Ronny Derks
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
| | - Amber den Ouden
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
| | - Hilde Swinkels
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
| | - Jeroen van Reeuwijk
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands
| | - Ermanno Bosgoed
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
| | | | - Su Ming Sun
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, Netherlands
| | - Jordi Corominas Galbany
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands
| | - Marjan Weiss
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
| | - Marinus J Blok
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, Netherlands
| | - Richelle A C M Olde Keizer
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands
| | - Tom Hofste
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
| | - Debby Hellebrekers
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, Netherlands
| | - Nicole de Leeuw
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
| | - Alexander Stegmann
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, Netherlands
| | | | - Aimee D C Paulussen
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, Netherlands
| | - Marjolijn J L Ligtenberg
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands
| | | | | | | | | | | | - Christian Gilissen
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands
| | | | - Han G Brunner
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands
- Department of Clinical Genetics, Maastricht University Medical Center, Maastricht, Netherlands
| | - Marcel Nelen
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
| | - Helger G Yntema
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands
| | - Lisenka E L M Vissers
- Department of Human Genetics, Radboudumc, Nijmegen, Netherlands.
- Research Institute for Medical Innovation, Radboudumc, Nijmegen, Netherlands.
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7
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Park J, Sturm M, Seibel-Kelemen O, Ossowski S, Haack TB. Lessons Learned from Translating Genome Sequencing to Clinical Routine: Understanding the Accuracy of a Diagnostic Pipeline. Genes (Basel) 2024; 15:136. [PMID: 38275617 PMCID: PMC10815474 DOI: 10.3390/genes15010136] [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: 12/20/2023] [Revised: 01/15/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024] Open
Abstract
The potential of genome sequencing (GS), which allows detection of almost all types of genetic variation across nearly the entire genome of an individual, greatly expands the possibility for diagnosing genetic disorders. The opportunities provided with this single test are enticing to researchers and clinicians worldwide for human genetic research as well as clinical application. Multiple studies have highlighted the advantages of GS for genetic variant discovery, emphasizing its added value for routine clinical use. We have implemented GS as first-line genetic testing for patients with rare diseases. Here, we report on our experiences in establishing GS as a reliable diagnostic method for almost all types of genetic disorders, from validating diagnostic accuracy of sequencing pipelines to clinical implementation in routine practice.
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Affiliation(s)
- Joohyun Park
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tübingen, Germany; (J.P.); (O.S.-K.); (S.O.)
| | - Marc Sturm
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tübingen, Germany; (J.P.); (O.S.-K.); (S.O.)
| | - Olga Seibel-Kelemen
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tübingen, Germany; (J.P.); (O.S.-K.); (S.O.)
| | - Stephan Ossowski
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tübingen, Germany; (J.P.); (O.S.-K.); (S.O.)
| | - Tobias B. Haack
- Institute of Medical Genetics and Applied Genomics, University of Tübingen, 72076 Tübingen, Germany; (J.P.); (O.S.-K.); (S.O.)
- Center for Rare Diseases, University of Tübingen, 72076 Tübingen, Germany
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8
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Barbitoff YA, Ushakov MO, Lazareva TE, Nasykhova YA, Glotov AS, Predeus AV. Bioinformatics of germline variant discovery for rare disease diagnostics: current approaches and remaining challenges. Brief Bioinform 2024; 25:bbad508. [PMID: 38271481 PMCID: PMC10810331 DOI: 10.1093/bib/bbad508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 11/18/2023] [Accepted: 12/12/2023] [Indexed: 01/27/2024] Open
Abstract
Next-generation sequencing (NGS) has revolutionized the field of rare disease diagnostics. Whole exome and whole genome sequencing are now routinely used for diagnostic purposes; however, the overall diagnosis rate remains lower than expected. In this work, we review current approaches used for calling and interpretation of germline genetic variants in the human genome, and discuss the most important challenges that persist in the bioinformatic analysis of NGS data in medical genetics. We describe and attempt to quantitatively assess the remaining problems, such as the quality of the reference genome sequence, reproducible coverage biases, or variant calling accuracy in complex regions of the genome. We also discuss the prospects of switching to the complete human genome assembly or the human pan-genome and important caveats associated with such a switch. We touch on arguably the hardest problem of NGS data analysis for medical genomics, namely, the annotation of genetic variants and their subsequent interpretation. We highlight the most challenging aspects of annotation and prioritization of both coding and non-coding variants. Finally, we demonstrate the persistent prevalence of pathogenic variants in the coding genome, and outline research directions that may enhance the efficiency of NGS-based disease diagnostics.
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Affiliation(s)
- Yury A Barbitoff
- Dpt. of Genomic Medicine, D.O. Ott Research Institute of Obstetrics, Gynaecology, and Reproductology, Mendeleevskaya line 3, 199034, St. Petersburg, Russia
- Bioinformatics Institute, Kentemirovskaya st. 2A, 197342, St. Petersburg, Russia
| | - Mikhail O Ushakov
- Dpt. of Genomic Medicine, D.O. Ott Research Institute of Obstetrics, Gynaecology, and Reproductology, Mendeleevskaya line 3, 199034, St. Petersburg, Russia
| | - Tatyana E Lazareva
- Dpt. of Genomic Medicine, D.O. Ott Research Institute of Obstetrics, Gynaecology, and Reproductology, Mendeleevskaya line 3, 199034, St. Petersburg, Russia
| | - Yulia A Nasykhova
- Dpt. of Genomic Medicine, D.O. Ott Research Institute of Obstetrics, Gynaecology, and Reproductology, Mendeleevskaya line 3, 199034, St. Petersburg, Russia
| | - Andrey S Glotov
- Dpt. of Genomic Medicine, D.O. Ott Research Institute of Obstetrics, Gynaecology, and Reproductology, Mendeleevskaya line 3, 199034, St. Petersburg, Russia
| | - Alexander V Predeus
- Bioinformatics Institute, Kentemirovskaya st. 2A, 197342, St. Petersburg, Russia
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9
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Al Eissa MM, Alotibi RS, Alhaddad B, Aloraini T, Samman MS, AlAsiri A, Abouelhoda M, AlQahtani AS. Reclassifying variations of unknown significance in diseases affecting Saudi Arabia's population reveal new associations. Front Genet 2023; 14:1250317. [PMID: 38028588 PMCID: PMC10646566 DOI: 10.3389/fgene.2023.1250317] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Accepted: 10/16/2023] [Indexed: 12/01/2023] Open
Abstract
Introduction: Physicians face diagnostic dilemmas upon reports indicating disease variants of unknown significance (VUS). The most puzzling cases are patients with rare diseases, where finding another matched genotype and phenotype to associate their results is challenging. This study aims to prove the value of updating patient files with new classifications, potentially leading to better assessment and prevention. Methodology: We recruited retrospective phenotypic and genotypic data from King Saud Medical City, Riyadh, Kingdom of Saudi Arabia. Between September 2020 and December 2021, 1,080 patients' genetic profiles were tested in a College of American Pathologists accredited laboratory. We excluded all confirmed pathogenic variants, likely pathogenic variants and copy number variations. Finally, we further reclassified 194 VUS using different local and global databases, employing in silico prediction to justify the phenotype-genotype association. Results: Of the 194 VUS, 90 remained VUS, and the other 104 were reclassified as follows: 16 pathogenic, 49 likely pathogenic, nine benign, and 30 likely benign. Moreover, most of these variants had never been observed in other local or international databases. Conclusion: Reclassifying the VUS adds value to understanding the causality of the phenotype if it has been reported in another family or population. The healthcare system should establish guidelines for re-evaluating VUS, and upgrading VUS should reflect on individual/family risks and management strategies.
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Affiliation(s)
- Mariam M. Al Eissa
- Public Health Authority, Public Health Lab, Molecular Genetics Laboratory, Riyadh, Saudi Arabia
- Medical School, AlFaisal University, Riyadh, Saudi Arabia
| | - Raniah S. Alotibi
- Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud bin Abdulaziz University for Health Sciences (KSAU-HS), Riyadh, Saudi Arabia
- King Abdullah International Medical Research Center (KAIMRC), Riyadh, Saudi Arabia
| | - Bader Alhaddad
- Laboratory Medicine Department, King Fahd University Hospital, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
- Molecular Genetics Department, King Saud Medical City, Riyadh, Saudi Arabia
| | - Taghrid Aloraini
- Division of Translational Pathology, Department of Laboratory Medicine, King Abdulaziz Medical City, Riyadh, Saudi Arabia
- Department of Genetics, King Abdullah Specialized Children Hospital, King Abdulaziz Medical City, MNGHA, Riyadh, Saudi Arabia
| | - Manar S. Samman
- Department of Pathology and Clinical Laboratory Medicine Administration, King Fahad Medical City (KFMC), Riyadh, Saudi Arabia
| | - Abdulrahman AlAsiri
- Medical Genomics Research Department, King Abdullah International Medical Research Center, King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
- Department of Cardiology, Division of Heart and Lungs, University Medical Center Utrecht, University of Utrecht, Utrecht, Netherlands
| | - Mohamed Abouelhoda
- Chairman Computational Science Department at King Faisal Specialised Hospital and Research Center, KFSHRC, Riyadh, Saudi Arabia
| | - Amerh S. AlQahtani
- Medical Genetics Department, King Saud Medical City, Riyadh, Saudi Arabia
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10
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Lee M, Lui ACY, Chan JCK, Doong PHL, Kwong AKY, Mak CCY, Li RHW, Kan ASY, Chung BHY. Revealing parental mosaicism: the hidden answer to the recurrence of apparent de novo variants. Hum Genomics 2023; 17:91. [PMID: 37798624 PMCID: PMC10557286 DOI: 10.1186/s40246-023-00535-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 09/18/2023] [Indexed: 10/07/2023] Open
Abstract
Mosaicism refers to the presence of two or more populations of genetically distinct cells within an individual, all of which originate from a single zygote. Previous literature estimated the percentage of parental mosaicism ranged from 0.33 to 25.9%. In this study, parents whose children had previously been diagnosed with developmental disorders with an apparent de novo variant were recruited. Peripheral blood, buccal and semen samples were collected from these parents if available for the detection of potential parental mosaicism using droplet digital PCR, complemented with the method of blocker displacement amplification. Among the 20 families being analyzed, we report four families with parental mosaicism (4/20, 20%). Two families have maternal gonosomal mosaicism (EYA1 and EBF3) and one family has paternal gonadal mosaicism (CHD7) with a pathogenic/ likely pathogenic variant. One family has a paternal gonosomal mosaicism with a variant of uncertain significance (FLNC) with high clinical relevance. The detectable variant allele frequency in our cohort ranged from 8.7-35.9%, limit of detection 0.08-0.16% based on our in-house EBF3 assay. Detecting parental mosaicism not only informs family with a more accurate recurrence risk, but also facilitates medical teams to create appropriate plans for pregnancy and delivery, offering the most suitable care.
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Affiliation(s)
- Mianne Lee
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, The University of Hong Kong, Room 115, 1/F, New Clinical Building, Pok Fu Lam, Hong Kong SAR, China
| | - Adrian C Y Lui
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, The University of Hong Kong, Room 115, 1/F, New Clinical Building, Pok Fu Lam, Hong Kong SAR, China
| | - Joshua C K Chan
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, The University of Hong Kong, Room 115, 1/F, New Clinical Building, Pok Fu Lam, Hong Kong SAR, China
| | - Phoenix H L Doong
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, The University of Hong Kong, Room 115, 1/F, New Clinical Building, Pok Fu Lam, Hong Kong SAR, China
| | - Anna K Y Kwong
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, The University of Hong Kong, Room 115, 1/F, New Clinical Building, Pok Fu Lam, Hong Kong SAR, China
| | - Christopher C Y Mak
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, The University of Hong Kong, Room 115, 1/F, New Clinical Building, Pok Fu Lam, Hong Kong SAR, China
| | - Raymond H W Li
- Department of Obstetrics and Gynaecology, Queen Mary Hospital, Pok Fu Lam, Hong Kong SAR, China
- Department of Obstetrics and Gynaecology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
| | - Anita S Y Kan
- Department of Obstetrics and Gynaecology, Queen Mary Hospital, Pok Fu Lam, Hong Kong SAR, China
- Department of Obstetrics and Gynaecology, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pok Fu Lam, Hong Kong SAR, China
- Prenatal Diagnostic Laboratory, Department of Obstetrics and Gynaecology, Tsan Yuk Hospital, Sai Wan Ho, Hong Kong SAR, China
| | - Brian H Y Chung
- Department of Paediatrics and Adolescent Medicine, School of Clinical Medicine, Li Ka Shing Faculty of Medicine, Queen Mary Hospital, The University of Hong Kong, Room 115, 1/F, New Clinical Building, Pok Fu Lam, Hong Kong SAR, China.
- Department of Paediatrics and Adolescent Medicine, Hong Kong Children's Hospital, Ngau Tau Kok, Hong Kong SAR, China.
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11
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Dzinovic I, Graf E, Brugger M, Berutti R, Příhodová I, Blaschek A, Winkelmann J, Jech R, Vill K, Zech M. Challenges in Establishing the Diagnosis of PRRT2-Related Dystonia: Recurrent Pathogenic Variants in a Homopolymeric Stretch. Mov Disord Clin Pract 2023; 10:1159-1161. [PMID: 37476319 PMCID: PMC10354604 DOI: 10.1002/mdc3.13793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 03/07/2023] [Accepted: 05/05/2023] [Indexed: 07/22/2023] Open
Affiliation(s)
- Ivana Dzinovic
- Institute of Neurogenomics, Helmholtz Zentrum MünchenMunichGermany
- Institute of Human Genetics, School of MedicineTechnical University of MunichMunichGermany
| | - Elisabeth Graf
- Institute of Human Genetics, School of MedicineTechnical University of MunichMunichGermany
| | - Melanie Brugger
- Institute of Human Genetics, School of MedicineTechnical University of MunichMunichGermany
| | - Riccardo Berutti
- Institute of Neurogenomics, Helmholtz Zentrum MünchenMunichGermany
- Institute of Human Genetics, School of MedicineTechnical University of MunichMunichGermany
| | - Iva Příhodová
- Department of NeurologyCharles University, 1st Faculty of Medicine and General University Hospital in PraguePragueCzech Republic
| | - Astrid Blaschek
- Dr. v. Hauner Children's Hospital, Department of Pediatric Neurology and Developmental MedicineLudwig‐Maximilians‐UniversitätMunichGermany
| | - Juliane Winkelmann
- Institute of Neurogenomics, Helmholtz Zentrum MünchenMunichGermany
- Institute of Human Genetics, School of MedicineTechnical University of MunichMunichGermany
- Lehrstuhl für Neurogenetik, Technische Universität MünchenMunichGermany
- Munich Cluster for Systems Neurology, SyNergyMunichGermany
| | - Robert Jech
- Department of NeurologyCharles University, 1st Faculty of Medicine and General University Hospital in PraguePragueCzech Republic
| | - Katharina Vill
- Dr. v. Hauner Children's Hospital, Department of Pediatric Neurology and Developmental MedicineLudwig‐Maximilians‐UniversitätMunichGermany
| | - Michael Zech
- Institute of Neurogenomics, Helmholtz Zentrum MünchenMunichGermany
- Institute of Human Genetics, School of MedicineTechnical University of MunichMunichGermany
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12
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Reiley J, Botas P, Miller CE, Zhao J, Malone Jenkins S, Best H, Grubb PH, Mao R, Isla J, Brunelli L. Open-Source Artificial Intelligence System Supports Diagnosis of Mendelian Diseases in Acutely Ill Infants. CHILDREN (BASEL, SWITZERLAND) 2023; 10:991. [PMID: 37371223 PMCID: PMC10296792 DOI: 10.3390/children10060991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 05/18/2023] [Accepted: 05/30/2023] [Indexed: 06/29/2023]
Abstract
Mendelian disorders are prevalent in neonatal and pediatric intensive care units and are a leading cause of morbidity and mortality in these settings. Current diagnostic pipelines that integrate phenotypic and genotypic data are expert-dependent and time-intensive. Artificial intelligence (AI) tools may help address these challenges. Dx29 is an open-source AI tool designed for use by clinicians. It analyzes the patient's phenotype and genotype to generate a ranked differential diagnosis. We used Dx29 to retrospectively analyze 25 acutely ill infants who had been diagnosed with a Mendelian disorder, using a targeted panel of ~5000 genes. For each case, a trio (proband and both parents) file containing gene variant information was analyzed, alongside patient phenotype, which was provided to Dx29 by three approaches: (1) AI extraction from medical records, (2) AI extraction with manual review/editing, and (3) manual entry. We then identified the rank of the correct diagnosis in Dx29's differential diagnosis. With these three approaches, Dx29 ranked the correct diagnosis in the top 10 in 92-96% of cases. These results suggest that non-expert use of Dx29's automated phenotyping and subsequent data analysis may compare favorably to standard workflows utilized by bioinformatics experts to analyze genomic data and diagnose Mendelian diseases.
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Affiliation(s)
- Joseph Reiley
- Division of Neonatology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
| | - Pablo Botas
- Foundation Twenty-Nine, 28223 Madrid, Spain
- Nostos Genomics, 10625 Berlin, Germany
| | - Christine E. Miller
- ARUP Laboratories, University of Utah Health Sciences Center, Salt Lake City, UT 84108, USA
- Valley Children’s Healthcare, Madera, CA 93636, USA
| | - Jian Zhao
- ARUP Laboratories, University of Utah Health Sciences Center, Salt Lake City, UT 84108, USA
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Sabrina Malone Jenkins
- Division of Neonatology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
| | - Hunter Best
- ARUP Laboratories, University of Utah Health Sciences Center, Salt Lake City, UT 84108, USA
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | - Peter H. Grubb
- Division of Neonatology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
| | - Rong Mao
- ARUP Laboratories, University of Utah Health Sciences Center, Salt Lake City, UT 84108, USA
- Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84132, USA
| | | | - Luca Brunelli
- Division of Neonatology, Department of Pediatrics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA
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13
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Yaldiz B, Kucuk E, Hampstead J, Hofste T, Pfundt R, Corominas Galbany J, Rinne T, Yntema HG, Hoischen A, Nelen M, Gilissen C. Twist exome capture allows for lower average sequence coverage in clinical exome sequencing. Hum Genomics 2023; 17:39. [PMID: 37138343 PMCID: PMC10155375 DOI: 10.1186/s40246-023-00485-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Accepted: 04/20/2023] [Indexed: 05/05/2023] Open
Abstract
BACKGROUND Exome and genome sequencing are the predominant techniques in the diagnosis and research of genetic disorders. Sufficient, uniform and reproducible/consistent sequence coverage is a main determinant for the sensitivity to detect single-nucleotide (SNVs) and copy number variants (CNVs). Here we compared the ability to obtain comprehensive exome coverage for recent exome capture kits and genome sequencing techniques. RESULTS We compared three different widely used enrichment kits (Agilent SureSelect Human All Exon V5, Agilent SureSelect Human All Exon V7 and Twist Bioscience) as well as short-read and long-read WGS. We show that the Twist exome capture significantly improves complete coverage and coverage uniformity across coding regions compared to other exome capture kits. Twist performance is comparable to that of both short- and long-read whole genome sequencing. Additionally, we show that even at a reduced average coverage of 70× there is only minimal loss in sensitivity for SNV and CNV detection. CONCLUSION We conclude that exome sequencing with Twist represents a significant improvement and could be performed at lower sequence coverage compared to other exome capture techniques.
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Affiliation(s)
- Burcu Yaldiz
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Erdi Kucuk
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Juliet Hampstead
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Tom Hofste
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Rolph Pfundt
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Jordi Corominas Galbany
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Tuula Rinne
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Helger G Yntema
- Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Alexander Hoischen
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Marcel Nelen
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Christian Gilissen
- Department of Human Genetics, Radboud Institute for Molecular Life Sciences, Radboud University Medical Centre, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.
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14
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Carter MT, Srour M, Au PYB, Buhas D, Dyack S, Eaton A, Inbar-Feigenberg M, Howley H, Kawamura A, Lewis SME, McCready E, Nelson TN, Vallance H. Genetic and metabolic investigations for neurodevelopmental disorders: position statement of the Canadian College of Medical Geneticists (CCMG). J Med Genet 2023; 60:523-532. [PMID: 36822643 DOI: 10.1136/jmg-2022-108962] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2022] [Accepted: 01/27/2023] [Indexed: 02/25/2023]
Abstract
PURPOSE AND SCOPE The aim of this position statement is to provide recommendations for clinicians regarding the use of genetic and metabolic investigations for patients with neurodevelopmental disorders (NDDs), specifically, patients with global developmental delay (GDD), intellectual disability (ID) and/or autism spectrum disorder (ASD). This document also provides guidance for primary care and non-genetics specialists caring for these patients while awaiting consultation with a clinical geneticist or metabolic specialist. METHODS OF STATEMENT DEVELOPMENT A multidisciplinary group reviewed existing literature and guidelines on the use of genetic and metabolic investigations for the diagnosis of NDDs and synthesised the evidence to make recommendations relevant to the Canadian context. The statement was circulated for comment to the Canadian College of Medical Geneticists (CCMG) membership-at-large and to the Canadian Pediatric Society (Mental Health and Developmental Disabilities Committee); following incorporation of feedback, it was approved by the CCMG Board of Directors on 1 September 2022. RESULTS AND CONCLUSIONS Chromosomal microarray is recommended as a first-tier test for patients with GDD, ID or ASD. Fragile X testing should also be done as a first-tier test when there are suggestive clinical features or family history. Metabolic investigations should be done if there are clinical features suggestive of an inherited metabolic disease, while the patient awaits consultation with a metabolic physician. Exome sequencing or a comprehensive gene panel is recommended as a second-tier test for patients with GDD or ID. Genetic testing is not recommended for patients with NDDs in the absence of GDD, ID or ASD, unless accompanied by clinical features suggestive of a syndromic aetiology or inherited metabolic disease.
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Affiliation(s)
| | - Myriam Srour
- Division of Neurology, McGill University Health Centre, Montreal, Québec, Canada
- Department of Pediatrics, McGill University, Montréal, QC, Canada
| | - Ping-Yee Billie Au
- Department of Medical Genetics, Alberta Children's Hospital, Calgary, Alberta, Canada
| | - Daniela Buhas
- Division of Medical Genetics, Department of Specialized Medicine, McGill University Health Centre, McGill University, Montreal, Québec, Canada
- Department of Human Genetics, McGill University, Montreal, QC, Canada
| | - Sarah Dyack
- Division of Medical Genetics, IWK Health Centre, Halifax, Nova Scotia, Canada
- Department of Pediatrics, Dalhousie University, Halifax, NS, Canada
| | - Alison Eaton
- Department of Medical Genetics, Stollery Children's Hospital, Edmonton, Alberta, Canada
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
| | - Michal Inbar-Feigenberg
- Division of Clinical and Metabolic Genetics, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Heather Howley
- Office of Research Services, CHEO Research Institute, Ottawa, Ontario, Canada
| | - Anne Kawamura
- Division of Developmental Pediatrics, Holland Bloorview Kids Rehabilitation Hospital, Toronto, Ontario, Canada
- Department of Paediatrics, University of Toronto, Toronto, ON, Canada
- Mental Health and Developmental Disability Committee, Canadian Pediatric Society, Ottawa, ON, Canada
- Canadian Paediatric Society, Toronto, Ontario, Canada
| | - Suzanne M E Lewis
- Department of Medical Genetics, BC Children's and Women's Hospital, Vancouver, British Columbia, Canada
| | - Elizabeth McCready
- Department of Pathology and Molecular Medicine, McMaster University, McMaster University, Hamilton, ON, Canada, Hamilton, Ontario, Canada
- Hamilton Regional Laboratory Medicine Program, Hamilton Health Sciences Centre, Hamilton, ON, Canada
| | - Tanya N Nelson
- Department of Pathology and Laboratory Medicine, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
| | - Hilary Vallance
- Department of Pathology and Laboratory Medicine, BC Children's Hospital, University of British Columbia, Vancouver, British Columbia, Canada
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15
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Evaluation of Individuals with Non-Syndromic Global Developmental Delay and Intellectual Disability. CHILDREN 2023; 10:children10030414. [PMID: 36979972 PMCID: PMC10047567 DOI: 10.3390/children10030414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/11/2023] [Accepted: 02/16/2023] [Indexed: 02/24/2023]
Abstract
Global Developmental Delay (GDD) and Intellectual Disability (ID) are two of the most common presentations encountered by physicians taking care of children. GDD/ID is classified into non-syndromic GDD/ID, where GDD/ID is the sole evident clinical feature, or syndromic GDD/ID, where there are additional clinical features or co-morbidities present. Careful evaluation of children with GDD and ID, starting with detailed history followed by a thorough examination, remain the cornerstone for etiologic diagnosis. However, when initial history and examination fail to identify a probable underlying etiology, further genetic testing is warranted. In recent years, genetic testing has been shown to be the single most important diagnostic modality for clinicians evaluating children with non-syndromic GDD/ID. In this review, we discuss different genetic testing currently available, review common underlying copy-number variants and molecular pathways, explore the recent evidence and recommendations for genetic evaluation and discuss an approach to the diagnosis and management of children with non-syndromic GDD and ID.
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16
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Five years' experience of the clinical exome sequencing in a Spanish single center. Sci Rep 2022; 12:19209. [PMID: 36357507 PMCID: PMC9649665 DOI: 10.1038/s41598-022-23786-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Accepted: 11/04/2022] [Indexed: 11/12/2022] Open
Abstract
Nowadays, exome sequencing is a robust and cost-efficient genetic diagnostic tool already implemented in many clinical laboratories. Despite it has undoubtedly improved our diagnostic capacity and has allowed the discovery of many new Mendelian-disease genes, it only provides a molecular diagnosis in up to 25-30% of cases. Here, we comprehensively evaluate the results of a large sample set of 4974 clinical exomes performed in our laboratory over a period of 5 years, showing a global diagnostic rate of 24.62% (1391/4974). For the evaluation we establish different groups of diseases and demonstrate how the diagnostic rate is not only dependent on the analyzed group of diseases (43.12% in ophthalmological cases vs 16.61% in neurological cases) but on the specific disorder (47.49% in retinal dystrophies vs 24.02% in optic atrophy; 18.88% in neuropathies/paraparesias vs 11.43% in dementias). We also detail the most frequent mutated genes within each group of disorders and discuss, on our experience, further investigations and directions needed for the benefit of patients.
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17
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The diagnostic yield, candidate genes, and pitfalls for a genetic study of intellectual disability in 118 middle eastern families. Sci Rep 2022; 12:18862. [PMID: 36344539 PMCID: PMC9640568 DOI: 10.1038/s41598-022-22036-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 10/07/2022] [Indexed: 11/09/2022] Open
Abstract
Global Developmental Delay/Intellectual disability (ID) is the term used to describe various disorders caused by abnormal brain development and characterized by impairments in cognition, communication, behavior, or motor skills. In the past few years, whole-exome sequencing (WES) has been proven to be a powerful, robust, and scalable approach for candidate gene discoveries in consanguineous populations. In this study, we recruited 215 patients affected with ID from 118 Middle Eastern families. Whole-exome sequencing was completed for 188 individuals. The average age at which WES was completed was 8.5 years. Pathogenic or likely pathogenic variants were detected in 32/118 families (27%). Variants of uncertain significance were seen in 33/118 families (28%). The candidate genes with a possible association with ID were detected in 32/118 (27%) with a total number of 64 affected individuals. These genes are novel, were previously reported in a single family, or cause strikingly different phenotypes with a different mode of inheritance. These genes included: AATK, AP1G2, CAMSAP1, CCDC9B, CNTROB, DNAH14, DNAJB4, DRG1, DTNBP1, EDRF1, EEF1D, EXOC8, EXOSC4, FARSB, FBXO22, FILIP1, INPP4A, P2RX7, PRDM13, PTRHD1, SCN10A, SCYL2, SMG8, SUPV3L1, TACC2, THUMPD1, XPR1, ZFYVE28. During the 5 years of the study and through gene matching databases, several of these genes have now been confirmed as causative of ID. In conclusion, understanding the causes of ID will help understand biological mechanisms, provide precise counseling for affected families, and aid in primary prevention.
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18
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Nagtzaam IF, van Leersum FS, Kouwenberg LC, Blok MJ, Vreeburg M, Steijlen PM, Gostyński A, van Geel M. STS pathogenic variants in a Dutch patient cohort clinically suspected for X-linked ichthyosis show genetic heterogeneity. Br J Dermatol 2022; 187:820-822. [PMID: 35822528 PMCID: PMC9804759 DOI: 10.1111/bjd.21775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 07/04/2022] [Accepted: 07/09/2022] [Indexed: 01/09/2023]
Abstract
Abstract
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Affiliation(s)
- Ivo F. Nagtzaam
- Department of Dermatology,GROW‐School for Oncology and ReproductionMaastricht UniversityMaastrichtthe Netherlands
| | - Frank S. van Leersum
- Department of Dermatology,GROW‐School for Oncology and ReproductionMaastricht UniversityMaastrichtthe Netherlands
| | - Laurie C.M. Kouwenberg
- Department of Dermatology,GROW‐School for Oncology and ReproductionMaastricht UniversityMaastrichtthe Netherlands
| | - Marinus J. Blok
- GROW‐School for Oncology and ReproductionMaastricht UniversityMaastrichtthe Netherlands,Department of Clinical GeneticsMaastricht University Medical Centre+Maastrichtthe Netherlands
| | - Maaike Vreeburg
- Department of Clinical GeneticsMaastricht University Medical Centre+Maastrichtthe Netherlands
| | - Peter M. Steijlen
- Department of Dermatology,GROW‐School for Oncology and ReproductionMaastricht UniversityMaastrichtthe Netherlands
| | - Antoni Gostyński
- Department of Dermatology,GROW‐School for Oncology and ReproductionMaastricht UniversityMaastrichtthe Netherlands
| | - Michel van Geel
- Department of Dermatology,GROW‐School for Oncology and ReproductionMaastricht UniversityMaastrichtthe Netherlands,Department of Clinical GeneticsMaastricht University Medical Centre+Maastrichtthe Netherlands
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19
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Husereau D, Steuten L, Muthu V, Thomas DM, Spinner DS, Ivany C, Mengel M, Sheffield B, Yip S, Jacobs P, Sullivan T. Effective and Efficient Delivery of Genome-Based Testing-What Conditions Are Necessary for Health System Readiness? Healthcare (Basel) 2022; 10:healthcare10102086. [PMID: 36292532 PMCID: PMC9602865 DOI: 10.3390/healthcare10102086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 10/09/2022] [Accepted: 10/12/2022] [Indexed: 01/09/2023] Open
Abstract
Health systems internationally must prepare for a future of genetic/genomic testing to inform healthcare decision-making while creating research opportunities. High functioning testing services will require additional considerations and health system conditions beyond traditional diagnostic testing. Based on a literature review of good practices, key informant interviews, and expert discussion, this article attempts to synthesize what conditions are necessary, and what good practice may look like. It is intended to aid policymakers and others designing future systems of genome-based care and care prevention. These conditions include creating communities of practice and healthcare system networks; resource planning; across-region informatics; having a clear entry/exit point for innovation; evaluative function(s); concentrated or coordinated service models; mechanisms for awareness and care navigation; integrating innovation and healthcare delivery functions; and revisiting approaches to financing, education and training, regulation, and data privacy and security. The list of conditions we propose was developed with an emphasis on describing conditions that would be applicable to any healthcare system, regardless of capacity, organizational structure, financing, population characteristics, standardization of care processes, or underlying culture.
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Affiliation(s)
- Don Husereau
- School of Epidemiology and Public Health, University of Ottawa, Ottawa, ON K1G 5Z3, Canada
- Correspondence: ; Tel.: +1-6132994379
| | - Lotte Steuten
- Office of Health Economics, London SE1 2HB, UK
- City Health Economics Centre (CHEC), City University of London, London EC1V 0HB, UK
| | - Vivek Muthu
- Marivek Healthcare Consulting, Epsom KT18 7PF, UK
| | - David M. Thomas
- Garvan Institute of Medical Research, Sydney, NSW 2010, Australia
- Omico, Sydney, NSW 2010, Australia
| | - Daryl S. Spinner
- Menarini Silicon Biosystems Inc., Huntingdon Valley, PA 19006, USA
| | - Craig Ivany
- Provincial Health Services Authority, Vancouver, BC V5Z 1G1, Canada
| | - Michael Mengel
- Department of Laboratory Medicine & Pathology, University of Alberta, Edmonton, AB T6G 2S2, Canada
| | | | - Stephen Yip
- Department of Pathology and Laboratory Medicine, Faculty of Medicine, University of British Columbia, Vancouver, BC V6T 1Z7, Canada
| | - Philip Jacobs
- Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Terrence Sullivan
- Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON M5T 3M6, Canada
- Gerald Bronfman Department of Oncology, McGill University, Montreal, QC H4A 3T2, Canada
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