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Matteoli G, Alvente S, Bastianini S, Berteotti C, Ciani E, Cinelli E, Lo Martire V, Medici G, Mello T, Miglioranza E, Silvani A, Mutolo D, Zoccoli G. Characterisation of sleep apneas and respiratory circuitry in mice lacking CDKL5. J Sleep Res 2024:e14295. [PMID: 39049436 DOI: 10.1111/jsr.14295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 07/09/2024] [Accepted: 07/11/2024] [Indexed: 07/27/2024]
Abstract
CDKL5 deficiency disorder is a rare genetic disease caused by mutations in the CDKL5 gene. Central apneas during wakefulness have been reported in patients with CDKL5 deficiency disorder. Studies on CDKL5-knockout mice, a CDKL5 deficiency disorder model, reported sleep apneas, but it is still unclear whether these events are central (central sleep apnea) or obstructive (obstructive sleep apnea) and may be related to alterations of brain circuits that modulate breathing rhythm. This study aimed to discriminate central sleep apnea and obstructive sleep apnea in CDKL5-knockout mice, and explore changes in the somatostatin neurons expressing high levels of neurokinin-1 receptors within the preBötzinger complex. Ten adult male wild-type and 12 CDKL5-knockout mice underwent electrode implantation for sleep stage discrimination and diaphragmatic activity recording, and were studied using whole-body plethysmography for 7 hr during the light (resting) period. Sleep apneas were categorised as central sleep apnea or obstructive sleep apnea based on the recorded signals. The number of somatostatin neurons in the preBötzinger complex and their neurokinin-1 receptors expression were assessed through immunohistochemistry in a sub-group of animals. CDKL5-knockout mice exhibited a higher apnea occurrence rate and a greater prevalence of obstructive sleep apnea during rapid eye movement sleep, compared with wild-type, whereas no significant difference was observed for central sleep apnea. Moreover, CDKL5-knockout mice showed a reduced number of somatostatin neurons in the preBötzinger complex, and these neurons expressed a lower level of neurokinin-1 receptors compared with wild-type controls. These findings underscore the pivotal role of CDKL5 in regulating normal breathing, suggesting its potential involvement in shaping preBötzinger complex neural circuitry and controlling respiratory muscles during sleep.
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Affiliation(s)
- Gabriele Matteoli
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Sara Alvente
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Stefano Bastianini
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Chiara Berteotti
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Elisabetta Ciani
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Elenia Cinelli
- Department of Experimental and Clinical Medicine, Section of Physiology, University of Florence, Florence, Italy
| | - Viviana Lo Martire
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Giorgio Medici
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Tommaso Mello
- Department of Experimental and Clinical Biochemical Sciences "Mario Serio", University of Florence, Florence, Italy
| | - Elena Miglioranza
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Alessandro Silvani
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
| | - Donatella Mutolo
- Department of Experimental and Clinical Medicine, Section of Physiology, University of Florence, Florence, Italy
| | - Giovanna Zoccoli
- Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum - University of Bologna, Bologna, Italy
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Lombardo A, Sinibaldi L, Genovese S, Catino G, Mei V, Pompili D, Sallicandro E, Falasca R, Liambo MT, Faggiano MV, Roberti MC, Di Donato M, Vitelli A, Russo S, Giannini R, Micalizzi A, Pietrafusa N, Digilio MC, Novelli A, Fusco L, Alesi V. A Case of CDKL5 Deficiency Due to an X Chromosome Pericentric Inversion: Delineation of Structural Rearrangements as an Overlooked Recurrent Pathological Mechanism. Int J Mol Sci 2024; 25:6912. [PMID: 39000022 PMCID: PMC11241409 DOI: 10.3390/ijms25136912] [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: 05/07/2024] [Revised: 06/11/2024] [Accepted: 06/13/2024] [Indexed: 07/14/2024] Open
Abstract
CDKL5 deficiency disorder (CDD) is an X-linked dominant epileptic encephalopathy, characterized by early-onset and drug-resistant seizures, psychomotor delay, and slight facial features. Genomic variants inactivating CDKL5 or impairing its protein product kinase activity have been reported, making next-generation sequencing (NGS) and chromosomal microarray analysis (CMA) the standard diagnostic tests. We report a suspicious case of CDD in a female child who tested negative upon NGS and CMA and harbored an X chromosome de novo pericentric inversion. The use of recently developed genomic techniques (optical genome mapping and whole-genome sequencing) allowed us to finely characterize the breakpoints, with one of them interrupting CDKL5 at intron 1. This is the fifth case of CDD reported in the scientific literature harboring a structural rearrangement on the X chromosome, providing evidence for the hypothesis that this type of anomaly can represent a recurrent pathogenic mechanism, whose frequency is likely underestimated, with it being overlooked by standard techniques. The identification of the molecular etiology of the disorder is extremely important in evaluating the pathological outcome and to better investigate the mechanisms associated with drug resistance, paving the way for the development of specific therapies. Karyotype and genomic techniques should be considered in all cases presenting with CDD without molecular confirmation.
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Affiliation(s)
- Antonietta Lombardo
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Lorenzo Sinibaldi
- Medical Genetics Unit, IRCCS Bambino Gesù Children Hospital, 00165 Rome, Italy
| | - Silvia Genovese
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Giorgia Catino
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Valerio Mei
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Daniele Pompili
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Ester Sallicandro
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Roberto Falasca
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Maria Teresa Liambo
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Maria Vittoria Faggiano
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Maria Cristina Roberti
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Maddalena Di Donato
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Anna Vitelli
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Serena Russo
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Rosalinda Giannini
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Alessia Micalizzi
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
- Medical Genetics Unit, San Pietro Fatebenefratelli Hospital, 00189 Rome, Italy
| | - Nicola Pietrafusa
- Neurology, Epilepsy and Movement Disorders Unit, Bambino Gesù, IRCCS Children's Hospital, 00165 Rome, Italy
| | | | - Antonio Novelli
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
| | - Lucia Fusco
- Neurology, Epilepsy and Movement Disorders Unit, Bambino Gesù, IRCCS Children's Hospital, 00165 Rome, Italy
| | - Viola Alesi
- Laboratory of Medical Genetics, Translational Cytogenomics Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00165 Rome, Italy
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Charfi Triki C, Zouari Mallouli S, Ben Jdila M, Ben Said M, Kamoun Feki F, Weckhuysen S, Masmoudi S, Fakhfakh F. First report of Tunisian patients with CDKL5-related encephalopathy. Epilepsia Open 2024; 9:906-917. [PMID: 37701975 PMCID: PMC11145601 DOI: 10.1002/epi4.12824] [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: 02/06/2023] [Accepted: 09/09/2023] [Indexed: 09/14/2023] Open
Abstract
OBJECTIVE Mutations in the cyclin-dependent kinase-like 5 gene (CDKL5) are associated with a wide spectrum of clinical presentations. Early-onset epileptic encephalopathy (EOEE) is the most recognized phenotype. Here we describe phenotypic features in eight Tunisian patients with CDKL5-related encephalopathy. METHODS We included all cases with clinical features consistent with CDKL5-related encephalopathy: infantile epileptic spasm, acquired microcephaly, movement disorders and visual impairment. We collected data about seizure types, electroencephalogram, magnetic resonance imaging, and metabolic analysis. The diagnosis of CDKL5 mutation was made thanks to Sanger sequencing with an ABI PRISM 3100-Avant automated DNA sequencer using a Big Dye Terminator Cycle Sequencing Reaction Kit v1.1. and Next Generation Sequencing (NGS) since the development of a gene panel responsible for DEE within the framework of "Strengthening the Sfax University Expertise for diagnosis and management of epileptic encephalopathies". RESULTS We collected four boys and four girls aged meanly 6 years old with confirmed mutation on CDKL5 gene. Overall, we identified five de novo CDKL5 mutations including three Frame-shift mutations, one missense mutation, and a splicing variant. The mean age at first seizure onset was 4 months. The first seizure type was infantile epileptic spasm (4/8) followed by tonic (2/8) and myoclonic seizures (2/8). Out of eight cases, four exhibited two stages epileptic course while epilepsy in three other patients progressed on three stages. Regarding development, most cases (6/8) had psychomotor retardation from the start whilst the two others showed psychomotor regression with the onset of seizures. Additional clinical features included visual impairment (7/8), tone abnormalities (7/8), stereotypies (7/8), and acquired microcephaly (6/8). SIGNIFICANCE Our present report delineates an unusual phenotype of CDKL5-related encephalopathy with male gender predominance and delayed onset epilepsy. It interestingly described new phenotypic features and uncommon benign developmental profiles in boys, different patterns of CDKL5-epilepsy, neuroimaging findings, and CDKL5 mutational spectrum.
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Affiliation(s)
- Chahnez Charfi Triki
- Child Neurology Department, Hedi Chaker Sfax University Hospital, and Research Laboratory LR19ES15University of SfaxSfaxTunisia
| | - Salma Zouari Mallouli
- Child Neurology Department, Hedi Chaker Sfax University Hospital, and Research Laboratory LR19ES15University of SfaxSfaxTunisia
| | - Marwa Ben Jdila
- Laboratory of Molecular and Functional Genetics, Faculty of Science of SfaxUniversity of SfaxSfaxTunisia
| | - Mariem Ben Said
- Laboratory of Molecular and Cellular Screening Processes (LPCMC), Center of Biotechnology of SfaxUniversity of SfaxSfaxTunisia
| | - Fatma Kamoun Feki
- Child Neurology Department, Hedi Chaker Sfax University Hospital, and Research Laboratory LR19ES15University of SfaxSfaxTunisia
| | - Sarah Weckhuysen
- Applied & Translational Neurogenomics Group, VIB Center for Molecular Neurology, VIBUniversity of AntwerpAntwerpBelgium
- Department of NeurologyAntwerp University HospitalAntwerpBelgium
- Translational Neurosciences, Faculty of Medicine and Health ScienceUniversity of AntwerpAntwerpBelgium
| | - Sabeur Masmoudi
- Laboratory of Molecular and Cellular Screening Processes (LPCMC), Center of Biotechnology of SfaxUniversity of SfaxSfaxTunisia
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Science of SfaxUniversity of SfaxSfaxTunisia
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Amin S, Møller RS, Aledo‐Serrano A, Arzimanoglou A, Bager P, Jóźwiak S, Kluger GJ, López‐Cabeza S, Nabbout R, Partridge C, Schubert‐Bast S, Specchio N, Kälviäinen R. Providing quality care for people with CDKL5 deficiency disorder: A European expert panel opinion on the patient journey. Epilepsia Open 2024; 9:832-849. [PMID: 38450883 PMCID: PMC11145618 DOI: 10.1002/epi4.12914] [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: 04/28/2023] [Accepted: 01/21/2024] [Indexed: 03/08/2024] Open
Abstract
Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a developmental and epileptic encephalopathy caused by variants in the CDKL5 gene. The disorder is characterized by intractable early-onset seizures, severe neurodevelopmental delay, hypotonia, motor disabilities, cerebral (cortical) visual impairment and microcephaly. With no disease-modifying therapies available for CDD, treatment is symptomatic with an initial focus on seizure control. Another unmet need in the management of people with CDD is the lack of evidence to aid standardized care and guideline development. To address this gap, experts in CDD and representatives from patient advocacy groups from Denmark, Finland, France, Germany, Italy, Poland, Spain, and the United Kingdom convened to form an Expert Working Group. The aim was to provide an expert opinion consensus on how to ensure quality care in routine clinical practice within the European setting, including in settings with limited experience or resources for multidisciplinary care of CDD and other developmental and epileptic encephalopathies. By means of one-to-one interviews around the current treatment landscape in CDD, insights from the Expert Working Group were collated and developed into a Europe-specific patient journey for individuals with CDD, which was later validated by the group. Further discussions followed to gain consensus of opinions on challenges and potential solutions for achieving quality care in this setting. The panel recognized the benefit of early genetic testing, a holistic personalized approach to seizure control (taking into consideration various factors such as concomitant medications and comorbidities), and age- and comorbidity-dependent multidisciplinary care for optimizing patient outcomes and quality of life. However, their insights and experiences also highlighted much disparity in management approaches and resources across different European countries. Development of standardized European recommendations is required to align realistic diagnostic criteria, treatment goals, and management approaches that can be adapted for different settings. PLAIN LANGUAGE SUMMARY: Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a rare condition caused by a genetic mutation with a broad range of symptoms apparent from early childhood, including epileptic seizures that do not respond to medication and severe delays in development. Due to the lack of guidance on managing CDD, international experts and patient advocates discussed best practices in the care of people with CDD in Europe. The panel agreed that early testing, a personalized approach to managing seizures, and access to care from different disciplines are beneficial. Development of guidelines to ensure that care is standardized would also be valuable.
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Affiliation(s)
- Sam Amin
- University Hospitals BristolBristolUK
| | - Rikke S. Møller
- The Danish Epilepsy Centre, FiladelfiaDianalundDenmark
- Department of Regional Health Research, Faculty of Health SciencesUniversity of Southern DenmarkOdenseDenmark
| | - Angel Aledo‐Serrano
- Vithas Madrid La Milagrosa University HospitalVithas Hospital GroupMadridSpain
| | | | | | | | - Gerhard Josef Kluger
- Epilepsy Center for Children and AdolescentsVogtareuthGermany
- Paracelsus Medical University SalzburgSalzburgAustria
| | | | - Rima Nabbout
- Necker‐Enfants Malades HospitalUniversité Paris Cité, Imagine InstituteParisFrance
| | | | - Susanne Schubert‐Bast
- Center of Neurology and NeurosurgeryEpilepsy Center Frankfurt Rhine‐MainGoethe‐University and University Hospital FrankfurtFrankfurt am MainGermany
- LOEWE Center for Personalized and Translational Epilepsy Research (CePTER)Goethe‐UniversityFrankfurt am MainGermany
- University Children's HospitalGoethe‐University and University Hospital FrankfurtFrankfurt am MainGermany
| | | | - Reetta Kälviäinen
- University of Eastern Finland and Epilepsy CenterKuopio University HospitalKuopioFinland
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Gras M, Heide S, Keren B, Valence S, Garel C, Whalen S, Jansen AC, Keymolen K, Stouffs K, Jennesson M, Poirsier C, Lesca G, Depienne C, Nava C, Rastetter A, Curie A, Cuisset L, Des Portes V, Milh M, Charles P, Mignot C, Héron D. Further characterisation of ARX-related disorders in females due to inherited or de novo variants. J Med Genet 2024; 61:103-108. [PMID: 37879892 DOI: 10.1136/jmg-2023-109203] [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: 02/09/2023] [Accepted: 09/30/2023] [Indexed: 10/27/2023]
Abstract
The Aristaless-related homeobox (ARX) gene is located on the X chromosome and encodes a transcription factor that is essential for brain development. While the clinical spectrum of ARX-related disorders is well described in males, from X linked lissencephaly with abnormal genitalia syndrome to syndromic and non-syndromic intellectual disability (ID), its phenotypic delineation in females is incomplete. Carrier females in ARX families are usually asymptomatic, but ID has been reported in some of them, as well as in others with de novo variants. In this study, we collected the clinical and molecular data of 10 unpublished female patients with de novo ARX pathogenic variants and reviewed the data of 63 females from the literature with either de novo variants (n=10), inherited variants (n=33) or variants of unknown inheritance (n=20). Altogether, the clinical spectrum of females with heterozygous pathogenic ARX variants is broad: 42.5% are asymptomatic, 16.4% have isolated agenesis of the corpus callosum (ACC) or mild symptoms (learning disabilities, autism spectrum disorder, drug-responsive epilepsy) without ID, whereas 41% present with a severe phenotype (ie, ID or developmental and epileptic encephalopathy (DEE)). The ID/DEE phenotype was significantly more prevalent in females carrying de novo variants (75%, n=15/20) versus in those carrying inherited variants (27.3%, n=9/33). ACC was observed in 66.7% (n=24/36) of females who underwent a brain MRI. By refining the clinical spectrum of females carrying ARX pathogenic variants, we show that ID is a frequent sign in females with this X linked condition.
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Affiliation(s)
- Mathilde Gras
- Department of Clinical Genetics, APHP Sorbonne Université, University Hospital Pitié Salpêtrière, Paris, France
| | - Solveig Heide
- Department of Clinical Genetics, APHP Sorbonne Université, University Hospital Pitié Salpêtrière, Paris, France
- Reference Center for Rare Diseases « Intellectual disabilities of rare causes » Déficiences Intellectuelles de Causes Rares, University Hospital Pitié Salpêtrière, Paris, France
- Doctoral College, Sorbonne University, Paris, France
| | - Boris Keren
- Department of Clinical Genetics, APHP Sorbonne Université, University Hospital Pitié Salpêtrière, Paris, France
| | - Stéphanie Valence
- Unit of Pediatric Neurology, APHP Sorbonne Université, Armand-Trousseau Hospital, Paris, France
- Reference Center for Rare Diseases « Intellectual disabilites of rare causes » Déficiences Intellectuelles de Causes Rares, Armand-Trousseau Hospital, Paris, France
| | - Catherine Garel
- Unit of Pediatric Radiology, APHP Sorbonne Université, Armand-Trousseau Hospital, Paris, France
| | - Sandra Whalen
- Department of Clinical Genetics and Reference Center for Rare Diseases « Developmental disorders and syndromes », APHP Sorbonne Université, Armand-Trousseau Hospital, Paris, France
| | - Anna C Jansen
- Neurogenetics Research Group, Vrije Universiteit Brussel, Brussels, Belgium
| | - Kathelijn Keymolen
- Clinical Sciences, Research Group Reproduction and Genetics, Centre for Medical Genetics, Universitair Ziekenhuis Brussel (UZ Brussels), Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Katrien Stouffs
- Clinical Sciences, Research Group Reproduction and Genetics, Centre for Medical Genetics, Universitair Ziekenhuis Brussel (UZ Brussels), Vrije Universiteit Brussel (VUB), Brussels, Belgium
| | - Mélanie Jennesson
- Pediatrics Unit, University Hospital of Reims, American Memorial Hospital, Reims, France
| | - Céline Poirsier
- UF génétique clinique, Pôle Femme-Parents-Enfants, CHU Reims, Reims, France
| | - Gaetan Lesca
- Department of Genetics, Referral Center for Developmental Anomalies and Malformative Syndromes, Centre-est HCL, Hospices Civils de Lyon, Lyon, France
| | - Christel Depienne
- Institute of Human Genetics, University Hospital Essen, University of Duisburg-Essen, Essen, Germany
| | | | | | - Aurore Curie
- Reference Centre for Rare Diseases « Intellectual disabilities of rare causes », Civil Hospices of Lyon, Lyon, France
- University Lyon 1 Faculty of Medicine Lyon-Est, Lyon, France
| | - Laurence Cuisset
- APHP Centre Université Paris Cité, Service de Médecine Génomique des Maladies de Système et d'Organe, Cochin Hospital, Paris, France
| | - Vincent Des Portes
- Reference Centre for Rare Diseases « Intellectual disabilities of rare causes », Civil Hospices of Lyon, Lyon, France
- University Lyon 1 Faculty of Medicine Lyon-Est, Lyon, France
| | - Mathieu Milh
- Department of Neurology Pediatrics, AP-HM, Hôpital de la Timone, Marseille, France
| | - Perrine Charles
- Department of Clinical Genetics, APHP Sorbonne Université, University Hospital Pitié Salpêtrière, Paris, France
- Reference Center for Rare Diseases « Intellectual disabilities of rare causes » Déficiences Intellectuelles de Causes Rares, University Hospital Pitié Salpêtrière, Paris, France
| | - Cyril Mignot
- Department of Clinical Genetics, APHP Sorbonne Université, University Hospital Pitié Salpêtrière, Paris, France
- Reference Center for Rare Diseases « Intellectual disabilities of rare causes » Déficiences Intellectuelles de Causes Rares, University Hospital Pitié Salpêtrière, Paris, France
| | - Delphine Héron
- Department of Clinical Genetics, APHP Sorbonne Université, University Hospital Pitié Salpêtrière, Paris, France
- Reference Center for Rare Diseases « Intellectual disabilities of rare causes » Déficiences Intellectuelles de Causes Rares, University Hospital Pitié Salpêtrière, Paris, France
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You Y, Men X, Wu W, Liu S, He X, Sun S, Wang X, Li B. Clinical and functional study of two de novo variations of CDKL5 gene. Neurogenetics 2023; 24:263-271. [PMID: 37584787 DOI: 10.1007/s10048-023-00731-x] [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: 03/30/2023] [Accepted: 08/09/2023] [Indexed: 08/17/2023]
Abstract
The cyclin-dependent kinase like 5 (CDKL5) gene variation is X-linked dominant and is associated with type 2 developmental and epileptic encephalopathy (DEE). Although numerous cases of CDKL5 have been reported, there is limited discussion regarding functional verification. We described two children with DEE caused by de novo variations of CDKL5 gene, analyzed their clinical manifestations, and performed genetic testing on their gene variation sites. The two cases presented with tonic seizures followed by epileptic spasms, indicative of refractory epilepsy. Physical examination revealed abnormal facial features, including wide eye distance, low nose base, and high nose bridge. Both cases exhibited developmental disabilities. Cranial magnetic resonance imaging (MRI) showed widening of the bilateral frontotemporal extracerebral space. Genetic testing identified variations at the gene sites c.463 + 4A > G (splicing) and c.1854_1861delCAAAGTGA (p.D618Efs*18). Minigene experiments further confirmed that the intronic variation c.463 + 4A > G (splicing) disrupted splicing, leading to protein truncation. CDKL5 gene variation can lead to DEE, and intron variation site c.463 + 4A > G (splicing) can cause protein truncation, which is a pathogenic variation.
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Affiliation(s)
- Yang You
- Department of Imaging, The Fourth Hospital of Hebei Medical University, Shijiazhuang, 050000, Hebei, China
| | - Xinyi Men
- Department of Pediatrics, The Second Hospital of Hebei Medical University, Shijiazhuang, 050000, Hebei, China
| | - Wenjuan Wu
- Department of Neurology, Hebei Children's Hospital, Hebei Children's Hospital Affiliated to Hebei Medical University, 133 Jianhua Nan Street, Shijiazhuang, 050031, Hebei, China
| | - Shan Liu
- Department of Neurology, Hebei Children's Hospital, Hebei Children's Hospital Affiliated to Hebei Medical University, 133 Jianhua Nan Street, Shijiazhuang, 050031, Hebei, China
| | - Xuexin He
- Department of Rehabilitation, Shijiazhuang Hospital of Traditional Chinese Medicine, 233 Zhongshan Road, Shijiazhuang, Hebei, 050000, China
| | - Suzhen Sun
- Department of Neurology, Hebei Children's Hospital, Hebei Children's Hospital Affiliated to Hebei Medical University, 133 Jianhua Nan Street, Shijiazhuang, 050031, Hebei, China
| | - Xiuxia Wang
- Department of Pediatrics, The Second Hospital of Hebei Medical University, Shijiazhuang, 050000, Hebei, China.
| | - Baoguang Li
- Department of Neurology, Hebei Children's Hospital, Hebei Children's Hospital Affiliated to Hebei Medical University, 133 Jianhua Nan Street, Shijiazhuang, 050031, Hebei, China.
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7
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Darra F, Monchelato M, Loos M, Juanes M, Bernardina BD, Valenzuela GR, Gallo A, Caraballo R. CDKL5-associated developmental and epileptic encephalopathy: A long-term, longitudinal electroclinical study of 22 cases. Epilepsy Res 2023; 190:107098. [PMID: 36739728 DOI: 10.1016/j.eplepsyres.2023.107098] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2022] [Revised: 01/02/2023] [Accepted: 01/23/2023] [Indexed: 01/26/2023]
Abstract
OBJECTIVE The study was conducted to analyze the possible diagnostic value of the electroclinical semiology of the epileptic seizures. METHODS We evaluated the medical records of 17 females and 5 males with CDKL5 deficiency disorder (CDD) considering the long-term evolution, including the polygraphic video-EEG recordings. RESULTS We recognized three disease phases. We found that the seizure semiology was already recognizable in the first phase of the syndrome. In the short-term evolution, all patients had focal motor and 12/21 hypermotor seizures. Both epileptic spasms and myoclonic seizures were already present in more than half of the cases in the first 2 months after onset. In the second phase, the intermediate period, the polymorphic pattern was maintained, but in eight patients the electroclinical pattern of epileptic encephalopathy with hypsarrhythmia appeared. In the long-term period, the seizure polymorphism continued but myoclonic and epileptic spasms diminished. Tonic seizures appeared in the last 2 phases. Progressively, with the aggravation of seizures and paroxysmal EEG abnormalities impairment of the neurocognitive status was observed. Severe behavioral disturbances were seen in eight and autistic-like features in 14. CONCLUSION CDD is a true developmental and epileptic encephalopathy with a specific etiology characterized by the early appearance of epileptic seizures that quickly become polymorphic and drug resistant in infants that are most often female and already have neurological impairment. Polygraphic video-EEG recordings are important to recognize ictal events of the association of hypermotor seizures, epileptic spasms in clusters, and massive myoclonic jerks, already present at onset.
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Affiliation(s)
- Francesca Darra
- Unit of Child Neuropsychiatry, Azienda Ospedaliera Universitaria Integrata, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - Manuela Monchelato
- Unit of Child Neuropsychiatry, Azienda Ospedaliera Universitaria Integrata, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - Mariana Loos
- Department of Neurology, Hospital de Padiatría J.P. Garrahan, Buenos Aires, Argentina
| | - Matias Juanes
- Genomics Laboratory, Hospital de Padiatría J.P. Garrahan, Buenos Aires, Argentina
| | - Bernardo Dalla Bernardina
- Unit of Child Neuropsychiatry, Azienda Ospedaliera Universitaria Integrata, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | | | - Adolfo Gallo
- Department of Neurology, Hospital de Padiatría J.P. Garrahan, Buenos Aires, Argentina
| | - Roberto Caraballo
- Department of Neurology, Hospital de Padiatría J.P. Garrahan, Buenos Aires, Argentina.
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8
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CDKL5 deficiency causes epileptic seizures independent of cellular mosaicism. J Neurol Sci 2022; 443:120498. [PMID: 36417806 DOI: 10.1016/j.jns.2022.120498] [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: 07/20/2022] [Revised: 10/06/2022] [Accepted: 11/12/2022] [Indexed: 11/17/2022]
Abstract
OBJECTIVE In a study using a mouse model of CDKL5 deficiency disorder (CDD), seizures are specific to female mice heterozygous for Cdkl5 mutations and not observed in hemizygous knockout males or homozygous knockout females. The aim of this study was to examine whether the clinical phenotype of patients with CDD can be impacted by the type of genetic variant. METHODS Eleven CDD patients (six females and five males) were included in this study. The molecular diagnosis of hemizygous male patients was performed using digital PCR and their clinical phenotypes were compared with those of patients with mosaic or heterozygous CDKL5 variants. The severity of clinical phenotypes was graded by using CDKL5 Developmental Score and the adapted version of the CDKL5 Clinical Severity Assessment. The effect of cellular mosaicism on the severity of CDD was studied by comparing the clinical characteristics and comorbidities between individuals with hemizygous and mosaic or heterozygous CDKL5 variants. RESULTS One of the five male patients was mosaic for the CDKL5 variant. All patients developed seizures irrespective of their genetic status of the pathogenic variant. However, cellular mosaicism of CDKL5 deficiency was associated with lesser severity of other comorbidities such as feeding, respiratory, and visual functional impairments. SIGNIFICANCE This study provided evidence that cellular mosaicism of CDKL5 deficiency was not necessarily required for developing epilepsy. CDD patients not only exhibited clinical features of epilepsy but also exhibited the developmental consequences arising directly from the effect of the CDKL5 pathogenic variant.
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9
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Rodak M, Jonderko M, Rozwadowska P, Machnikowska-Sokołowska M, Paprocka J. CDKL5 Deficiency Disorder (CDD)-Rare Presentation in Male. CHILDREN (BASEL, SWITZERLAND) 2022; 9:children9121806. [PMID: 36553250 PMCID: PMC9776588 DOI: 10.3390/children9121806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 11/07/2022] [Accepted: 11/18/2022] [Indexed: 11/25/2022]
Abstract
CDKL5 deficiency disorder (CDD) is a developmental encephalopathy caused by pathogenic variants in the X-linked cyclin-dependent kinase 5 (CDKL5) gene. This rare disorder occurs more frequently in females than in males. The incidence is estimated to be approximately 1: 40,000-60,000 live births. So far, 50 cases have been described in boys. The clinical course in males tends to be more severe and is often associated with death in the first or second decade of life. The authors present an unreported 2.5-year-old male patient with drug-resistant epilepsy who was diagnosed with a de novo mutation in the CDKL5 gene. First seizures developed in the fifth week of life and have progressed steadily since then. The child's psychomotor development was strongly delayed, and generalized hypotonia was noticed since birth. Brain MRI showed areas of incomplete myelination, posterior narrowing of the corpus callosum, a pineal cyst of up to 3 mm, and open islet lids. Intensive antiseizure medications (ASMs), a ketogenic diet, and steroid therapy were not successful. Short-term improvement was achieved with the implantation of a vagal nerve stimulator (VNS). Due to the progressive course of the disease, the boy requires frequent modification of ASMs.
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Affiliation(s)
- Małgorzata Rodak
- Students’ Scientific Society, Department of Pediatric Neurology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
| | - Mariola Jonderko
- Students’ Scientific Society, Department of Pediatric Neurology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
| | - Patrycja Rozwadowska
- Students’ Scientific Society, Department of Pediatric Neurology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
| | - Magdalena Machnikowska-Sokołowska
- Department of Diagnostic Imaging, Radiology and Nuclear Medicine, Faculty of Medical Science in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
| | - Justyna Paprocka
- Department of Pediatric Neurology, Faculty of Medical Sciences in Katowice, Medical University of Silesia, 40-752 Katowice, Poland
- Correspondence:
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10
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Mahdiannasser M, Rashidi-Nezhad A, Badv RS, Akrami SM. Exploring the genetic etiology of drug-resistant epilepsy: incorporation of exome sequencing into practice. Acta Neurol Belg 2022; 122:1457-1468. [PMID: 36127562 DOI: 10.1007/s13760-022-02095-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 09/05/2022] [Indexed: 11/25/2022]
Abstract
BACKGROUND By affecting about 50 million people worldwide, epilepsy is considered a global concern in neurology. Intolerable enough, up to ¼ of all patients do not respond to antiepileptic drugs and have recurring seizures. Therefore, revealing the underlying etiology is quite demanding in a clinical context to improve diagnosis and disease management. METHODS Initially, 85 patients suspected of epilepsy underwent thorough clinical and paraclinical evaluation and 24 individuals with drug-resistant epilepsy entered the study. Using whole-exome sequencing, the genetic etiology of drug-resistant epilepsy was investigated and discerned whether this method could facilitate the management of drug-resistant epilepsy through personalized medicine. Eventually, functional annotation was performed and drug-gene interaction networks were constructed to find potential therapeutic targets. RESULTS We found eleven novel variants in various genes including IRF2BPL, ST3GAL3, and GPAA1, for which a few epilepsy-related variants are available in public databases. The overall diagnostic yield for likely pathogenic and pathogenic variants and the detection rate of novel variants were 25% and 84.6%, respectively. Based on the results, two patients were considered potential candidates for personalized medicine. The highest number of interaction with drugs was demonstrated for SCN1A, SCN2A, and GRIN2A genes. CONCLUSIONS This study highlighted the importance of consanguineous marriage in drug-resistant epilepsy and suggested the possibility of reduced penetrance and variable expressivity in some of the autosomal dominant cases. We also suggest that whole-exome sequencing could facilitate personalized management of drug-resistant epilepsy. Regarding drug-gene interactions, some genes such as SCN1A and SCN2A might serve as therapeutic targets in drug-resistant epilepsy.
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Affiliation(s)
- Mojdeh Mahdiannasser
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Poursina St., P.O. Box:14176-13151, Tehran, Iran
| | - Ali Rashidi-Nezhad
- Maternal, Fetal and Neonatal Research Center, Family Health Research Institute, Tehran University of Medical Sciences, Tehran, Iran.,Genetics Ward, Yas Hospital Complex, Tehran University of Medical Sciences, Tehran, Iran
| | - Reza Shervin Badv
- Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran
| | - Seyed Mohammad Akrami
- Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Poursina St., P.O. Box:14176-13151, Tehran, Iran.
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11
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Frasca A, Pavlidou E, Bizzotto M, Gao Y, Balestra D, Pinotti M, Dahl HA, Mazarakis ND, Landsberger N, Kinali M. Not Just Loss-of-Function Variations: Identification of a Hypermorphic Variant in a Patient With a CDKL5 Missense Substitution. Neurol Genet 2022; 8:e666. [PMID: 35280940 PMCID: PMC8906656 DOI: 10.1212/nxg.0000000000000666] [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: 07/07/2021] [Accepted: 12/21/2021] [Indexed: 11/15/2022]
Abstract
Background and Objectives CDKL5 deficiency disorder (CDD) is a neurodevelopmental encephalopathy characterized by early-onset epilepsy and impaired psychomotor development. Variations in the X-linked CDKL5 gene coding for a kinase cause CDD. Molecular genetics has proved that almost all pathogenic missense substitutions localize in the N-terminal catalytic domain, therefore underlining the importance for brain development and functioning of the kinase activity. CDKL5 also features a long C-terminal domain that acts as negative regulator of the enzymatic activity and modulates its subcellular distribution. CDD is generally attributed to loss-of-function variations, whereas the clinical consequences of increased CDKL5 activity remain uncertain. We have identified a female patient characterized by mild epilepsy and neurologic symptoms, harboring a novel c.2873C>G nucleotide substitution, leading to the missense variant p.(Thr958Arg). To increase our comprehension of genetic variants in CDKL5-associated neurologic disorders, we have characterized the molecular consequences of the identified substitution. Methods MRI and video EEG telemetry were used to describe brain activity and capture seizure. The Bayley III test was used to evaluate the patient development. Reverse transcriptase PCR was used to analyze whether the identified nucleotide variant affects messenger RNA stability and/or splicing. The X chromosome inactivation pattern was analyzed determining the DNA methylation status of the androgen receptor (AR) gene and by sequencing of expressed alleles. Western blotting was used to investigate whether the novel Thr958Arg substitution affects the stability and/or enzymatic activity of CDKL5. Immunofluorescence was used to define whether CDKL5 subcellular distribution is affected by the Thr958Arg substitution. Results Our data suggested that the proband tends toward a skewed X chromosome inactivation pattern in favor of the novel variant. The molecular investigation revealed that the p.(Thr958Arg) substitution leads to a significant increase in the autophosphorylation of both the TEY motif and residue Tyr171 of CDKL5, as well as in the phosphorylation of the target protein MAP1S, indicating an hyperactivation of CDKL5. This occurs without evidently affecting the kinase subcellular distribution. Discussion Our data provide a strong indication that the c.2873C>G nucleotide substitution represents an hypermorphic pathogenic variation of CDKL5, therefore highlighting the importance of a tight control of CDKL5 activity in the brain.
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Affiliation(s)
- Angelisa Frasca
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Efterpi Pavlidou
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Matteo Bizzotto
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Yunan Gao
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Dario Balestra
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Mirko Pinotti
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Hans Atli Dahl
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Nicholas D Mazarakis
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Nicoletta Landsberger
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
| | - Maria Kinali
- Department of Medical Biotechnology and Translational Medicine (A.F., M.B., N.L.), University of Milan, Italy; Department of Speech and Language Therapy (E.P.), University of Ioannina, Greece; Gene Therapy (Y.G., N.D.M.), Division of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, United Kingdom; Department of Life Sciences and Biotechnology (D.B., M.P.), University of Ferrara, Italy; Amplexa Genetics A/S (H.A.D.), Odense, Denmark; Department of Paediatric Neurology (M.K.), The Portland Hospital, HCA Healthcare UK; and Imperial College (M.K.), London, United Kingdom
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12
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The Genetic Diagnosis of Ultrarare DEEs: An Ongoing Challenge. Genes (Basel) 2022; 13:genes13030500. [PMID: 35328054 PMCID: PMC8953579 DOI: 10.3390/genes13030500] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/04/2022] [Accepted: 03/10/2022] [Indexed: 02/06/2023] Open
Abstract
Epileptic encephalopathies (EEs) and developmental and epileptic encephalopathies (DEEs) are a group of severe early-onset neurodevelopmental disorders (NDDs). In recent years, next-generation equencing (NGS) technologies enabled the discovery of numerous genes involved in these conditions. However, more than 50% of patients remained undiagnosed. A major obstacle lies in the high degree of genetic heterogeneity and the wide phenotypic variability that has characterized these disorders. Interpreting a large amount of NGS data is also a crucial challenge. This study describes a dynamic diagnostic procedure used to investigate 17 patients with DEE or EE with previous negative or inconclusive genetic testing by whole-exome sequencing (WES), leading to a definite diagnosis in about 59% of participants. Biallelic mutations caused most of the diagnosed cases (50%), and a pathogenic somatic mutation resulted in 10% of the subjects. The high diagnostic yield reached highlights the relevance of the scientific approach, the importance of the reverse phenotyping strategy, and the involvement of a dedicated multidisciplinary team. The study emphasizes the role of recessive and somatic variants, new genetic mechanisms, and the complexity of genotype–phenotype associations. In older patients, WES results could end invasive diagnostic procedures and allow a more accurate transition. Finally, an early pursued diagnosis is essential for comprehensive care of patients, precision approach, knowledge of prognosis, patient and family planning, and quality of life.
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13
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Siri B, Varesio C, Freri E, Darra F, Gana S, Mei D, Porta F, Fontana E, Galati G, Solazzi R, Niceta M, Veggiotti P, Alfei E. CDKL5 deficiency disorder in males: Five new variants and review of the literature. Eur J Paediatr Neurol 2021; 33:9-20. [PMID: 33989939 DOI: 10.1016/j.ejpn.2021.04.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 04/18/2021] [Accepted: 04/24/2021] [Indexed: 11/30/2022]
Abstract
The X-linked Cyclin-Dependent Kinase-Like 5 (CDKL5) gene encodes a serine-threonine kinase highly expressed in the developing brain. Loss of function of CDKL5 is pointed out to underlie the CDKL5 Deficiency Disorder (CDD), an X-linked dominant disease characterized by early-onset epileptic encephalopathy and developmental delay, usually affecting females more than males. To the best to our knowledge, only 45 males with CDD have been reported so far. Type and position of CDKL5 variants with different impact on the protein are reported to influence the clinical presentation. X-chromosome inactivation occurring in females and post-zygotic mosaicism in males are also believed to contribute to this variability. Based on these issues, genotype-phenotype correlations are still challenging. Here, we describe clinical features of five additional affected males with unreported CDKL5 variants, expanding the molecular spectrum of the disorder. We also reviewed the clinical profile of the previously reported 45 males with molecularly confirmed CDD. Severe developmental delay, cortical visual impairment, and early-onset refractory epilepsy characterize the CDD picture in males. By assessing the molecular spectrum, we confirm that germ-line truncating CDKL5 variants, equally distributed across the coding sequence, are the most recurrent mutations in CDD, and cause the worsen phenotype. While recurrence and relevance of missense substitutions within C-terminal remain still debated, disease-causing missense changes affecting the N-terminal catalytic domain correlate to a severe clinical phenotype. Finally, our data provide evidence that post-zygotic CDKL5 mosaicism may result in milder phenotypes and, at least in a subset of subjects, in variable response to antiepileptic treatments.
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Affiliation(s)
- Barbara Siri
- Department of Paediatrics, Ospedale Infantile Regina Margherita, University of Torino, Italy; Division of Metabolism, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | - Costanza Varesio
- Department of Child Neurology and Psychiatry, IRCCS Mondino Foundation, Italy; Department of Brain and Behavioral Sciences, University of Pavia, Italy.
| | - Elena Freri
- Department of Paediatric Neuroscience, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Francesca Darra
- Child Neuropsychiatry, Department of Surgical Sciences, Dentistry, Gynecology and Paediatrics, University of Verona, AOUI Verona, Verona, Italy
| | - Simone Gana
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Davide Mei
- Pediatric Neurology, Neurogenetics and Neurobiology Unit and Laboratories, Children's Hospital A. Meyer-University of Florence, Italy
| | - Francesco Porta
- Department of Paediatrics, AOU Città della Salute e della Scienza di Torino, University of Torino, Italy
| | - Elena Fontana
- Child Neuropsychiatry, Department of Surgical Sciences, Dentistry, Gynecology and Paediatrics, University of Verona, AOUI Verona, Verona, Italy
| | - Giulia Galati
- Child Neuropsychiatry, Department of Surgical Sciences, Dentistry, Gynecology and Paediatrics, University of Verona, AOUI Verona, Verona, Italy
| | - Roberta Solazzi
- Department of Paediatric Neuroscience, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Marcello Niceta
- Genetics and Rare Diseases Research Division, Ospedale Pediatrico Bambino Gesù, IRCCS, Rome, Italy
| | - Pierangelo Veggiotti
- L. Sacco Department of Biomedical and Clinical Sciences, University of Milan, Milan, Italy; Paediatric Neurology Unit V. Buzzi Children's Hospital Milan, Italy
| | - Enrico Alfei
- Paediatric Neurology Unit V. Buzzi Children's Hospital Milan, Italy
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Kluckova D, Kolnikova M, Medova V, Bognar C, Foltan T, Svecova L, Gnip A, Kadasi L, Soltysova A, Ficek A. Clinical manifestation of CDKL5 deficiency disorder and identified mutations in a cohort of Slovak patients. Epilepsy Res 2021; 176:106699. [PMID: 34229227 DOI: 10.1016/j.eplepsyres.2021.106699] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2021] [Revised: 06/06/2021] [Accepted: 06/17/2021] [Indexed: 11/16/2022]
Abstract
CDKL5 deficiency disorder (CDD) is an independent clinical entity associated with early-onset encephalopathy, which is often considered the type of epileptic encephalopathy with CDKL5 mutation also found in children diagnosed with early-onset seizure (Hanefeld) type of Rett syndrome, epileptic spasms, West syndrome, Lennox-Gastaut syndrome, or autism. Since early seizure onset is a prominent feature, in this study, a cohort of 54 unrelated patients consisting of 26 males and 28 females was selected for CDKL5 screening, with seizures presented before 12 months of age being the only clinical criterion. Five patients were found to have pathogenic or likely pathogenic variants in CDKL5 while 1 was found to have a variant of uncertain significance (p.L522V). Although CDKL5 variants are more frequently identified in female patients, we identified three male and three female patients (11.1 %, 6/54) in this study. Missense variant with unknown inheritance (p.L522V), de novo missense variant (p.E60 K), two de novo splicing (IVS15 + 1G > A, IVS16 + 2 T > A), and one de novo nonsense variant p.W125* were identified using Sanger sequencing. Whole exome analysis approach revealed de novo frameshift variant c.1247_1248delAG in a mosaic form in one of the males. Patient clinical features are reviewed and compared to those previously described in related literature. Variable clinical features were presented in CDKL5 positive patients characterised in this study. In addition to more common features, such as early epileptic seizures, severe intellectual disability, and gross motor impairment, inappropriate laughing/screaming spells and hypotonia appeared at the age of 1 year in all patients, regardless of the type of CDKL5 mutation or sex. All three CDKL5 positive males from our cohort were initially diagnosed with West syndrome, which suggests that the CDKL5 gene mutations are a significant cause of West syndrome phenotype, and also indicate the overlapping characteristics of these two clinical entities.
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Affiliation(s)
- Daniela Kluckova
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, Bratislava, 842 15, Slovakia
| | - Miriam Kolnikova
- Department of Paediatric Neurology, Faculty of Medicine, Comenius University and National Institute of Children's Diseases, Limbova 1, 833 40, Bratislava, Slovakia
| | - Veronika Medova
- Institute for Clinical and Translational Research, Biomedical Research Centre, Slovak Academy of Sciences, Dubravska cesta 9, 845 05, Bratislava, Slovakia
| | - Csaba Bognar
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, Bratislava, 842 15, Slovakia
| | - Tomas Foltan
- Department of Paediatric Neurology, Faculty of Medicine, Comenius University and National Institute of Children's Diseases, Limbova 1, 833 40, Bratislava, Slovakia
| | - Lucia Svecova
- Department of Paediatric Neurology, Faculty of Medicine, Comenius University and National Institute of Children's Diseases, Limbova 1, 833 40, Bratislava, Slovakia
| | - Andrej Gnip
- Medirex a.s., MEDIREX GROUP, Holubyho 35, 902 01, Pezinok, Slovakia
| | - Ludevit Kadasi
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, Bratislava, 842 15, Slovakia; Institute for Clinical and Translational Research, Biomedical Research Centre, Slovak Academy of Sciences, Dubravska cesta 9, 845 05, Bratislava, Slovakia
| | - Andrea Soltysova
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, Bratislava, 842 15, Slovakia; Institute for Clinical and Translational Research, Biomedical Research Centre, Slovak Academy of Sciences, Dubravska cesta 9, 845 05, Bratislava, Slovakia
| | - Andrej Ficek
- Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, Ilkovicova 6, Bratislava, 842 15, Slovakia.
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15
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Phenotypic analysis of catastrophic childhood epilepsy genes. Commun Biol 2021; 4:680. [PMID: 34083748 PMCID: PMC8175701 DOI: 10.1038/s42003-021-02221-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Accepted: 05/17/2021] [Indexed: 01/06/2023] Open
Abstract
Genetic engineering techniques have contributed to the now widespread use of zebrafish to investigate gene function, but zebrafish-based human disease studies, and particularly for neurological disorders, are limited. Here we used CRISPR-Cas9 to generate 40 single-gene mutant zebrafish lines representing catastrophic childhood epilepsies. We evaluated larval phenotypes using electrophysiological, behavioral, neuro-anatomical, survival and pharmacological assays. Local field potential recordings (LFP) were used to screen ∼3300 larvae. Phenotypes with unprovoked electrographic seizure activity (i.e., epilepsy) were identified in zebrafish lines for 8 genes; ARX, EEF1A, GABRB3, GRIN1, PNPO, SCN1A, STRADA and STXBP1. We also created an open-source database containing sequencing information, survival curves, behavioral profiles and representative electrophysiology data. We offer all zebrafish lines as a resource to the neuroscience community and envision them as a starting point for further functional analysis and/or identification of new therapies. Griffin et al used CRISPR-Cas9 to generate 40 single-gene mutant zebrafish lines representing childhood epilepsies for which they evaluated larval phenotypes using electrophysiological, behavioral, neuro-anatomical, survival and pharmacological assays. Their study provides a useful resource for the future functional analysis and/or identification of potential anti-epileptic therapies.
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Ciccia LM, Scalia B, Venti V, Pizzo F, Pappalardo MG, La Mendola FMC, Falsaperla R, Praticò AD. CDKL5 Gene: Beyond Rett Syndrome. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1727141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Abstract
CDKL5 is a gene located in the X-chromosome (Xp22) encoding a serine/threonine kinase involved in various signaling pathways, implicated in cell proliferation, axon development, dendrite growth, synapse formation, and maintenance. Mutations occurring in this gene have been associated with drug-resistant early-onset epilepsy, with multiple seizures type, and deep cognitive and motor development delay with poor or absent speech, ataxic gait or inability to walk, hand stereotypies and in a few cases decrement of head growth. Many aspects remain unclear about the CDKL5 deficiency disorders, research will be fundamental to better understand the pathogenesis of neurological damage and consequently developed more targeted and profitable therapies, as there is not, at the present, a gene-based treatment and the seizures are in most of the cases drug resistant. In this article, we summarize the actual knowledge about CDKL5 gene function and mostly the consequence given by its dysfunction, also examining the possible therapeutic approaches.
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Affiliation(s)
- Lina Maria Ciccia
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Bruna Scalia
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Valeria Venti
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Francesco Pizzo
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Maria Grazia Pappalardo
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | | | - Raffaele Falsaperla
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
- Unit of Neonatal Intensive Care and Neonatology, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
| | - Andrea D. Praticò
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
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17
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Scalia B, Venti V, Ciccia LM, Criscione R, Lo Bianco M, Sciuto L, Falsaperla R, Zanghì A, Praticò AD. Aristaless-Related Homeobox (ARX): Epilepsy Phenotypes beyond Lissencephaly and Brain Malformations. JOURNAL OF PEDIATRIC NEUROLOGY 2021. [DOI: 10.1055/s-0041-1727140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AbstractThe Aristaless-related homeobox (ARX) transcription factor is involved in the development of GABAergic and cholinergic neurons in the forebrain. ARX mutations have been associated with a wide spectrum of neurodevelopmental disorders in humans and are responsible for both malformation (in particular lissencephaly) and nonmalformation complex phenotypes. The epilepsy phenotypes related to ARX mutations are West syndrome and X-linked infantile spasms, X-linked myoclonic epilepsy with spasticity and intellectual development and Ohtahara and early infantile epileptic encephalopathy syndrome, which are related in most of the cases to intellectual disability and are often drug resistant. In this article, we shortly reviewed current knowledge of the function of ARX with a particular attention on its consequences in the development of epilepsy during early childhood.
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Affiliation(s)
- Bruna Scalia
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Valeria Venti
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Lina M. Ciccia
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Roberta Criscione
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Manuela Lo Bianco
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Laura Sciuto
- Pediatrics Postgraduate Residency Program, Section of Pediatrics and Child Neuropsychiatry, Department of Clinical and Experimental Medicine, University of Catania, Catania, Italy
| | - Raffaele Falsaperla
- Unit of Pediatrics and Pediatric Emergency, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
- Neonatal Intensive Care unit and Neonatology, University Hospital “Policlinico Rodolico-San Marco,” Catania, Italy
| | - Antonio Zanghì
- Department of Medical and Surgical Sciences and Advanced Technology “G.F. Ingrassia,” University of Catania, Catania, Italy
| | - Andrea D. Praticò
- Unit of Rare Diseases of the Nervous System in Childhood, Department of Clinical and Experimental Medicine, Section of Pediatrics and Child Neuropsychiatry, University of Catania, Catania, Italy
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18
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Carli S, Chaabane L, Butti C, De Palma C, Aimar P, Salio C, Vignoli A, Giustetto M, Landsberger N, Frasca A. In vivo magnetic resonance spectroscopy in the brain of Cdkl5 null mice reveals a metabolic profile indicative of mitochondrial dysfunctions. J Neurochem 2021; 157:1253-1269. [PMID: 33448385 DOI: 10.1111/jnc.15300] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 10/24/2020] [Accepted: 01/07/2021] [Indexed: 12/12/2022]
Abstract
Mutations in the X-linked CDKL5 gene cause CDKL5 deficiency disorder (CDD), a severe neurodevelopmental condition mainly characterized by infantile epileptic encephalopathy, intellectual disability, and autistic features. The molecular mechanisms underlying the clinical symptoms remain largely unknown and the identification of reliable biomarkers in animal models will certainly contribute to increase our comprehension of CDD as well as to assess the efficacy of therapeutic strategies. Here, we used different Magnetic Resonance (MR) methods to disclose structural, functional, or metabolic signatures of Cdkl5 deficiency in the brain of adult mice. We found that loss of Cdkl5 does not cause cerebral atrophy but affects distinct brain areas, particularly the hippocampus. By in vivo proton-MR spectroscopy (MRS), we revealed in the Cdkl5 null brain a metabolic dysregulation indicative of mitochondrial dysfunctions. Accordingly, we unveiled a significant reduction in ATP levels and a decrease in the expression of complex IV of mitochondrial electron transport chain. Conversely, the number of mitochondria appeared preserved. Importantly, we reported a significant defect in the activation of one of the major regulators of cellular energy balance, the adenosine monophosphate-activated protein kinase (AMPK), that might contribute to the observed metabolic impairment and become an interesting therapeutic target for future preclinical trials. In conclusion, MRS revealed in the Cdkl5 null brain the presence of a metabolic dysregulation suggestive of a mitochondrial dysfunction that permitted to foster our comprehension of Cdkl5 deficiency and brought our interest towards targeting mitochondria as therapeutic strategy for CDD.
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Affiliation(s)
- Sara Carli
- Neuroscience Division, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Linda Chaabane
- Institute of Experimental Neurology (INSPE) and Experimental Imaging Center (CIS), IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Clarissa Butti
- Neuroscience Division, IRCCS San Raffaele Scientific Institute, Milan, Italy.,Molecular Nociception Group, Wolfson Institute for Biomedical Research (WIBR), University College London, London, UK
| | - Clara De Palma
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Segrate (Milan), Italy
| | - Patrizia Aimar
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
| | - Chiara Salio
- Department of Veterinary Sciences, University of Turin, Grugliasco, Italy
| | - Aglaia Vignoli
- Epilepsy Center-Child Neuropsychiatric Unit, ASST Santi Paolo e Carlo, Department of Health Sciences, University of Milan, Milan, Italy
| | - Maurizio Giustetto
- Department of Neuroscience, University of Turin, Turin, Italy.,National Institute of Neuroscience-Italy, Turin, Italy
| | - Nicoletta Landsberger
- Neuroscience Division, IRCCS San Raffaele Scientific Institute, Milan, Italy.,Department of Medical Biotechnology and Translational Medicine, University of Milan, Segrate (Milan), Italy
| | - Angelisa Frasca
- Department of Medical Biotechnology and Translational Medicine, University of Milan, Segrate (Milan), Italy
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Terzic B, Cui Y, Edmondson AC, Tang S, Sarmiento N, Zaitseva D, Marsh ED, Coulter DA, Zhou Z. X-linked cellular mosaicism underlies age-dependent occurrence of seizure-like events in mouse models of CDKL5 deficiency disorder. Neurobiol Dis 2021; 148:105176. [PMID: 33197557 PMCID: PMC7856307 DOI: 10.1016/j.nbd.2020.105176] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Accepted: 11/08/2020] [Indexed: 11/29/2022] Open
Abstract
CDKL5 deficiency disorder (CDD) is an infantile, epileptic encephalopathy presenting with early-onset seizures, intellectual disability, motor impairment, and autistic features. The disorder has been linked to mutations in the X-linked CDKL5, and mouse models of the disease recapitulate several aspects of CDD symptomology, including learning and memory impairments, motor deficits, and autistic-like features. Although early-onset epilepsy is one of the hallmark features of CDD, evidence of spontaneous seizure activity has only recently been described in Cdkl5-deficient heterozygous female mice, but the etiology, prevalence, and sex-specificity of this phenotype remain unknown. Here, we report the first observation of disturbance-associated seizure-like events in heterozygous female mice across two independent mouse models of CDD: Cdkl5 knockout mice and CDKL5 R59X knock-in mice. We find that both the prevalence and severity of this phenotype increase with aging, with a median onset around 28 weeks of age. Similar seizure-like events are not observed in hemizygous knockout male or homozygous knockout female littermates, suggesting that X-linked cellular mosaicism is a driving factor underlying these seizure-like events. Together, these findings not only contribute to our understanding of the effects of CDKL5 loss on seizure susceptibility, but also document a novel, pre-clinical phenotype for future therapeutic investigation.
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Affiliation(s)
- Barbara Terzic
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Yue Cui
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Andrew C Edmondson
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Division of Human Genetics, Department of Pediatrics, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Sheng Tang
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Division of Child Neurology and CHOP Research Institute, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Nicolas Sarmiento
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Daria Zaitseva
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Eric D Marsh
- Departments of Neuroscience, Neurology, and Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Division of Child Neurology and CHOP Research Institute, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Douglas A Coulter
- Departments of Neuroscience, Neurology, and Pediatrics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Division of Child Neurology and CHOP Research Institute, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Zhaolan Zhou
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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20
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Cutri-French C, Armstrong D, Saby J, Gorman C, Lane J, Fu C, Peters SU, Percy A, Neul JL, Marsh ED. Comparison of Core Features in Four Developmental Encephalopathies in the Rett Natural History Study. Ann Neurol 2020; 88:396-406. [PMID: 32472944 DOI: 10.1002/ana.25797] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Rett syndrome, CDKL5-deficiency disorder, FOXG1 disorder, and MECP2 duplication disorder are developmental encephalopathies with shared and distinct features. Although they are historically linked, no direct comparison has been performed. The first head-to-head comparison of clinical features in these conditions is presented. METHODS Comprehensive clinical information was collected from 793 individuals enrolled in the Rett and Rett-Related Disorders Natural History Study. Clinical features including clinical severity, regression, and seizures were cross-sectionally compared between diagnoses to test the hypothesis that these are 4 distinct disorders. RESULTS Distinct patterns of clinical severity, seizure onset age, and regression were present. Individuals with CDKL5-deficency disorder were the most severely affected and had the youngest age at seizure onset (2 months), whereas children with MECP2 duplication syndrome had the oldest median age at seizure onset (64 months) and lowest severity scores. Rett syndrome and FOGX1 were intermediate in both features. Smaller head circumference correlates with increased severity in all disorders and earlier age at seizure onset in MECP2 duplication syndrome. Developmental regression occurred in all Rett syndrome participants (median = 18 months) but only 23 to 34% of the other disorders. Seizure incidence prior to the baseline visit was highest for CDKL5 deficiency disorder (96.2%) and lowest for Rett syndrome (47.5%). Other clinical features including seizure types and frequency differed among groups. INTERPRETATION Although these developmental encephalopathies share many clinical features, clear differences in severity, regression, and seizures warrant considering them as unique disorders. These results will aid in the development of disease-specific severity scales, precise therapeutics, and future clinical trials. ANN NEUROL 2020;88:396-406.
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Affiliation(s)
- Clare Cutri-French
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
| | - Dallas Armstrong
- Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Joni Saby
- Division of Radiology Research, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Casey Gorman
- Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Jane Lane
- Department of Pediatrics, Civitan International Research Center, University of Alabama at Birmingham, Birmingham, Alabama
| | - Cary Fu
- Department of Pediatrics, Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Sarika U Peters
- Department of Pediatrics, Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Alan Percy
- Department of Pediatrics, Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, Tennessee
| | - Jeffrey L Neul
- Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - Eric D Marsh
- Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania.,Division of Child Neurology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
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21
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Thai MHN, Gardner A, Redpath L, Mattiske T, Dearsley O, Shaw M, Vulto-van Silfhout AT, Pfundt R, Dixon J, McGaughran J, Pérez-Jurado LA, Gécz J, Shoubridge C. Constraint and conservation of paired-type homeodomains predicts the clinical outcome of missense variants of uncertain significance. Hum Mutat 2020; 41:1407-1424. [PMID: 32383243 DOI: 10.1002/humu.24034] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 02/26/2020] [Accepted: 05/03/2020] [Indexed: 12/30/2022]
Abstract
The need to interpret the pathogenicity of novel missense variants of unknown significance identified in the homeodomain of X-chromosome aristaless-related homeobox (ARX) gene prompted us to assess the utility of conservation and constraint across these domains in multiple genes compared to conventional in vitro functional analysis. Pathogenic missense variants clustered in the homeodomain of ARX contribute to intellectual disability (ID) and epilepsy, with and without brain malformation in affected males. Here we report novel c.1112G>A, p.Arg371Gln and c.1150C>T, p.Arg384Cys variants in male patients with ID and severe seizures. The third case of a male patient with a c.1109C>T, p.Ala370Val variant is perhaps the first example of ID and autism spectrum disorder (ASD), without seizures or brain malformation. We compiled data sets of pathogenic variants from ClinVar and presumed benign variation from gnomAD and demonstrated that the high levels of sequence conservation and constraint of benign variation within the homeodomain impacts upon the ability of publicly available in silico prediction tools to accurately discern likely benign from likely pathogenic variants in these data sets. Despite this, considering the inheritance patterns of the genes and disease variants with the conservation and constraint of disease variants affecting the homeodomain in conjunction with current clinical assessments may assist in predicting the pathogenicity of missense variants, particularly for genes with autosomal recessive and X-linked patterns of disease inheritance, such as ARX. In vitro functional analysis demonstrates that the transcriptional activity of all three variants was diminished compared to ARX-Wt. We review the associated phenotypes of the published cases of patients with ARX homeodomain variants and propose expansion of the ARX-related phenotype to include severe ID and ASD without brain malformations or seizures. We propose that the use of the constraint and conservation data in conjunction with consideration of the patient phenotype and inheritance pattern may negate the need for the experimental functional validation currently required to achieve a diagnosis.
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Affiliation(s)
- Monica H N Thai
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Alison Gardner
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | - Laura Redpath
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Tessa Mattiske
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
| | - Oliver Dearsley
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | - Marie Shaw
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia
| | | | - Rolph Pfundt
- Department of Human Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Joanne Dixon
- Genetic Health Service NZ-South Island Hub, Christchurch Hospital, Christchurch, New Zealand
| | - Julie McGaughran
- Genetic Health Queensland, MNHHS, Brisbane and School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
| | - Luis A Pérez-Jurado
- Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia.,South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia.,South Australian Clinical Genetics Service, SA Pathology, Adelaide, South Australia, Australia.,Hospital del Mar Research Institute, Network Research Centre for Rare Diseases and Universitat Pompeu Fabra, Barcelona, Spain
| | - Jozef Gécz
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia.,South Australian Health and Medical Research Institute, Adelaide, South Australia, Australia
| | - Cheryl Shoubridge
- Adelaide Medical School, University of Adelaide, Adelaide, South Australia, Australia.,Robinson Research Institute, University of Adelaide, Adelaide, South Australia, Australia
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22
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Gao Y, Irvine EE, Eleftheriadou I, Naranjo CJ, Hearn-Yeates F, Bosch L, Glegola JA, Murdoch L, Czerniak A, Meloni I, Renieri A, Kinali M, Mazarakis ND. Gene replacement ameliorates deficits in mouse and human models of cyclin-dependent kinase-like 5 disorder. Brain 2020; 143:811-832. [DOI: 10.1093/brain/awaa028] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 11/15/2019] [Accepted: 12/13/2019] [Indexed: 01/04/2023] Open
Abstract
Abstract
Cyclin-dependent kinase-like 5 disorder is a severe neurodevelopmental disorder caused by mutations in the X-linked cyclin-dependent kinase-like 5 (CDKL5) gene. It predominantly affects females who typically present with severe early epileptic encephalopathy, global developmental delay, motor dysfunction, autistic features and sleep disturbances. To develop a gene replacement therapy, we initially characterized the human CDKL5 transcript isoforms expressed in the brain, neuroblastoma cell lines, primary astrocytes and embryonic stem cell-derived cortical interneurons. We found that the isoform 1 and to a lesser extent the isoform 2 were expressed in human brain, and both neuronal and glial cell types. These isoforms were subsequently cloned into recombinant adeno-associated viral (AAV) vector genome and high-titre viral vectors were produced. Intrajugular delivery of green fluorescence protein via AAV vector serotype PHP.B in adult wild-type male mice transduced neurons and astrocytes throughout the brain more efficiently than serotype 9. Cdkl5 knockout male mice treated with isoform 1 via intrajugular injection at age 28–30 days exhibited significant behavioural improvements compared to green fluorescence protein-treated controls (1012 vg per animal, n = 10 per group) with PHP.B vectors. Brain expression of the isoform 1 transgene was more abundant in hindbrain than forebrain and midbrain. Transgene brain expression was sporadic at the cellular level and most prominent in hippocampal neurons and cerebellar Purkinje cells. Correction of postsynaptic density protein 95 cerebellar misexpression, a major fine cerebellar structural abnormality in Cdkl5 knockout mice, was found in regions of high transgene expression within the cerebellum. AAV vector serotype DJ efficiently transduced CDKL5-mutant human induced pluripotent stem cell-derived neural progenitors, which were subsequently differentiated into mature neurons. When treating CDKL5-mutant neurons, isoform 1 expression led to an increased density of synaptic puncta, while isoform 2 ameliorated the calcium signalling defect compared to green fluorescence protein control, implying distinct functions of these isoforms in neurons. This study provides the first evidence that gene therapy mediated by AAV vectors can be used for treating CDKL5 disorder.
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Affiliation(s)
- Yunan Gao
- Gene Therapy, Section of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, London W12 0NN, UK
| | - Elaine E Irvine
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, Imperial College London, London W12 0NN, UK
| | - Ioanna Eleftheriadou
- Gene Therapy, Section of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, London W12 0NN, UK
| | - Carlos Jiménez Naranjo
- Gene Therapy, Section of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, London W12 0NN, UK
| | - Francesca Hearn-Yeates
- Gene Therapy, Section of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, London W12 0NN, UK
| | - Leontien Bosch
- Gene Therapy, Section of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, London W12 0NN, UK
| | - Justyna A Glegola
- Metabolic Signalling Group, MRC London Institute of Medical Sciences, Imperial College London, London W12 0NN, UK
| | - Leah Murdoch
- CBS Imperial College London, Hammersmith Campus, London W12 0NN, UK
| | | | - Ilaria Meloni
- Medical Genetics, Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Alessandra Renieri
- Medical Genetics, Department of Medical Biotechnologies, University of Siena, Siena, Italy
| | - Maria Kinali
- The Portland Hospital, 205-209 Great Portland Street, London, W1W 5AH, UK
| | - Nicholas D Mazarakis
- Gene Therapy, Section of Neuroscience, Department of Brain Sciences, Faculty of Medicine, Imperial College London, Hammersmith Campus, London W12 0NN, UK
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23
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CDKL5 Deficiency Disorder-A Complex Epileptic Encephalopathy. Brain Sci 2020; 10:brainsci10020107. [PMID: 32079229 PMCID: PMC7071516 DOI: 10.3390/brainsci10020107] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 02/11/2020] [Accepted: 02/13/2020] [Indexed: 12/31/2022] Open
Abstract
CDKL5 deficiency disorder (CDD) is a complex of clinical symptoms resulting from the presence of non-functional CDKL5 protein, i.e., serine-threonine kinase (previously referred to as STK9), or its complete absence. The clinical picture is characterized by epileptic seizures (that start within the first three months of life and most often do not respond to pharmacological treatment), epileptic encephalopathy secondary to seizures, and retardation of psychomotor development, which are often observed already in the first months of life. Due to the fact that CDKL5 is located on the X chromosome, the prevalence of CDD among women is four times higher than in men. However, the course is usually more severe among male patients. Recently, many clinical centers have analyzed this condition and provided knowledge on the function of CDKL5 protein, the natural history of the disease, therapeutic options, and their effectiveness and prognosis. The International CDKL5 Disorder Database was established in 2012, which focuses its activity on expanding knowledge related to this condition and disseminating such knowledge to the families of patients.
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24
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Liang JS, Huang H, Wang JS, Lu JF. Phenotypic manifestations between male and female children with CDKL5 mutations. Brain Dev 2019; 41:783-789. [PMID: 31122804 DOI: 10.1016/j.braindev.2019.05.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 04/17/2019] [Accepted: 05/07/2019] [Indexed: 12/29/2022]
Abstract
BACKGROUND Cyclin-dependent kinase-like 5 (CDKL5), which maps to chromosome Xp22.13 and contains 20 coding exons, has been recognized as the gene responsible for early-onset epileptic encephalopathy (EoEE). A retrospective study is carried out to analyze potential genotypic and phenotypic differences between male and female patients with CDKL5 mutations. MATERIALS AND METHODS Targeted next-generation DNA sequencing was employed to search for mutations in patients with cryptogenic EE. A total of 44 patients with EoEE/infantile spasms (ISs)/West syndrome were enrolled for pathogenic mutation screening. The clinical phenotypes of patients with CDKL5 mutations were analyzed and compared with those of 166 published cases. RESULTS One novel and three recurrent mutations were found in four enrolled patients (two boys and two girls). One female patient had partial seizures during the early infantile period and epileptic spasms and tonic seizures several weeks thereafter. The other female patient had IS with hypsarrhythmia. The two male patients had IS without typical hypsarrhythmia and were bedridden. Brain MRIs of the male patients revealed brain atrophy and white matter hyperintensity. The female patients exhibited autistic features with hand stereotypies. CONCLUSION Our study highlights that both girls and boys with IS harbor CDKL5 mutations. Male children with CDKL5 mutations demonstrate a higher frequency of infantile spasms and brain atrophy, whereas female children often exhibit atypical Rett syndrome with EoEE. In addition, male children have a more severe phenotype than female children.
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Affiliation(s)
- Jao-Shwann Liang
- Department of Pediatrics, Far Eastern Memorial Hospital, New Taipei City, Taiwan; School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Nursing, Oriental Institute of Technology, New Taipei City, Taiwan
| | - Hsin Huang
- School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Jinn-Shyan Wang
- School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan
| | - Jyh-Feng Lu
- School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
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25
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Fraser H, Goldman A, Wright R, Banka S. A maternally inherited frameshift
CDKL5
variant in a male with global developmental delay and late‐onset generalized epilepsy. Am J Med Genet A 2019; 179:507-511. [DOI: 10.1002/ajmg.a.40661] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 09/04/2018] [Accepted: 09/21/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Harry Fraser
- Manchester Centre for Genomic MedicineSt Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester Manchester United Kingdom
| | - Amy Goldman
- Manchester Centre for Genomic MedicineSt Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester Manchester United Kingdom
| | - Ronnie Wright
- Manchester Centre for Genomic MedicineSt Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester Manchester United Kingdom
| | - Siddharth Banka
- Manchester Centre for Genomic MedicineSt Mary's Hospital, Manchester University NHS Foundation Trust, Health Innovation Manchester Manchester United Kingdom
- Division of Evolution & Genomic SciencesSchool of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester Manchester United Kingdom
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26
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Sega AG, Mis EK, Lindstrom K, Mercimek-Andrews S, Ji W, Cho MT, Juusola J, Konstantino M, Jeffries L, Khokha MK, Lakhani SA. De novo pathogenic variants in neuronal differentiation factor 2 (NEUROD2) cause a form of early infantile epileptic encephalopathy. J Med Genet 2018; 56:113-122. [PMID: 30323019 DOI: 10.1136/jmedgenet-2018-105322] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Revised: 08/08/2018] [Accepted: 09/22/2018] [Indexed: 12/22/2022]
Abstract
BACKGROUND Early infantile epileptic encephalopathies are severe disorders consisting of early-onset refractory seizures accompanied often by significant developmental delay. The increasing availability of next-generation sequencing has facilitated the recognition of single gene mutations as an underlying aetiology of some forms of early infantile epileptic encephalopathies. OBJECTIVES This study was designed to identify candidate genes as a potential cause of early infantile epileptic encephalopathy, and then to provide genetic and functional evidence supporting patient variants as causative. METHODS We used whole exome sequencing to identify candidate genes. To model the disease and assess the functional effects of patient variants on candidate protein function, we used in vivo CRISPR/Cas9-mediated genome editing and protein overexpression in frog tadpoles. RESULTS We identified novel de novo variants in neuronal differentiation factor 2 (NEUROD2) in two unrelated children with early infantile epileptic encephalopathy. Depleting neurod2 with CRISPR/Cas9-mediated genome editing induced spontaneous seizures in tadpoles, mimicking the patients' condition. Overexpression of wild-type NEUROD2 induced ectopic neurons in tadpoles; however, patient variants were markedly less effective, suggesting that both variants are dysfunctional and likely pathogenic. CONCLUSION This study provides clinical and functional support for NEUROD2 variants as a cause of early infantile epileptic encephalopathy, the first evidence of human disease caused by NEUROD2 variants.
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Affiliation(s)
- Annalisa G Sega
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Emily K Mis
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Kristin Lindstrom
- Division of Genetics and Metabolism, Phoenix Children's Hospital, Phoenix, Arizona, USA
| | - Saadet Mercimek-Andrews
- Genetics and Genome Biology Program, Research Institute, The Hospital for Sick Children, Toronto, Ontario, Canada.,Division of Clinical and Metabolic Genetics, Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.,Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada
| | - Weizhen Ji
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | | | | | - Monica Konstantino
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Lauren Jeffries
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Mustafa K Khokha
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA.,Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Saquib Ali Lakhani
- Pediatric Genomics Discovery Program, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut, USA
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A novel C‐terminal truncated mutation in hCDKL5 protein causing a severe West syndrome: Comparison with previous truncated mutations and genotype/phenotype correlation. Int J Dev Neurosci 2018; 72:22-30. [DOI: 10.1016/j.ijdevneu.2018.09.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 09/12/2018] [Accepted: 09/13/2018] [Indexed: 12/29/2022] Open
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28
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A male case with CDKL5-associated encephalopathy manifesting transient methylmalonic acidemia. Eur J Med Genet 2018; 61:451-454. [DOI: 10.1016/j.ejmg.2018.03.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 02/13/2018] [Accepted: 03/02/2018] [Indexed: 01/20/2023]
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29
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Akamine S, Sagata N, Sakai Y, Kato TA, Nakahara T, Matsushita Y, Togao O, Hiwatashi A, Sanefuji M, Ishizaki Y, Torisu H, Saitsu H, Matsumoto N, Hara T, Sawa A, Kano S, Furue M, Kanba S, Shaw CA, Ohga S. Early-onset epileptic encephalopathy and severe developmental delay in an association with de novo double mutations in NF1 and MAGEL2. Epilepsia Open 2018; 3:81-85. [PMID: 29588991 PMCID: PMC5839317 DOI: 10.1002/epi4.12085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2017] [Indexed: 01/01/2023] Open
Abstract
Advance in the exome-wide sequencing analysis contributes to identifying hundreds of genes that are associated with early-onset epileptic encephalopathy and neurodevelopmental disorders. On the basis of massive sequencing data, functional interactions among different genes are suggested to explain the common molecular pathway underlying the pathogenic process of these disorders. However, the relevance of such interactions with the phenotypic severity or variety in an affected individual remains elusive. In this report, we present a 45-year-old woman with neurofibromatosis type 1 (NF1), infantile-onset epileptic encephalopathy, and severe developmental delay. Whole-exome sequencing identified de novo pathogenic mutations in NF1 and the Schaaf-Yang syndrome-associated gene, MAGEL2. Literature-curated interaction data predicted that NF1 and MAGEL2 proteins were closely connected in this network via their common interacting proteins. Direct conversion of fibroblasts into neurons in vitro showed that neuronal cells from 9 patients with NF1 expressed significantly lower levels of MAGEL2 (54%, p = 0.0047) than those from healthy individuals. These data provide the first evidence that pathogenic mutations of NF1 deregulate the expression of other neurodevelopmental disease-associated genes. De novo mutations in multiple genes may lead to severe developmental phenotypes through their cumulative effects or synergistic interactions.
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Affiliation(s)
- Satoshi Akamine
- Department of Pediatrics Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Noriaki Sagata
- Department of Neuropsychiatry Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Yasunari Sakai
- Department of Pediatrics Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Takahiro A Kato
- Department of Neuropsychiatry Graduate School of Medical Sciences Kyushu University Fukuoka Japan.,Innovation Center for Medical Redox Navigation Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Takeshi Nakahara
- Department of Dermatology Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Yuki Matsushita
- Department of Pediatrics Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Osamu Togao
- Department of Radiology Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Akio Hiwatashi
- Department of Radiology Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Masafumi Sanefuji
- Department of Pediatrics Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Yoshito Ishizaki
- Department of Pediatrics Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Hiroyuki Torisu
- Department of Pediatrics Graduate School of Medical Sciences Kyushu University Fukuoka Japan.,Section of Pediatrics Department of Medicine Fukuoka Dental College Fukuoka Japan
| | - Hirotomo Saitsu
- Department of Human Genetics Yokohama City University Graduate School of Medicine Yokohama Japan.,Department of Biochemistry Hamamatsu University School of Medicine Hamamatsu Japan
| | - Naomichi Matsumoto
- Department of Human Genetics Yokohama City University Graduate School of Medicine Yokohama Japan
| | | | - Akira Sawa
- Departments of Psychiatry Mental Health, Neuroscience, and Biomedical Engineering Johns Hopkins University School of Medicine and Bloomberg School of Public Health Baltimore Maryland U.S.A
| | - Shinichi Kano
- Department of Psychiatry and Behavioral Sciences Johns Hopkins University School of Medicine and Bloomberg School of Public Health Baltimore Maryland U.S.A
| | - Masutaka Furue
- Department of Dermatology Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Shigenobu Kanba
- Department of Neuropsychiatry Graduate School of Medical Sciences Kyushu University Fukuoka Japan
| | - Chad A Shaw
- Department of Molecular and Human Genetics Baylor College of Medicine Houston Texas U.S.A
| | - Shouichi Ohga
- Department of Pediatrics Graduate School of Medical Sciences Kyushu University Fukuoka Japan
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30
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Jackson MR, Lee K, Mattiske T, Jaehne EJ, Ozturk E, Baune BT, O'Brien TJ, Jones N, Shoubridge C. Extensive phenotyping of two ARX polyalanine expansion mutation mouse models that span clinical spectrum of intellectual disability and epilepsy. Neurobiol Dis 2017; 105:245-256. [DOI: 10.1016/j.nbd.2017.05.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 04/30/2017] [Accepted: 05/29/2017] [Indexed: 11/17/2022] Open
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31
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Andrade DM, Bassett AS, Bercovici E, Borlot F, Bui E, Camfield P, Clozza GQ, Cohen E, Gofine T, Graves L, Greenaway J, Guttman B, Guttman-Slater M, Hassan A, Henze M, Kaufman M, Lawless B, Lee H, Lindzon L, Lomax LB, McAndrews MP, Menna-Dack D, Minassian BA, Mulligan J, Nabbout R, Nejm T, Secco M, Sellers L, Shapiro M, Slegr M, Smith R, Szatmari P, Tao L, Vogt A, Whiting S, Carter Snead O. Epilepsy: Transition from pediatric to adult care. Recommendations of the Ontario epilepsy implementation task force. Epilepsia 2017; 58:1502-1517. [PMID: 28681381 DOI: 10.1111/epi.13832] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2017] [Indexed: 01/13/2023]
Abstract
The transition from a pediatric to adult health care system is challenging for many youths with epilepsy and their families. Recently, the Ministry of Health and Long-Term Care of the Province of Ontario, Canada, created a transition working group (TWG) to develop recommendations for the transition process for patients with epilepsy in the Province of Ontario. Herein we present an executive summary of this work. The TWG was composed of a multidisciplinary group of pediatric and adult epileptologists, psychiatrists, and family doctors from academia and from the community; neurologists from the community; nurses and social workers from pediatric and adult epilepsy programs; adolescent medicine physician specialists; a team of physicians, nurses, and social workers dedicated to patients with complex care needs; a lawyer; an occupational therapist; representatives from community epilepsy agencies; patients with epilepsy; parents of patients with epilepsy and severe intellectual disability; and project managers. Three main areas were addressed: (1) Diagnosis and Management of Seizures; 2) Mental Health and Psychosocial Needs; and 3) Financial, Community, and Legal Supports. Although there are no systematic studies on the outcomes of transition programs, the impressions of the TWG are as follows. Teenagers at risk of poor transition should be identified early. The care coordination between pediatric and adult neurologists and other specialists should begin before the actual transfer. The transition period is the ideal time to rethink the diagnosis and repeat diagnostic testing where indicated (particularly genetic testing, which now can uncover more etiologies than when patients were initially evaluated many years ago). Some screening tests should be repeated after the move to the adult system. The seven steps proposed herein may facilitate transition, thereby promoting uninterrupted and adequate care for youth with epilepsy leaving the pediatric system.
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Affiliation(s)
- Danielle M Andrade
- Division of Neurology, Epilepsy Transition Program and Epilepsy Genetics Program, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Anne S Bassett
- Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, Canada
| | - Eduard Bercovici
- Division of Neurology, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Felippe Borlot
- Department of Neurology, Clinical Neurosciences Center University of Utah School of Medicine, Salt Lake City, Utah, U.S.A
| | - Esther Bui
- Division of Neurology, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Peter Camfield
- Division of Pediatric Neurology, Dalhousie University, Halifax, Nova Scotia, Canada
| | | | - Eyal Cohen
- Division of Pediatric Medicine, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada
| | | | | | - Jon Greenaway
- Erin Oak Kids, Centre for Treatment and Development, Toronto, Ontario, Canada
| | - Beverly Guttman
- Provincial Council for Maternal and Child Health, Toronto, Ontario, Canada
| | | | - Ayman Hassan
- Thunder Bay Regional Health Sciences Centre, Thunder Bay, Ontario, Canada
| | - Megan Henze
- Hospital for Sick Children, Toronto, Ontario, Canada
| | - Miriam Kaufman
- Division of Adolescent Medicine, Department of Pediatrics, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada
| | | | - Hannah Lee
- Holland Bloorview Kids Rehabilitation Hospital, Toronto, Ontario, Canada
| | - Lezlee Lindzon
- Epilepsy Program, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Lysa Boissé Lomax
- Division of Neurology, Queens University, Kingston General Hospital, Kingston, Ontario, Canada
| | - Mary Pat McAndrews
- Division of Neuropsychology, University of Toronto, Toronto Western Hospital, Toronto, Ontario, Canada
| | - Dolly Menna-Dack
- LIFEspan Service, Holland Bloorview Kids Rehabilitation Hospital, Toronto, Ontario, Canada
| | - Berge A Minassian
- Pediatric Epileptologist, Division of Pediatric Neurology, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada.,Pediatric Neurology, University of Texas Southwestern and Dallas Children's Medical Center, Dallas, Texas, U.S.A
| | | | - Rima Nabbout
- Pediatric Neurologist, Centre of Reference Epilepsies Rares, Hospital Necker-Enfants Malades, Paris, France
| | - Tracy Nejm
- Parent Representative, London, Ontario, Canada
| | - Mary Secco
- Strategic Initiatives, Epilepsy Support Centre, London, Ontario, Canada
| | | | - Michelle Shapiro
- Division of Neurology, McMaster University, Hamilton Health Sciences Centre, Hamilton, Ontario, Canada
| | | | - Rosie Smith
- Adult Services, Epilepsy Toronto, Toronto, Ontario, Canada
| | - Peter Szatmari
- Child and Youth Mental Health Collaborative, Centre for Addiction and Mental Health, Hospital for Sick Children, University of Toronto, Toronto, Ontario, Canada
| | - Leeping Tao
- Surrey Place Centre, Toronto, Ontario, Canada
| | | | - Sharon Whiting
- Division of Pediatric Neurology, University of Ottawa, Children's Hospital of Eastern Ontario, Ottawa, Ontario, Canada
| | - O Carter Snead
- Division of Pediatric Neurology, University of Toronto, The Hospital for Sick Children, Toronto, Ontario, Canada
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32
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Tapie A, Pi-Denis N, Souto J, Vomero A, Peluffo G, Boidi M, Ciganda M, Curbelo N, Raggio V, Roche L, Pastro L. A novel mutation in the OAR domain of the ARX gene. Clin Case Rep 2017; 5:170-174. [PMID: 28174645 PMCID: PMC5290510 DOI: 10.1002/ccr3.769] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 10/11/2016] [Accepted: 11/16/2016] [Indexed: 11/12/2022] Open
Abstract
Mutations in ARX gene should be considered in patients with mental disability or/and epilepsy. It is an X-linked gene that has pleiotropic effects. Here, we report the case of a boy diagnosed with Ohtahara syndrome. We performed the molecular analysis of the gene and identified a new missense mutation.
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Affiliation(s)
- Alejandra Tapie
- Facultad de Medicina Departamento de Genética Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Natalia Pi-Denis
- Facultad de Medicina Departamento de Genética Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Jorge Souto
- Facultad de Medicina Departamento de Genética Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Alejandra Vomero
- Facultad de Medicina Departamento de Pediatría Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Gabriel Peluffo
- Facultad de Medicina Departamento de Pediatría Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - María Boidi
- Facultad de Medicina Departamento de Genética Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Martín Ciganda
- Facultad de Ciencias Laboratorio de Interacciones Moleculares Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Nicolás Curbelo
- Facultad de Medicina Departamento de Genética Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Victor Raggio
- Facultad de Medicina Departamento de Genética Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Leda Roche
- Facultad de Medicina Departamento de Genética Universidad de la República Oriental del Uruguay Montevideo Uruguay
| | - Lucía Pastro
- Facultad de Medicina Departamento de Genética Universidad de la República Oriental del Uruguay Montevideo Uruguay; Facultad de Ciencias Laboratorio de Interacciones Moleculares Universidad de la República Oriental del Uruguay Montevideo Uruguay
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33
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Møller RS, Larsen LHG, Johannesen KM, Talvik I, Talvik T, Vaher U, Miranda MJ, Farooq M, Nielsen JEK, Svendsen LL, Kjelgaard DB, Linnet KM, Hao Q, Uldall P, Frangu M, Tommerup N, Baig SM, Abdullah U, Born AP, Gellert P, Nikanorova M, Olofsson K, Jepsen B, Marjanovic D, Al-Zehhawi LIK, Peñalva SJ, Krag-Olsen B, Brusgaard K, Hjalgrim H, Rubboli G, Pal DK, Dahl HA. Gene Panel Testing in Epileptic Encephalopathies and Familial Epilepsies. Mol Syndromol 2016; 7:210-219. [PMID: 27781031 DOI: 10.1159/000448369] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
In recent years, several genes have been causally associated with epilepsy. However, making a genetic diagnosis in a patient can still be difficult, since extensive phenotypic and genetic heterogeneity has been observed in many monogenic epilepsies. This study aimed to analyze the genetic basis of a wide spectrum of epilepsies with age of onset spanning from the neonatal period to adulthood. A gene panel targeting 46 epilepsy genes was used on a cohort of 216 patients consecutively referred for panel testing. The patients had a range of different epilepsies from benign neonatal seizures to epileptic encephalopathies (EEs). Potentially causative variants were evaluated by literature and database searches, submitted to bioinformatic prediction algorithms, and validated by Sanger sequencing. If possible, parents were included for segregation analysis. We identified a presumed disease-causing variant in 49 (23%) of the 216 patients. The variants were found in 19 different genes including SCN1A, STXBP1, CDKL5, SCN2A, SCN8A, GABRA1, KCNA2, and STX1B. Patients with neonatal-onset epilepsies had the highest rate of positive findings (57%). The overall yield for patients with EEs was 32%, compared to 17% among patients with generalized epilepsies and 16% in patients with focal or multifocal epilepsies. By the use of a gene panel consisting of 46 epilepsy genes, we were able to find a disease-causing genetic variation in 23% of the analyzed patients. The highest yield was found among patients with neonatal-onset epilepsies and EEs.
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Affiliation(s)
- Rikke S Møller
- Danish Epilepsy Centre, University of Southern Denmark, Denmark; Institute for Regional Health Services, University of Southern Denmark, Denmark
| | | | - Katrine M Johannesen
- Danish Epilepsy Centre, University of Southern Denmark, Denmark; Institute for Regional Health Services, University of Southern Denmark, Denmark
| | - Inga Talvik
- Tallinn Children's Hospital, Tallinn, Estonia; Tartu University Hospital, Children's Clinic, Tartu, Estonia
| | - Tiina Talvik
- Tartu University Hospital, Children's Clinic, Tartu, Estonia; Department of Paediatrics, University of Tartu, Tartu, Estonia
| | - Ulvi Vaher
- Tartu University Hospital, Children's Clinic, Tartu, Estonia; Department of Paediatrics, University of Tartu, Tartu, Estonia
| | - Maria J Miranda
- Department of Pediatrics, Pediatric Neurology, Herlev University Hospital, Copenhagen University, Herlev, Denmark
| | - Muhammad Farooq
- Department of Cellular and Molecular Medicine, Wilhelm Johannsen Centre for Functional Genome Research, University of Copenhagen, Copenhagen, Denmark; Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE)-PIEAS, Faisalabad, Pakistan
| | - Jens E K Nielsen
- Department of Clinical Medicine, Section of Gynaecology, Obstetrics and Paediatrics, Roskilde Hospital, Roskilde, Denmark
| | | | | | - Karen M Linnet
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
| | - Qin Hao
- Amplexa Genetics, Odense, Denmark
| | - Peter Uldall
- Danish Epilepsy Centre, University of Southern Denmark, Denmark
| | - Mimoza Frangu
- Department of Pediatrics, Holbæk Hospital, Holbæk, Denmark
| | - Niels Tommerup
- Department of Cellular and Molecular Medicine, Wilhelm Johannsen Centre for Functional Genome Research, University of Copenhagen, Copenhagen, Denmark
| | - Shahid M Baig
- Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE)-PIEAS, Faisalabad, Pakistan
| | - Uzma Abdullah
- Department of Cellular and Molecular Medicine, Wilhelm Johannsen Centre for Functional Genome Research, University of Copenhagen, Copenhagen, Denmark; Human Molecular Genetics Laboratory, Health Biotechnology Division, National Institute for Biotechnology and Genetic Engineering (NIBGE)-PIEAS, Faisalabad, Pakistan
| | - Alfred P Born
- Department of Paediatrics, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
| | - Pia Gellert
- Danish Epilepsy Centre, University of Southern Denmark, Denmark
| | - Marina Nikanorova
- Danish Epilepsy Centre, University of Southern Denmark, Denmark; Institute for Regional Health Services, University of Southern Denmark, Denmark
| | - Kern Olofsson
- Danish Epilepsy Centre, University of Southern Denmark, Denmark
| | - Birgit Jepsen
- Danish Epilepsy Centre, University of Southern Denmark, Denmark
| | | | - Lana I K Al-Zehhawi
- Department of Clinical Genetics, Aarhus University Hospital, Aarhus, Denmark
| | | | - Bente Krag-Olsen
- Department of Pediatrics, Aarhus University Hospital, Aarhus, Denmark
| | | | - Helle Hjalgrim
- Danish Epilepsy Centre, University of Southern Denmark, Denmark; Institute for Regional Health Services, University of Southern Denmark, Denmark
| | - Guido Rubboli
- Danish Epilepsy Centre, Filadelfia, Dianalund, Denmark
| | - Deb K Pal
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK
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Fehr S, Downs J, Ho G, de Klerk N, Forbes D, Christodoulou J, Williams S, Leonard H. Functional abilities in children and adults with the CDKL5 disorder. Am J Med Genet A 2016; 170:2860-2869. [DOI: 10.1002/ajmg.a.37851] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 06/17/2016] [Indexed: 01/04/2023]
Affiliation(s)
- Stephanie Fehr
- Telethon Kids Institute; The University of Western Australia; Perth Western Australia Australia
| | - Jenny Downs
- Telethon Kids Institute; The University of Western Australia; Perth Western Australia Australia
- School of Physiotherapy and Exercise Science; Curtin University; Perth Western Australia Australia
| | - Gladys Ho
- Western Sydney Genetics Program; Children's Hospital at Westmead; Sydney New South Wales Australia
- Discipline of Paediatrics and Child Health; University of Sydney; Sydney New South Wales Australia
| | - Nick de Klerk
- Telethon Kids Institute; The University of Western Australia; Perth Western Australia Australia
| | - David Forbes
- School of Paediatrics and Child Health; The University of Western Australia; Perth Western Australia Australia
| | - John Christodoulou
- School of Paediatrics and Child Health; The University of Western Australia; Perth Western Australia Australia
| | - Simon Williams
- Department of Neurology and Rehabilitation; Princess Margaret Hospital; Perth Western Australia Australia
| | - Helen Leonard
- Telethon Kids Institute; The University of Western Australia; Perth Western Australia Australia
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35
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Ream MA, Patel AD. Obtaining genetic testing in pediatric epilepsy. Epilepsia 2015; 56:1505-14. [DOI: 10.1111/epi.13122] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/22/2015] [Indexed: 12/11/2022]
Affiliation(s)
- Margie A. Ream
- Nationwide Children's Hospital; Columbus Ohio U.S.A
- The Ohio State University College of Medicine; Columbus Ohio U.S.A
| | - Anup D. Patel
- Nationwide Children's Hospital; Columbus Ohio U.S.A
- The Ohio State University College of Medicine; Columbus Ohio U.S.A
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36
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Moey C, Topper S, Karn M, Johnson AK, Das S, Vidaurre J, Shoubridge C. Reinitiation of mRNA translation in a patient with X-linked infantile spasms with a protein-truncating variant in ARX. Eur J Hum Genet 2015; 24:681-9. [PMID: 26306640 DOI: 10.1038/ejhg.2015.176] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2015] [Revised: 06/30/2015] [Accepted: 07/03/2015] [Indexed: 12/30/2022] Open
Abstract
Mutations in the Aristaless-related homeobox gene (ARX) lead to a range of X-linked intellectual disability phenotypes, with truncating variants generally resulting in severe X-linked lissencephaly with ambiguous genitalia (XLAG), and polyalanine expansions and missense variants resulting in infantile spasms. We report two male patients with early-onset infantile spasms in whom a novel c.34G>T (p.(E12*)) variant was identified in the ARX gene. A similar variant c.81C>G (p.(Y27*)), has previously been described in two affected cousins with early-onset infantile spasms, leading to reinitiation of ARX mRNA translation resulting in an N-terminal truncated protein. We show that the novel c.34G>T (p.(E12*)) variant also reinitiated mRNA translation at the next AUG codon (c.121-123 (p.M41)), producing the same N-terminally truncated protein. The production of both of these truncated proteins was demonstrated to be at markedly reduced levels using in vitro cell assays. Using luciferase reporter assays, we demonstrate that transcriptional repression capacity of ARX was diminished by both the loss of the N-terminal corepressor octapeptide domain, as a consequence of truncation, and the marked reduction in mutant protein expression. Our study indicates that premature termination mutations very early in ARX lead to reinitiation of translation to produce N-terminally truncated protein at markedly reduced levels of expression. We conclude that even low levels of N-terminally truncated ARX is sufficient to improve the patient's phenotype compared with the severe phenotype of XLAG that includes malformations of the brain and genitalia normally seen in complete loss-of-function mutations in ARX.
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Affiliation(s)
- Ching Moey
- Department of Paediatrics, School of Peadiatrics and Reproductive Health, University of Adelaide, Adelaide, SA, Australia.,Robinson Research Institute, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
| | - Scott Topper
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Mary Karn
- Nationwide Children's Hospital, Columbus, OH, USA
| | | | - Soma Das
- Department of Human Genetics, University of Chicago, Chicago, IL, USA
| | - Jorge Vidaurre
- Nationwide Children's Hospital, The Ohio State University, Columbus, OH, USA
| | - Cheryl Shoubridge
- Department of Paediatrics, School of Peadiatrics and Reproductive Health, University of Adelaide, Adelaide, SA, Australia.,Robinson Research Institute, Faculty of Health Sciences, University of Adelaide, Adelaide, SA, Australia
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37
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Berg AT, Dobyns WB. Progress in autism and related disorders of brain development. Lancet Neurol 2015; 14:1069-70. [PMID: 25891008 DOI: 10.1016/s1474-4422(15)00048-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 04/10/2015] [Indexed: 11/30/2022]
Affiliation(s)
- Anne T Berg
- Lurie Children's Hospital, Epilepsy Center, Chicago, IL 60611, USA.
| | - William B Dobyns
- Department of Pediatrics and Department of Neurology, University of Washington, Seattle, WA 98145, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98145, USA
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38
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Marques I, Sá MJ, Soares G, Mota MDC, Pinheiro C, Aguiar L, Amado M, Soares C, Calado A, Dias P, Sousa AB, Fortuna AM, Santos R, Howell KB, Ryan MM, Leventer RJ, Sachdev R, Catford R, Friend K, Mattiske TR, Shoubridge C, Jorge P. Unraveling the pathogenesis of ARX polyalanine tract variants using a clinical and molecular interfacing approach. Mol Genet Genomic Med 2015; 3:203-14. [PMID: 26029707 PMCID: PMC4444162 DOI: 10.1002/mgg3.133] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Revised: 01/13/2015] [Accepted: 01/15/2015] [Indexed: 12/22/2022] Open
Abstract
The Aristaless-related homeobox (ARX) gene is implicated in intellectual disability with the most frequent pathogenic mutations leading to expansions of the first two polyalanine tracts. Here, we describe analysis of the ARX gene outlining the approaches in the Australian and Portuguese setting, using an integrated clinical and molecular strategy. We report variants in the ARX gene detected in 19 patients belonging to 17 families. Seven pathogenic variants, being expansion mutations in both polyalanine tract 1 and tract 2, were identifyed, including a novel mutation in polyalanine tract 1 that expands the first tract to 20 alanines. This precise number of alanines is sufficient to cause pathogenicity when expanded in polyalanine tract 2. Five cases presented a probably non-pathogenic variant, including the novel HGVS: c.441_455del, classified as unlikely disease causing, consistent with reports that suggest that in frame deletions in polyalanine stretches of ARX rarely cause intellectual disability. In addition, we identified five cases with a variant of unclear pathogenic significance. Owing to the inconsistent ARX variants description, publications were reviewed and ARX variant classifications were standardized and detailed unambiguously according to recommendations of the Human Genome Variation Society. In the absence of a pathognomonic clinical feature, we propose that molecular analysis of the ARX gene should be included in routine diagnostic practice in individuals with either nonsyndromic or syndromic intellectual disability. A definitive diagnosis of ARX-related disorders is crucial for an adequate clinical follow-up and accurate genetic counseling of at-risk family members.
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Affiliation(s)
- Isabel Marques
- Unidade de Genética Molecular, Centro de Genética Médica Doutor Jacinto Magalhães, Centro Hospitalar do Porto, EPE Porto, Portugal ; Unit for Multidisciplinary Research in Biomedicine, UMIB, ICBAS-UP Porto, Portugal
| | - Maria João Sá
- Unidade de Genética Médica, Centro de Genética Médica Doutor Jacinto Magalhães, Centro Hospitalar do Porto, EPE Porto, Portugal ; Unit for Multidisciplinary Research in Biomedicine, UMIB, ICBAS-UP Porto, Portugal
| | - Gabriela Soares
- Unidade de Genética Médica, Centro de Genética Médica Doutor Jacinto Magalhães, Centro Hospitalar do Porto, EPE Porto, Portugal
| | - Maria do Céu Mota
- Department of Pediatrics, Centro Hospitalar do Porto, EPE Porto, Portugal
| | - Carla Pinheiro
- Department of Pediatrics, Hospital Santa Maria Maior, EPE Barcelos, Portugal
| | - Lisa Aguiar
- Department of Pediatrics, Hospital Distrital de Santarém, EPE Santarém, Portugal
| | - Marta Amado
- Department of Pediatrics, Unidade Hospitalar de Portimão, Centro Hospitalar do Algarve Portimão, Portugal
| | - Christina Soares
- Department of Pediatrics, Unidade Hospitalar de Portimão, Centro Hospitalar do Algarve Portimão, Portugal
| | - Angelina Calado
- Department of Pediatrics, Unidade Hospitalar de Portimão, Centro Hospitalar do Algarve Portimão, Portugal
| | - Patrícia Dias
- Department of Genetics, Hospital de Santa Maria Lisboa, Portugal
| | - Ana Berta Sousa
- Department of Genetics, Hospital de Santa Maria Lisboa, Portugal
| | - Ana Maria Fortuna
- Unidade de Genética Médica, Centro de Genética Médica Doutor Jacinto Magalhães, Centro Hospitalar do Porto, EPE Porto, Portugal ; Unit for Multidisciplinary Research in Biomedicine, UMIB, ICBAS-UP Porto, Portugal
| | - Rosário Santos
- Unidade de Genética Molecular, Centro de Genética Médica Doutor Jacinto Magalhães, Centro Hospitalar do Porto, EPE Porto, Portugal ; Unit for Multidisciplinary Research in Biomedicine, UMIB, ICBAS-UP Porto, Portugal
| | - Katherine B Howell
- Department of Neurology, Royal Children's Hospital Melbourne, Victoria, Australia ; Murdoch Childrens Research Institute Melbourne, Victoria, Australia, 3052 ; University of Melbourne Department of Paediatrics Melbourne, Victoria, Australia, 3052
| | - Monique M Ryan
- Department of Neurology, Royal Children's Hospital Melbourne, Victoria, Australia ; Murdoch Childrens Research Institute Melbourne, Victoria, Australia, 3052 ; University of Melbourne Department of Paediatrics Melbourne, Victoria, Australia, 3052
| | - Richard J Leventer
- Department of Neurology, Royal Children's Hospital Melbourne, Victoria, Australia ; Murdoch Childrens Research Institute Melbourne, Victoria, Australia, 3052 ; University of Melbourne Department of Paediatrics Melbourne, Victoria, Australia, 3052
| | - Rani Sachdev
- Department of Medical Genetics, Sydney Children's Hospital High St., Randwick, New South Wales, 2031, Australia
| | - Rachael Catford
- SA Pathology at the Women's and Children's Hospital North Adelaide, South Australia, Australia
| | - Kathryn Friend
- SA Pathology at the Women's and Children's Hospital North Adelaide, South Australia, Australia
| | - Tessa R Mattiske
- Department of Paediatrics, University of Adelaide Adelaide, South Australia, 5006, Australia ; Robinson Research Institute, University of Adelaide Adelaide, South Australia, 5006, Australia
| | - Cheryl Shoubridge
- Department of Paediatrics, University of Adelaide Adelaide, South Australia, 5006, Australia ; Robinson Research Institute, University of Adelaide Adelaide, South Australia, 5006, Australia
| | - Paula Jorge
- Unidade de Genética Molecular, Centro de Genética Médica Doutor Jacinto Magalhães, Centro Hospitalar do Porto, EPE Porto, Portugal ; Unit for Multidisciplinary Research in Biomedicine, UMIB, ICBAS-UP Porto, Portugal
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Fehr S, Leonard H, Ho G, Williams S, de Klerk N, Forbes D, Christodoulou J, Downs J. There is variability in the attainment of developmental milestones in the CDKL5 disorder. J Neurodev Disord 2015; 7:2. [PMID: 25657822 PMCID: PMC4318547 DOI: 10.1186/1866-1955-7-2] [Citation(s) in RCA: 58] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Accepted: 12/16/2014] [Indexed: 11/29/2022] Open
Abstract
Background Individuals with the CDKL5 disorder have been described as having severely impaired development. A few individuals have been reported having attained more milestones including walking and running. Our aim was to investigate variation in attainment of developmental milestones and associations with underlying genotype. Methods Data was sourced from the International CDKL5 Disorder Database, and individuals were included if they had a pathogenic or probably pathogenic CDKL5 mutation and information on early development. Kaplan-Meier time-to-event analyses investigated the occurrence of developmental milestones. Mutations were grouped by their structural/functional consequence, and Cox regression was used to investigate the relationship between genotype and milestone attainment. Results The study included 109 females and 18 males. By 5 years of age, only 75% of the females had attained independent sitting and 25% independent walking whilst a quarter of the males could sit independently by 1 year 3 months. Only one boy could walk independently. No clear relationship between mutation group and milestone attainment was present, although females with a late truncating mutation attained the most milestones. Conclusion Attainment of developmental milestones is severely impaired in the CDKL5 disorder, with the majority who did attain skills attaining them at a late age. It appears as though males are more severely impaired than the females. Larger studies are needed to further investigate the role of genotype on clinical variability.
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Affiliation(s)
- Stephanie Fehr
- Telethon Kids Institute, University of Western Australia, Perth, Western Australia Australia
| | - Helen Leonard
- Telethon Kids Institute, University of Western Australia, Perth, Western Australia Australia
| | - Gladys Ho
- Western Sydney Genetics Program, Children's Hospital at Westmead, Sydney, NSW Australia
| | - Simon Williams
- Department of Neurology and Rehabilitation, Princess Margaret Hospital, Perth, Western Australia Australia
| | - Nick de Klerk
- Telethon Kids Institute, University of Western Australia, Perth, Western Australia Australia
| | - David Forbes
- School of Paediatrics and Child Health, University of Western Australia, Perth, Western Australia Australia
| | - John Christodoulou
- Western Sydney Genetics Program, Children's Hospital at Westmead, Sydney, NSW Australia ; Disciplines of Paediatrics & Child Health and Genetic Medicine, University of Sydney, Sydney, NSW Australia
| | - Jenny Downs
- Telethon Kids Institute, University of Western Australia, Perth, Western Australia Australia ; School of Physiotherapy and Exercise Science, Curtin University, Perth, Western Australia Australia
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Szafranski P, Golla S, Jin W, Fang P, Hixson P, Matalon R, Kinney D, Bock HG, Craigen W, Smith JL, Bi W, Patel A, Wai Cheung S, Bacino CA, Stankiewicz P. Neurodevelopmental and neurobehavioral characteristics in males and females with CDKL5 duplications. Eur J Hum Genet 2014; 23:915-21. [PMID: 25315662 DOI: 10.1038/ejhg.2014.217] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 08/21/2014] [Accepted: 09/05/2014] [Indexed: 12/21/2022] Open
Abstract
Point mutations and genomic deletions of the CDKL5 (STK9) gene on chromosome Xp22 have been reported in patients with severe neurodevelopmental abnormalities, including Rett-like disorders. To date, only larger-sized (8-21 Mb) duplications harboring CDKL5 have been described. We report seven females and four males from seven unrelated families with CDKL5 duplications 540-935 kb in size. Three families of different ethnicities had identical 667kb duplications containing only the shorter CDKL5 isoform. Four affected boys, 8-14 years of age, and three affected girls, 6-8 years of age, manifested autistic behavior, developmental delay, language impairment, and hyperactivity. Of note, two boys and one girl had macrocephaly. Two carrier mothers of the affected boys reported a history of problems with learning and mathematics while at school. None of the patients had epilepsy. Similarly to CDKL5 mutations and deletions, the X-inactivation pattern in all six studied females was random. We hypothesize that the increased dosage of CDKL5 might have affected interactions of this kinase with its substrates, leading to perturbation of synaptic plasticity and learning, and resulting in autistic behavior, developmental and speech delay, hyperactivity, and macrocephaly.
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Affiliation(s)
- Przemyslaw Szafranski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Sailaja Golla
- Departments of Pediatrics and Neurology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Weihong Jin
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Ping Fang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Patricia Hixson
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Reuben Matalon
- Division of General Academic Pediatrics, Department of Pediatrics, The University of Texas Medical Branch at Galveston, Galveston, TX, USA
| | - Daniel Kinney
- Memorial Children's Hospital Navarre Pediatrics South Bend, South Bend, IN, USA
| | - Hans-Georg Bock
- Department of Pediatrics, University of Mississippi Medical Center, Jackson, MS, USA
| | - William Craigen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Janice L Smith
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Weimin Bi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Ankita Patel
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Sau Wai Cheung
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Carlos A Bacino
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Paweł Stankiewicz
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
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Mei D, Darra F, Barba C, Marini C, Fontana E, Chiti L, Parrini E, Dalla Bernardina B, Guerrini R. Optimizing the molecular diagnosis ofCDKL5gene-related epileptic encephalopathy in boys. Epilepsia 2014; 55:1748-53. [DOI: 10.1111/epi.12803] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2014] [Indexed: 01/15/2023]
Affiliation(s)
- Davide Mei
- Pediatric Neurology and Neurogenetics Unit and Laboratories; A. Meyer Children's Hospital-University of Florence; Florence Italy
| | - Francesca Darra
- Department of Life and Reproduction Sciences-Section of Child Neurology and Psychiatry; University of Verona; Verona Italy
| | - Carmen Barba
- Pediatric Neurology and Neurogenetics Unit and Laboratories; A. Meyer Children's Hospital-University of Florence; Florence Italy
| | - Carla Marini
- Pediatric Neurology and Neurogenetics Unit and Laboratories; A. Meyer Children's Hospital-University of Florence; Florence Italy
| | - Elena Fontana
- Department of Life and Reproduction Sciences-Section of Child Neurology and Psychiatry; University of Verona; Verona Italy
| | - Laura Chiti
- Pediatric Neurology and Neurogenetics Unit and Laboratories; A. Meyer Children's Hospital-University of Florence; Florence Italy
| | - Elena Parrini
- Pediatric Neurology and Neurogenetics Unit and Laboratories; A. Meyer Children's Hospital-University of Florence; Florence Italy
| | - Bernardo Dalla Bernardina
- Department of Life and Reproduction Sciences-Section of Child Neurology and Psychiatry; University of Verona; Verona Italy
| | - Renzo Guerrini
- Pediatric Neurology and Neurogenetics Unit and Laboratories; A. Meyer Children's Hospital-University of Florence; Florence Italy
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Seltzer LE, Paciorkowski AR. Genetic disorders associated with postnatal microcephaly. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2014; 166C:140-55. [PMID: 24839169 DOI: 10.1002/ajmg.c.31400] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Several genetic disorders are characterized by normal head size at birth, followed by deceleration in head growth resulting in postnatal microcephaly. Among these are classic disorders such as Angelman syndrome and MECP2-related disorder (formerly Rett syndrome), as well as more recently described clinical entities associated with mutations in CASK, CDKL5, CREBBP, and EP300 (Rubinstein-Taybi syndrome), FOXG1, SLC9A6 (Christianson syndrome), and TCF4 (Pitt-Hopkins syndrome). These disorders can be identified clinically by phenotyping across multiple neurodevelopmental and neurobehavioral realms, and enough data are available to recognize these postnatal microcephaly disorders as separate diagnostic entities in their own right. A second diagnostic grouping, comprised of Warburg MICRO syndrome, Cockayne syndrome, and Cerebral-oculo-facial skeletal syndrome, share similar features of somatic growth failure, ophthalmologic, and dysmorphologic features. Many postnatal microcephaly syndromes are caused by mutations in genes important in the regulation of gene expression in the developing forebrain and hindbrain, although important synaptic structural genes also play a role. This is an emerging group of disorders with a fascinating combination of brain malformations, specific epilepsies, movement disorders, and other complex neurobehavioral abnormalities.
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43
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Michaud JL, Lachance M, Hamdan FF, Carmant L, Lortie A, Diadori P, Major P, Meijer IA, Lemyre E, Cossette P, Mefford HC, Rouleau GA, Rossignol E. The genetic landscape of infantile spasms. Hum Mol Genet 2014; 23:4846-58. [PMID: 24781210 DOI: 10.1093/hmg/ddu199] [Citation(s) in RCA: 136] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Infantile spasms (IS) is an early-onset epileptic encephalopathy of unknown etiology in ∼40% of patients. We hypothesized that unexplained IS cases represent a large collection of rare single-gene disorders. We investigated 44 children with unexplained IS using comparative genomic hybridisation arrays (aCGH) (n = 44) followed by targeted sequencing of 35 known epilepsy genes (n = 8) or whole-exome sequencing (WES) of familial trios (n = 18) to search for rare inherited or de novo mutations. aCGH analysis revealed de novo variants in 7% of patients (n = 3/44), including a distal 16p11.2 duplication, a 15q11.1q13.1 tetrasomy and a 2q21.3-q22.2 deletion. Furthermore, it identified a pathogenic maternally inherited Xp11.2 duplication. Targeted sequencing was informative for ARX (n = 1/14) and STXBP1 (n = 1/8). In contrast, sequencing of a panel of 35 known epileptic encephalopathy genes (n = 8) did not identify further mutations. Finally, WES (n = 18) was very informative, with an excess of de novo mutations identified in genes predicted to be involved in neurodevelopmental processes and/or known to be intolerant to functional variations. Several pathogenic mutations were identified, including de novo mutations in STXBP1, CASK and ALG13, as well as recessive mutations in PNPO and ADSL, together explaining 28% of cases (5/18). In addition, WES identified 1-3 de novo variants in 64% of remaining probands, pointing to several interesting candidate genes. Our results indicate that IS are genetically heterogeneous with a major contribution of de novo mutations and that WES is significantly superior to targeted re-sequencing in identifying detrimental genetic variants involved in IS.
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Affiliation(s)
- Jacques L Michaud
- Department of Pediatrics and Department of Neurosciences, Université de Montréal, Montréal, QC, Canada, CHU Ste-Justine Research Center, Montréal, QC, Canada
| | | | - Fadi F Hamdan
- CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - Lionel Carmant
- Department of Pediatrics and Department of Neurosciences, Université de Montréal, Montréal, QC, Canada, CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - Anne Lortie
- Department of Pediatrics and Department of Neurosciences, Université de Montréal, Montréal, QC, Canada, CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - Paola Diadori
- Department of Pediatrics and Department of Neurosciences, Université de Montréal, Montréal, QC, Canada, CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - Philippe Major
- Department of Pediatrics and Department of Neurosciences, Université de Montréal, Montréal, QC, Canada, CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - Inge A Meijer
- CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - Emmanuelle Lemyre
- Department of Pediatrics and CHU Ste-Justine Research Center, Montréal, QC, Canada
| | - Patrick Cossette
- Department of Neurosciences, Université de Montréal, Montréal, QC, Canada, CHUM, Montréal, QC, Canada
| | - Heather C Mefford
- Department of Pediatrics, University of Washington, Seattle, WA, USA and
| | - Guy A Rouleau
- Department of Neurosciences, Montreal Neurological Institute, McGill University, Montréal, QC, Canada
| | - Elsa Rossignol
- Department of Pediatrics and Department of Neurosciences, Université de Montréal, Montréal, QC, Canada, CHU Ste-Justine Research Center, Montréal, QC, Canada,
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