1
|
Wu Y, Bayrak CS, Dong B, He S, Stenson PD, Cooper DN, Itan Y, Chen L. Identifying shared genetic factors underlying epilepsy and congenital heart disease in Europeans. Hum Genet 2023; 142:275-288. [PMID: 36352240 DOI: 10.1007/s00439-022-02502-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 10/24/2022] [Indexed: 11/11/2022]
Abstract
Epilepsy (EP) and congenital heart disease (CHD) are two apparently unrelated diseases that nevertheless display substantial mutual comorbidity. Thus, while congenital heart defects are associated with an elevated risk of developing epilepsy, the incidence of epilepsy in CHD patients correlates with CHD severity. Although genetic determinants have been postulated to underlie the comorbidity of EP and CHD, the precise genetic etiology is unknown. We performed variant and gene association analyses on EP and CHD patients separately, using whole exomes of genetically identified Europeans from the UK Biobank and Mount Sinai BioMe Biobank. We prioritized biologically plausible candidate genes and investigated the enriched pathways and other identified comorbidities by biological proximity calculation, pathway analyses, and gene-level phenome-wide association studies. Our variant- and gene-level results point to the Voltage-Gated Calcium Channels (VGCC) pathway as being a unifying framework for EP and CHD comorbidity. Additionally, pathway-level analyses indicated that the functions of disease-associated genes partially overlap between the two disease entities. Finally, phenome-wide association analyses of prioritized candidate genes revealed that cerebral blood flow and ulcerative colitis constitute the two main traits associated with both EP and CHD.
Collapse
Affiliation(s)
- Yiming Wu
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Cigdem Sevim Bayrak
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Bosi Dong
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Shixu He
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, People's Republic of China
| | - Peter D Stenson
- Institute of Medical Genetics, Cardiff University, Cardiff, UK
| | - David N Cooper
- Institute of Medical Genetics, Cardiff University, Cardiff, UK
| | - Yuval Itan
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA. .,Icahn School of Medicine at Mount Sinai, The Charles Bronfman Institute for Personalized Medicine, New York, NY, USA.
| | - Lei Chen
- Department of Neurology, West China Hospital of Sichuan University, Chengdu, Sichuan, People's Republic of China.
| |
Collapse
|
2
|
Sheidley BR, Malinowski J, Bergner AL, Bier L, Gloss DS, Mu W, Mulhern MM, Partack EJ, Poduri A. Genetic testing for the epilepsies: A systematic review. Epilepsia 2021; 63:375-387. [PMID: 34893972 DOI: 10.1111/epi.17141] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 11/22/2021] [Accepted: 11/23/2021] [Indexed: 12/29/2022]
Abstract
OBJECTIVE Numerous genetic testing options for individuals with epilepsy have emerged over the past decade without clear guidelines regarding optimal testing strategies. We performed a systematic evidence review (SER) and conducted meta-analyses of the diagnostic yield of genetic tests commonly utilized for patients with epilepsy. We also assessed nonyield outcomes (NYOs) such as changes in treatment and/or management, prognostic information, recurrence risk determination, and genetic counseling. METHODS We performed an SER, in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), using PubMed, Embase, CINAHL, and Cochrane Central through December of 2020. We included studies that utilized genome sequencing (GS), exome sequencing (ES), multigene panel (MGP), and/or genome-wide comparative genomic hybridization/chromosomal microarray (CGH/CMA) in cohorts (n ≥ 10) ascertained for epilepsy. Quality assessment was undertaken using ROBINS-I (Risk of Bias in Non-Randomized Studies of Interventions). We estimated diagnostic yields and 95% confidence intervals with random effects meta-analyses and narratively synthesized NYOs. RESULTS From 5985 nonduplicated articles published through 2020, 154 met inclusion criteria and were included in meta-analyses of diagnostic yield; 43 of those were included in the NYO synthesis. The overall diagnostic yield across all test modalities was 17%, with the highest yield for GS (48%), followed by ES (24%), MGP (19%), and CGH/CMA (9%). The only phenotypic factors that were significantly associated with increased yield were (1) the presence of developmental and epileptic encephalopathy and/or (2) the presence of neurodevelopmental comorbidities. Studies reporting NYOs addressed clinical and personal utility of testing. SIGNIFICANCE This comprehensive SER, focused specifically on the literature regarding patients with epilepsy, provides a comparative assessment of the yield of clinically available tests, which will help shape clinician decision-making and policy regarding insurance coverage for genetic testing. We highlight the need for prospective assessment of the clinical and personal utility of genetic testing for patients with epilepsy and for standardization in reporting patient characteristics.
Collapse
Affiliation(s)
- Beth R Sheidley
- Epilepsy Genetics Program, Division of Epilepsy and Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, Massachusetts, USA
| | | | - Amanda L Bergner
- Department of Genetics and Development, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Louise Bier
- Institute for Genomic Medicine, Columbia University Irving Medical Center, New York, New York, USA
| | - David S Gloss
- Department of Neurology, Charleston Area Medical Center, Charleston, West Virginia, USA
| | - Weiyi Mu
- Department of Genetic Medicine, Johns Hopkins University, Baltimore, Maryland, USA
| | - Maureen M Mulhern
- Department of Pathology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA.,Department of Neurology, Vagelos College of Physicians and Surgeons, Columbia University, New York, New York, USA
| | - Emily J Partack
- Genomics Services, Quest Diagnostics, Marlborough, Massachusetts, USA
| | - Annapurna Poduri
- Epilepsy Genetics Program, Division of Epilepsy and Neurophysiology, Department of Neurology, Boston Children's Hospital, Boston, Massachusetts, USA.,Department of Neurology, Harvard Medical School, Boston, Massachusetts, USA
| |
Collapse
|
3
|
Palka Bayard de Volo C, Alfonsi M, Morizio E, Guaciali-Franchi P, Mohn A, Chiarelli F. A 343 Italian cohort of patients analysed with array-comparative genomic hybridization: unsolved problems and genetic counselling difficulties. JOURNAL OF INTELLECTUAL DISABILITY RESEARCH : JIDR 2021; 65:863-869. [PMID: 34338393 DOI: 10.1111/jir.12867] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 06/11/2021] [Accepted: 06/27/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND The recent introduction of microarrays for genetic analyses has allowed higher etiological diagnostic rates in patient with intellectual disability (ID), autism spectrum disorders (ASD), epilepsy and multiple congenital anomalies (MCA), because of its resolution. This approach still results of high complexity and some limitations have been reported. In fact, it discloses several variants of unknown significance (VOUS) or incidental findings. In all cases, a massive amount of data is generated, because of this, the analysis and the interpretation is very difficult and often without a definitive conclusion. METHOD We analysed an Italian cohort of 343 patients with ID, MCA and ASD by array-comparative genomic hybridization. The purpose of this work was to consider the proportion of the chromosomal abnormalities in such cohort and to assess the distribution of the different type of the chromosomal abnormalities concerning their pathogenic significance, their origin and their correlation to these clinical phenotypes. RESULTS Array-comparative genomic hybridization analysis revealed 76 positive results. Abnormalities were detected in 27.8% of patients with ID, 11.1% with ASD, 10.7% with epilepsy and 19.4% with multiple congenital anomalies. The anomalies were classified in three major groups: group 1 (27 patients) with pathogenic alterations (P group); group 2 (34 patients) with VOUS potentially pathogenic (PP group); and group 3 (13 patients) with VOUS potentially benign (PB group). As expected, comparing the diagnostic groups, we observed a greater number of deletions in the P group and that all the abnormalities of the PB group were inherited. CONCLUSIONS Our retrospective study resulted in confirming the high detection rate of microarrays. CNV classification remains a complex procedure. The difficulty in CNV classification points out the importance of the patient selection, helping the interpretation of the molecular cytogenetic results.
Collapse
Affiliation(s)
| | - M Alfonsi
- Medical Genetics Unit, Ss Annunziata Hospital, Chieti, Italy
| | - E Morizio
- Department of Medical Genetics, G. d'Annunzio University, Chieti, Italy
| | - P Guaciali-Franchi
- Medical Genetics Unit, Ss Annunziata Hospital, Chieti, Italy
- Department of Medical Genetics, G. d'Annunzio University, Chieti, Italy
| | - A Mohn
- Department of Pediatrics, G. d'Annunzio University, Chieti, Italy
| | - F Chiarelli
- Department of Pediatrics, G. d'Annunzio University, Chieti, Italy
| |
Collapse
|
4
|
Cosemans N, Vandenhove L, Vogels A, Devriendt K, Van Esch H, Van Buggenhout G, Olivié H, de Ravel T, Ortibus E, Legius E, Aerssens P, Breckpot J, R Vermeesch J, Shen S, Fitzgerald J, Gallagher L, Peeters H. The clinical relevance of intragenic NRXN1 deletions. J Med Genet 2020; 57:347-355. [PMID: 31932357 DOI: 10.1136/jmedgenet-2019-106448] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 11/02/2019] [Accepted: 11/17/2019] [Indexed: 11/03/2022]
Abstract
BACKGROUND Intragenic NRXN1 deletions are susceptibility variants for neurodevelopmental disorders; however, their clinical interpretation is often unclear. Therefore, a literature study and an analysis of 43 previously unpublished deletions are provided. METHODS The literature cohort covered 629 heterozygous NRXN1 deletions: 148 in controls, 341 in probands and 140 in carrier relatives, and was used for clinical hypothesis testing. Exact breakpoint determination was performed for 43 in-house deletions. RESULTS The prevalence of exonic NRXN1 deletions in controls was ~1/3000 as compared with ~1/800 in patients with neurodevelopmental/neuropsychiatric disorders. The differential distribution of deletions across the gene between controls and probands allowed to distinguish distinct areas within the gene. Exon 6-24 deletions appeared only twice in over 100000 control individuals, had an estimated penetrance for neurodevelopmental disorders of 32.43%, a de novo rate of 50% and segregated mainly with intellectual disability (ID) and schizophrenia. In contrast, exon 1-5 deletions appeared in 20 control individuals, had an estimated penetrance of 12.59%, a de novo rate of 32.5% and were reported with a broad range of neurodevelopmental phenotypes. Exact breakpoint determination revealed six recurrent intron 5 deletions. CONCLUSION Exon 6-24 deletions have a high penetrance and are mainly associated with ID and schizophrenia. In contrast, the actual contribution of exon 1-5 deletions to a neurodevelopmental/neuropsychiatric disorder in an individual patient and family remains very difficult to assess. To enhance the clinical interpretation, this study provides practical considerations for counselling and an interactive table for comparing a deletion of interest with the available literature data.
Collapse
Affiliation(s)
- Nele Cosemans
- Department of Human Genetics, KU Leuven, Leuven, Belgium.,Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| | | | - Annick Vogels
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | | | - Hilde Van Esch
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | | | - Hilde Olivié
- Center for Developmental Disabilities Leuven, Leuven, Belgium
| | - Thomy de Ravel
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Els Ortibus
- Center for Developmental Disabilities Leuven, Leuven, Belgium.,Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Eric Legius
- Department of Human Genetics, KU Leuven, Leuven, Belgium.,Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| | | | | | | | - Sanbing Shen
- Regenerative Medicine Institute, School of Medicine, BioMedical Sciences Building, National University of Ireland (NUI), Galway, Ireland
| | | | - Louise Gallagher
- Trinity College Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland
| | - Hilde Peeters
- Department of Human Genetics, KU Leuven, Leuven, Belgium .,Leuven Autism Research (LAuRes), KU Leuven, Leuven, Belgium
| |
Collapse
|
5
|
Misra S, Peters G, Barnes E, Ardern-Holmes S, Webster R, Troedson C, Mohammad SS, Gill D, Menezes M, Gupta S, Procopis P, Antony J, Kurian MA, Dale RC. Yield of comparative genomic hybridization microarray in pediatric neurology practice. NEUROLOGY-GENETICS 2019; 5:e367. [PMID: 31872051 PMCID: PMC6878849 DOI: 10.1212/nxg.0000000000000367] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 08/28/2019] [Indexed: 12/14/2022]
Abstract
Objective The present study investigated the diagnostic yield of array comparative genomic hybridization (aCGH) in a large cohort of children with diverse neurologic disorders as seen in child neurology practice to test whether pathogenic copy number variants (CNVs) were more likely to be detected in specific neurologic phenotypes. Methods A retrospective cross-sectional analysis was performed on 555 children in whom a genetic etiology was suspected and who underwent whole-genome aCGH testing between 2006 and 2012. Neurologic phenotyping was performed using hospital medical records. An assessment of pathogenicity was made for each CNV, based on recent developments in the literature. Results Forty-seven patients were found to carry a pathogenic CNV, giving an overall diagnostic yield of 8.59%. Certain phenotypes predicted for the presence of a pathogenic CNV, including developmental delay (odds ratio [OR] 3.69 [1.30-10.51]), cortical visual impairment (OR 2.73 [1.18-6.28]), dysmorphism (OR 2.75 [1.38-5.50]), and microcephaly (OR 2.16 [1.01-4.61]). The combination of developmental delay/intellectual disability with dysmorphism and abnormal head circumference was also predictive for a pathogenic CNV (OR 2.86 [1.02-8.00]). For every additional clinical feature, there was an increased likelihood of detecting a pathogenic CNV (OR 1.18 [1.01-1.38]). Conclusions The use of aCGH led to a pathogenic finding in 8.59% of patients. The results support the use of aCGH as a first tier investigation in children with diverse neurologic disorders, although whole-genome sequencing may replace aCGH as the detection method in the future. In particular, the yield was increased in children with developmental delay, dysmorphism, cortical visual impairment, and microcephaly.
Collapse
Affiliation(s)
- Shibalik Misra
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Greg Peters
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Elizabeth Barnes
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Simone Ardern-Holmes
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Richard Webster
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Christopher Troedson
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Shekeeb S Mohammad
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Deepak Gill
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Manoj Menezes
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Sachin Gupta
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Peter Procopis
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Jayne Antony
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Manju A Kurian
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| | - Russell C Dale
- Kids Neuroscience Centre (S.M., R.D.), the Children's Hospital at Westmead, Faculty of Medicine and Health, the University of Sydney; Department of Clinical Genetics (G.P.) at the Children's Hospital at Westmead; Kids Research Institute at Westmead (E.B.); TY Nelson Department of Neurology and Neurosurgery at the Children's Hospital at Westmead Sydney (S.A.-H., R.W., C.T., S.S.M., D.G., M.M., S.G., P.P., J.A., R.C.D.), New South Wales, Australia; and Institute of Child Health (M.K.), University College London, UK
| |
Collapse
|
6
|
Castronovo P, Baccarin M, Ricciardello A, Picinelli C, Tomaiuolo P, Cucinotta F, Frittoli M, Lintas C, Sacco R, Persico AM. Phenotypic spectrum of NRXN1 mono- and bi-allelic deficiency: A systematic review. Clin Genet 2019; 97:125-137. [PMID: 30873608 DOI: 10.1111/cge.13537] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Revised: 03/01/2019] [Accepted: 03/10/2019] [Indexed: 01/13/2023]
Abstract
Neurexins are presynaptic cell adhesion molecules critically involved in synaptogenesis and vesicular neurotransmitter release. They are encoded by three genes (NRXN1-3), each yielding a longer alpha (α) and a shorter beta (β) transcript. Deletions spanning the promoter and the initial exons of the NRXN1 gene, located in chromosome 2p16.3, are associated with a variety of neurodevelopmental, psychiatric, neurological and neuropsychological phenotypes. We have performed a systematic review to define (a) the clinical phenotypes most associated with mono-allelic exonic NRXN1 deletions, and (b) the phenotypic features of NRXN1 bi-allelic deficiency due to compound heterozygous deletions/mutations. Clinically, three major conclusions can be drawn: (a) incomplete penetrance and pleiotropy do not allow reliable predictions of clinical outcome following prenatal detection of mono-allelic exonic NRXN1 deletions. Newborn carriers should undergo periodic neuro-behavioral observations for the timely detection of warning signs and the prescription of early behavioral intervention; (b) the presence of additional independent genetic risk factors should always be sought, as they may influence prognosis; (c) children with exonic NRXN1 deletions displaying early-onset, severe psychomotor delay in the context of a Pitt-Hopkins-like syndrome 2 phenotype, should undergo DNA sequencing of the spared NRXN1 allele in search for mutations or very small insertions/deletions.
Collapse
Affiliation(s)
- Paola Castronovo
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Marco Baccarin
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Arianna Ricciardello
- Interdepartmental Program "Autism 0-90", "Gaetano Martino" University Hospital, University of Messina, Messina, Italy
| | - Chiara Picinelli
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Pasquale Tomaiuolo
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Francesca Cucinotta
- Interdepartmental Program "Autism 0-90", "Gaetano Martino" University Hospital, University of Messina, Messina, Italy
| | - Myriam Frittoli
- Laboratory for Pervasive Developmental Disorders, Mafalda Luce Center, Milan, Italy
| | - Carla Lintas
- Service for Neurodevelopmental Disorders & Laboratory of Molecular Psychiatry and Neurogenetics, University "Campus Bio-Medico", Rome, Italy
| | - Roberto Sacco
- Service for Neurodevelopmental Disorders & Laboratory of Molecular Psychiatry and Neurogenetics, University "Campus Bio-Medico", Rome, Italy
| | - Antonio M Persico
- Interdepartmental Program "Autism 0-90", "Gaetano Martino" University Hospital, University of Messina, Messina, Italy
| |
Collapse
|
7
|
Tsuchida N, Nakashima M, Kato M, Heyman E, Inui T, Haginoya K, Watanabe S, Chiyonobu T, Morimoto M, Ohta M, Kumakura A, Kubota M, Kumagai Y, Hamano SI, Lourenco CM, Yahaya NA, Ch'ng GS, Ngu LH, Fattal-Valevski A, Weisz Hubshman M, Orenstein N, Marom D, Cohen L, Goldberg-Stern H, Uchiyama Y, Imagawa E, Mizuguchi T, Takata A, Miyake N, Nakajima H, Saitsu H, Miyatake S, Matsumoto N. Detection of copy number variations in epilepsy using exome data. Clin Genet 2018; 93:577-587. [PMID: 28940419 DOI: 10.1111/cge.13144] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Revised: 09/12/2017] [Accepted: 09/17/2017] [Indexed: 12/14/2022]
Abstract
Epilepsies are common neurological disorders and genetic factors contribute to their pathogenesis. Copy number variations (CNVs) are increasingly recognized as an important etiology of many human diseases including epilepsy. Whole-exome sequencing (WES) is becoming a standard tool for detecting pathogenic mutations and has recently been applied to detecting CNVs. Here, we analyzed 294 families with epilepsy using WES, and focused on 168 families with no causative single nucleotide variants in known epilepsy-associated genes to further validate CNVs using 2 different CNV detection tools using WES data. We confirmed 18 pathogenic CNVs, and 2 deletions and 2 duplications at chr15q11.2 of clinically unknown significance. Of note, we were able to identify small CNVs less than 10 kb in size, which might be difficult to detect by conventional microarray. We revealed 2 cases with pathogenic CNVs that one of the 2 CNV detection tools failed to find, suggesting that using different CNV tools is recommended to increase diagnostic yield. Considering a relatively high discovery rate of CNVs (18 out of 168 families, 10.7%) and successful detection of CNV with <10 kb in size, CNV detection by WES may be able to surrogate, or at least complement, conventional microarray analysis.
Collapse
Affiliation(s)
- N Tsuchida
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan.,Department of Stem Cell and Immune Regulation, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - M Nakashima
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan.,Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - M Kato
- Department of Pediatrics, Yamagata University Faculty of Medicine, Yamagata, Japan.,Department of Pediatrics, Showa University School of Medicine, Tokyo, Japan
| | - E Heyman
- Pediatric Neurology Department Pediatric Epilepsy Service, Assaf Harofeh Medical Center, Zerifin, Israel
| | - T Inui
- Department of Neurology, Miyagi Children's Hospital, Sendai, Japan
| | - K Haginoya
- Department of Neurology, Miyagi Children's Hospital, Sendai, Japan
| | - S Watanabe
- Department of Neurology, Miyagi Children's Hospital, Sendai, Japan
| | - T Chiyonobu
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - M Morimoto
- Department of Pediatrics, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - M Ohta
- Department of Pediatrics, JA Toride General Hospital, Toride, Ibaraki, Japan
| | - A Kumakura
- Department of Pediatrics, Kitano Hospital, The Tazuke Kofukai Medical Research Institute, Osaka, Japan
| | - M Kubota
- Division of Neurology, National Center for Child Health and Development, Tokyo, Japan
| | - Y Kumagai
- Division of Neurology, Saitama Children's Medical Center, Saitama, Japan
| | - S-I Hamano
- Division of Neurology, Saitama Children's Medical Center, Saitama, Japan
| | - C M Lourenco
- Neurogenetics Unit, School of Medicine of Ribeirao Preto, University of Sao Paulo, Sao Paulo, Brazil
| | - N A Yahaya
- Hospital Raja Perempuan Zainab II, Kota Bharu, Malaysia
| | - G-S Ch'ng
- Genetic Department, Hospital Kuala Lumpur, Kuala Lumpur, Malaysia
| | - L-H Ngu
- Genetic Department, Hospital Kuala Lumpur, Kuala Lumpur, Malaysia
| | - A Fattal-Valevski
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Pediatric Neurology Unit, Dana-Dwek Children's Hospital, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
| | - M Weisz Hubshman
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Pediatric Genetics Unit, Schneider Children's Medical Center of Israel, Petach Tikva, Israel.,Raphael Recanati Genetics Institute, Rabin Medical Center, Petach Tikva, Israel
| | - N Orenstein
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Pediatric Genetics Unit, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - D Marom
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Pediatric Genetics Unit, Schneider Children's Medical Center of Israel, Petach Tikva, Israel.,Pediatrics A, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - L Cohen
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.,Pediatric Genetics Unit, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - H Goldberg-Stern
- Epilepsy Unit, Schneider Children's Medical Center of Israel, Petach Tikva, Israel
| | - Y Uchiyama
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - E Imagawa
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - T Mizuguchi
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - A Takata
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - N Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - H Nakajima
- Department of Stem Cell and Immune Regulation, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| | - H Saitsu
- Department of Biochemistry, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - S Miyatake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan.,Clinical Genetics Department, Yokohama City University Hospital, Yokohama, Japan
| | - N Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, Yokohama, Japan
| |
Collapse
|
8
|
Chrna7 deficient mice manifest no consistent neuropsychiatric and behavioral phenotypes. Sci Rep 2017; 7:39941. [PMID: 28045139 PMCID: PMC5206704 DOI: 10.1038/srep39941] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 11/28/2016] [Indexed: 11/22/2022] Open
Abstract
The alpha7 nicotinic acetylcholine receptor, encoded by the CHRNA7 gene, has been implicated in various psychiatric and behavioral disorders, including schizophrenia, bipolar disorder, epilepsy, autism, Alzheimer’s disease, and Parkinson’s disease, and is considered a potential target for therapeutic intervention. 15q13.3 microdeletion syndrome is a rare genetic disorder, caused by submicroscopic deletions on chromosome 15q. CHRNA7 is the only gene in this locus that has been deleted entirely in cases involving the smallest microdeletions. Affected individuals manifest variable neurological and behavioral phenotypes, which commonly include developmental delay/intellectual disability, epilepsy, and autism spectrum disorder. Subsets of patients have short attention spans, aggressive behaviors, mood disorders, or schizophrenia. Previous behavioral studies suggested that Chrna7 deficient mice had attention deficits, but were normal in baseline behavioral responses, learning, memory, and sensorimotor gating. Given a growing interest in CHRNA7-related diseases and a better appreciation of its associated human phenotypes, an in-depth behavioral characterization of the Chrna7 deficient mouse model appeared prudent. This study was designed to investigate whether Chrna7 deficient mice manifest phenotypes related to those seen in human individuals, using an array of 12 behavioral assessments and electroencephalogram (EEG) recordings on freely-moving mice. Examined phenotypes included social interaction, compulsive behaviors, aggression, hyperactivity, anxiety, depression, and somatosensory gating. Our data suggests that mouse behavior and EEG recordings are not sensitive to decreased Chrna7 copy number.
Collapse
|
9
|
Patel J, Mercimek-Mahmutoglu S. Epileptic Encephalopathy in Childhood: A Stepwise Approach for Identification of Underlying Genetic Causes. Indian J Pediatr 2016; 83:1164-74. [PMID: 26821542 DOI: 10.1007/s12098-015-1979-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2015] [Accepted: 12/02/2015] [Indexed: 01/29/2023]
Abstract
Epilepsy is one of the most common neurological disorders in childhood. Epilepsy associated with global developmental delay and cognitive dysfunction is defined as epileptic encephalopathy. Certain inherited metabolic disorders presenting with epileptic encephalopathy can be treated with disease specific diet, vitamin, amino acid or cofactor supplementations. In those disorders, disease specific therapy is successful to achieve good seizure control and improve long-term neurodevelopmental outcome. For this reason, intractable epilepsy with global developmental delay or history of developmental regression warrants detailed metabolic investigations for the possibility of an underlying treatable inherited metabolic disorder, which should be undertaken as first line investigations. An underlying genetic etiology in epileptic encephalopathy has been supported by recent studies such as array comparative genomic hybridization, targeted next generation sequencing panels, whole exome and whole genome sequencing. These studies report a diagnostic yield up to 70%, depending on the applied genetic testing as well as number of patients enrolled. In patients with epileptic encephalopathy, a stepwise approach for diagnostic work-up will help to diagnose treatable inherited metabolic disorders quickly. Application of detailed genetic investigations such as targeted next generation sequencing as second line and whole exome sequencing as third line testing will diagnose underlying genetic disease which will help for genetic counseling as well as guide for prenatal diagnosis. Knowledge of underlying genetic cause will provide novel insights into the pathogenesis of epileptic encephalopathy and pave the ground towards the development of targeted neuroprotective treatment strategies to improve the health outcome of children with epileptic encephalopathy.
Collapse
Affiliation(s)
- Jaina Patel
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada
| | - Saadet Mercimek-Mahmutoglu
- Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, 555 University Avenue, Toronto, Ontario, M5G 1X8, Canada. .,Genetics and Genome Biology Program, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada.
| |
Collapse
|
10
|
Yang L, Faraone SV, Zhang-James Y. Autism spectrum disorder traits in Slc9a9 knock-out mice. Am J Med Genet B Neuropsychiatr Genet 2016; 171B:363-76. [PMID: 26755066 DOI: 10.1002/ajmg.b.32415] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2014] [Accepted: 12/22/2015] [Indexed: 11/09/2022]
Abstract
Autism spectrum disorders (ASDs) are a group of neurodevelopmental disorders which begin in childhood and persist into adulthood. They cause lifelong impairments and are associated with substantial burdens to patients, families, and society. Genetic studies have implicated the sodium/proton exchanger (NHE) nine gene, Slc9a9, to ASDs and attention-deficit/hyperactivity disorder(ADHD). Slc9a9 encodes, NHE9, a membrane protein of the late recycling endosomes. The recycling endosome plays an important role in synapse development and plasticity by regulating the trafficking of membrane neurotransmitter receptors and transporters. Here we tested the hypothesis that Slc9a9 knock-out (KO) mice would show ADHD-like and ASD-like traits. Ultrasonic vocalization (USV) recording showed that Slc9a9 KO mice emitted fewer calls and had shorter call durations, which suggest communication impairment. Slc9a9 KO mice lacked a preference for social novelty, but did not show deficits in social approach; Slc9a9 KO mice spent more time self-grooming, an indicator for restricted and repetitive behavior. We did not observe hyperactivity or other behavior impairments which are commonly comorbid with ASDs in human, such as anxiety-like behavior. Our study is the first animal behavior study that links Slc9a9 to ASDs. By eliminatingNHE9 activity, it provides strong evidence that lack of Slc9a9leads to ASD-like behaviors in mice and provides the field with a new mouse model of ASDs.
Collapse
Affiliation(s)
- Lina Yang
- Departments of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, New York
| | - Stephen V Faraone
- Departments of Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, New York.,Departments of Psychiatry, SUNY Upstate Medical University, Syracuse, New York.,K.G. Jebsen Centre for Research on Neuropsychiatric Disorders, University of Bergen, Bergen, Norway
| | - Yanli Zhang-James
- Departments of Psychiatry, SUNY Upstate Medical University, Syracuse, New York
| |
Collapse
|
11
|
Gillentine MA, Schaaf CP. The human clinical phenotypes of altered CHRNA7 copy number. Biochem Pharmacol 2015; 97:352-362. [PMID: 26095975 DOI: 10.1016/j.bcp.2015.06.012] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 06/10/2015] [Indexed: 01/03/2023]
Abstract
Copy number variants (CNVs) have been implicated in multiple neuropsychiatric conditions, including autism spectrum disorder (ASD), schizophrenia, and intellectual disability (ID). Chromosome 15q13 is a hotspot for such CNVs due to the presence of low copy repeat (LCR) elements, which facilitate non-allelic homologous recombination (NAHR). Several of these CNVs have been overrepresented in individuals with neuropsychiatric disorders; yet variable expressivity and incomplete penetrance are commonly seen. Dosage sensitivity of the CHRNA7 gene, which encodes for the α7 nicotinic acetylcholine receptor in the human brain, has been proposed to have a major contribution to the observed cognitive and behavioral phenotypes, as it represents the smallest region of overlap to all the 15q13.3 deletions and duplications. Individuals with zero to four copies of CHRNA7 have been reported in the literature, and represent a range of clinical severity, with deletions causing generally more severe and more highly penetrant phenotypes. Potential mechanisms to account for the variable expressivity within each group of 15q13.3 CNVs will be discussed.
Collapse
Affiliation(s)
- Madelyn A Gillentine
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States
| | - Christian P Schaaf
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, United States; Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, United States.
| |
Collapse
|
12
|
Abstract
The aim of this study was to determine prospectively the frequency of pathogenic chromosomal microdeletions and microduplications in a large group of referred patients with developmental delay (DD), intellectual disability (ID) or autism spectrum disorders (ASD) within a genetic diagnostic service. First tier testing was applied using a standardised oligo-array comparative genomic hybridization (CGH) platform, replacing conventional cytogenetic testing that would have been used in the past. Copy number variants (CNVs) found to be responsible for the clinical condition on the request form could all be subdivided into three groups: well established pathogenic microdeletion/microduplication/aneuploidy syndromes, predicted pathogenic CNVs as interpreted by the laboratory, and recently established pathogenic disease susceptibility CNVs. Totalled from these three groups, with CNVs of uncertain significance excluded, detection rates were: DD (13.0%), ID (15.6%), ASD (2.3%), ASD with DD (8.2%), ASD with ID (12.7%) and unexplained epilepsy with DD, ID and ASD (10.9%). The greater diagnostic sensitivity arising from routine application of array CGH, compared with previously used conventional cytogenetics, outweighs the interpretative issues for the reporting laboratory and referring clinician arising from detection of CNVs of uncertain significance. Precise determination of any previously hidden molecular defect responsible for the patient's condition is translated to improved genetic counselling.
Collapse
|
13
|
Gai D, Haan E, Scholar M, Nicholl J, Yu S. Phenotypes of AKT3 deletion: a case report and literature review. Am J Med Genet A 2014; 167A:174-9. [PMID: 25424989 DOI: 10.1002/ajmg.a.36710] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2014] [Accepted: 06/27/2014] [Indexed: 11/08/2022]
Abstract
AKT3 (v-akt murine thymoma viral oncogene homolog 3) is located at chromosome 1q44 and encodes a 479 amino acid protein, a member of the protein kinase B (PKB) family. This gene is frequently involved in 1q44 deletion syndrome in patients with microcephaly, intellectual disability, and dysmorphic features. Phenotype and genotype studies of patients with 1q44 deletion syndrome have suggested that deletion of the AKT3 gene is responsible for the microcephaly in these patients. However, the phenotype of pure AKT3 deletion has not been studied. We report on a 1q44 deletion involving only AKT3 in a boy and his father. The boy has microcephaly, hypotonia, feeding difficulties, developmental delay, and minor dysmorphic features. His father does not have microcephaly and is of normal intelligence. We also analyzed the available information on the phenotypes of 13 individuals carrying a pure AKT3 gene deletion identified through literature review and database search. To our knowledge, this is the first report of a paternally inherited pure AKT3 deletion with full clinical description. This is also the first report to suggest that (1) AKT3 deletion is associated with microcephaly and intellectual disability with incomplete penetrance; (2) a pure AKT3 deletion is likely to be inherited in contrast to the larger 1q44 deletions, which are mostly de novo and (3) there seems to be no consistent or characteristic dysmorphism associated with pure AKT3 deletion.
Collapse
Affiliation(s)
- Dayu Gai
- Royal Melbourne Hospital, Parkville, Victoria, Australia
| | | | | | | | | |
Collapse
|
14
|
Kuroda Y, Ohashi I, Saito T, Nagai JI, Ida K, Naruto T, Iai M, Kurosawa K. Refinement of the deletion in 8q22.2-q22.3: The minimum deletion size at 8q22.3 related to intellectual disability and epilepsy. Am J Med Genet A 2014; 164A:2104-8. [DOI: 10.1002/ajmg.a.36604] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2013] [Accepted: 04/04/2014] [Indexed: 11/06/2022]
Affiliation(s)
- Yukiko Kuroda
- Division of Medical Genetics; Kanagawa Children's Medical Center; Yokohama Japan
| | - Ikuko Ohashi
- Division of Medical Genetics; Kanagawa Children's Medical Center; Yokohama Japan
| | - Toshiyuki Saito
- Department of Clinical Laboratory; Kanagawa Children's Medical Center; Yokohama Japan
| | - Jun-ichi Nagai
- Department of Clinical Laboratory; Kanagawa Children's Medical Center; Yokohama Japan
| | - Kazumi Ida
- Division of Medical Genetics; Kanagawa Children's Medical Center; Yokohama Japan
| | - Takuya Naruto
- Division of Medical Genetics; Kanagawa Children's Medical Center; Yokohama Japan
| | - Mizue Iai
- Division of Pediatric Neurology; Kanagawa Children's Medical Center; Yokohama Japan
| | - Kenji Kurosawa
- Division of Medical Genetics; Kanagawa Children's Medical Center; Yokohama Japan
| |
Collapse
|
15
|
Abstract
Hereditary neurological disorders (HNDs) are relatively common in children compared to those occurring in adulthood. Recognising clinical manifestations of HNDs is important for the selection of genetic testing, genetic testing results interpretation, and genetic consultation. Meanwhile, advances in next generation sequencing (NGS) technologies have significantly enabled the discovery of genetic causes of HNDs and also challenge paediatricians on applying genetic investigation. Combination of both clinical information and advanced technologies will enhance the genetic test yields in clinical setting. This review summarises the clinical presentations as well as genetic causes of paediatric neurological disorders in four major areas including movement disorders, neuropsychiatric disorders, neuron peripheral disorders and epilepsy. The aim of this review is to help paediatric neurologists not only to see the clinical features but also the complex genetic aspect of HNDs in order to utilise genetic investigation confidently in their clinical practice. A smooth transition from research based to clinical use of comprehensive genetic testing in HNDs in children could be foreseen in the near future while genetic testing, genetic counselling and genetic data interpretation are in place appropriately.
Collapse
Affiliation(s)
- Yue Huang
- 1 Neuroscience Research Australia & the University of New South Wales, NSW, 2031, Australia ; 2 Department of Genetic Medicine, SA Pathology at Women's and Children's Hospital, North Adelaide, School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, South Australia, Australia ; 3 Cytogenetics Department, Western Sydney Genetics Program, Children's Hospital at Westmead, NSW, 2145, Australia ; 4 Department of Neurology, Xiangya Hospital, Central South University & National Laboratory of Medical Genetics of China, Changsha 410000, China
| | - Sui Yu
- 1 Neuroscience Research Australia & the University of New South Wales, NSW, 2031, Australia ; 2 Department of Genetic Medicine, SA Pathology at Women's and Children's Hospital, North Adelaide, School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, South Australia, Australia ; 3 Cytogenetics Department, Western Sydney Genetics Program, Children's Hospital at Westmead, NSW, 2145, Australia ; 4 Department of Neurology, Xiangya Hospital, Central South University & National Laboratory of Medical Genetics of China, Changsha 410000, China
| | - Zhanhe Wu
- 1 Neuroscience Research Australia & the University of New South Wales, NSW, 2031, Australia ; 2 Department of Genetic Medicine, SA Pathology at Women's and Children's Hospital, North Adelaide, School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, South Australia, Australia ; 3 Cytogenetics Department, Western Sydney Genetics Program, Children's Hospital at Westmead, NSW, 2145, Australia ; 4 Department of Neurology, Xiangya Hospital, Central South University & National Laboratory of Medical Genetics of China, Changsha 410000, China
| | - Beisha Tang
- 1 Neuroscience Research Australia & the University of New South Wales, NSW, 2031, Australia ; 2 Department of Genetic Medicine, SA Pathology at Women's and Children's Hospital, North Adelaide, School of Paediatrics and Reproductive Health, The University of Adelaide, Adelaide, South Australia, Australia ; 3 Cytogenetics Department, Western Sydney Genetics Program, Children's Hospital at Westmead, NSW, 2145, Australia ; 4 Department of Neurology, Xiangya Hospital, Central South University & National Laboratory of Medical Genetics of China, Changsha 410000, China
| |
Collapse
|
16
|
Lacaze E, Gruchy N, Penniello-Valette MJ, Plessis G, Richard N, Decamp M, Mittre H, Leporrier N, Andrieux J, Kottler ML, Gerard M. De novo 15q13.3 microdeletion with cryptogenic West syndrome. Am J Med Genet A 2013; 161A:2582-7. [PMID: 23929658 DOI: 10.1002/ajmg.a.36085] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Accepted: 05/20/2013] [Indexed: 11/11/2022]
Abstract
West syndrome is a well-recognized form of epilepsy, defined by a triad of infantile spasms, hypsarrhythmia and developmental arrest. West syndrome is heterogenous, caused by mutations of genes ARX, STXBP1, KCNT1 among others; 16p13.11 and 17q21.31 microdeletions are less frequent, usually associated with intellectual disability and facial dysmorphism. So-called "idiopathic" West syndrome is of better prognostic, without prior intellectual deficiency and usually responsive to anti-epileptic treatment. We report on a boy falling within the scope of idiopathic West syndrome, with no dysmorphic features and normal development before the beginning of West syndrome, with a good resolution after treatment, bearing a de novo 15q13.3 microdeletion. Six genes are located in the deleted region, including CHRNA7, which encodes a subunit of a nicotinic acetylcholine receptor, and is frequently associated with epilepsy. Exploration of the 15q13.3 region should be proposed in idiopathic West syndrome.
Collapse
Affiliation(s)
- Elodie Lacaze
- Department of Genetics, Hôpital Côte de Nacre, Caen, France
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Béna F, Bruno DL, Eriksson M, van Ravenswaaij-Arts C, Stark Z, Dijkhuizen T, Gerkes E, Gimelli S, Ganesamoorthy D, Thuresson AC, Labalme A, Till M, Bilan F, Pasquier L, Kitzis A, Dubourgm C, Rossi M, Bottani A, Gagnebin M, Sanlaville D, Gilbert-Dussardier B, Guipponi M, van Haeringen A, Kriek M, Ruivenkamp C, Antonarakis SE, Anderlid BM, Slater HR, Schoumans J. Molecular and clinical characterization of 25 individuals with exonic deletions of NRXN1 and comprehensive review of the literature. Am J Med Genet B Neuropsychiatr Genet 2013; 162B:388-403. [PMID: 23533028 DOI: 10.1002/ajmg.b.32148] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2012] [Accepted: 02/22/2013] [Indexed: 11/12/2022]
Abstract
This study aimed to elucidate the observed variable phenotypic expressivity associated with NRXN1 (Neurexin 1) haploinsufficiency by analyses of the largest cohort of patients with NRXN1 exonic deletions described to date and by comprehensively reviewing all comparable copy number variants in all disease cohorts that have been published in the peer reviewed literature (30 separate papers in all). Assessment of the clinical details in 25 previously undescribed individuals with NRXN1 exonic deletions demonstrated recurrent phenotypic features consisting of moderate to severe intellectual disability (91%), severe language delay (81%), autism spectrum disorder (65%), seizures (43%), and hypotonia (38%). These showed considerable overlap with previously reported NRXN1-deletion associated phenotypes in terms of both spectrum and frequency. However, we did not find evidence for an association between deletions involving the β-isoform of neurexin-1 and increased head size, as was recently published in four cases with a deletion involving the C-terminus of NRXN1. We identified additional rare copy number variants in 20% of cases. This study supports a pathogenic role for heterozygous exonic deletions of NRXN1 in neurodevelopmental disorders. The additional rare copy number variants identified may act as possible phenotypic modifiers as suggested in a recent digenic model of neurodevelopmental disorders.
Collapse
Affiliation(s)
- Frédérique Béna
- Service of Genetic Medicine, Geneva University Hospital, Geneva, Switzerland
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|