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Kharrat M, Triki CC, Alila-Fersi O, Jallouli O, Khemakham B, Mallouli S, Maalej M, Ammar M, Frikha F, Kamoun F, Fakhfakh F. Combined in Silico Prediction Methods, Molecular Dynamic Simulation, and Molecular Docking of FOXG1 Missense Mutations: Effect on FoxG1 Structure and Its Interactions with DNA and Bmi-1 Protein. J Mol Neurosci 2022; 72:1695-1705. [PMID: 35654936 DOI: 10.1007/s12031-022-02032-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 05/23/2022] [Indexed: 11/28/2022]
Abstract
FoxG1 encoded by FOXG1 gene is a transcriptional factor interacting with the DNA of targeted genes as well as with several proteins to regulate the forebrain development. Mutations in the FOXG1 gene have been shown to cause a wide spectrum of brain disorders, including the congenital variant of Rett syndrome. In this study, the direct sequencing of FOXG1 gene revealed a novel c.645C > A (F215L) variant in the patient P1 and a de novo known one c.755G > A (G252D) in the patient P2. To investigate the putative impact of FOXG1 missense variants, a computational pipeline by the application of in silico prediction methods, molecular dynamic simulation, and molecular docking approaches was used. Bioinformatics analysis and molecular dynamics simulation have demonstrated that F215L and G252D variants found in the DNA binding domain are highly deleterious mutations that may cause the protein structure destabilization. On the other hand, molecular docking revealed that F215L mutant is likely to have a great impact on destabilizing the protein structure and the disruption of the Bmi-1 binding site quite significantly. Regarding G252D mutation, it seems to abolish the ability of FoxG1 to bind DNA target, affecting the transcriptional regulation of targeted genes. Our study highlights the usefulness of combined computational approaches, molecular dynamic simulation, and molecular docking for a better understanding of the dysfunctional effects of FOXG1 missense mutations and their role in the etiopathogenesis as well as in the genotype-phenotype correlation.
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Affiliation(s)
- Marwa Kharrat
- Laboratory of Molecular and Functional Genetics, Faculty of Science, Sfax University, Sfax, Tunisia.
| | - Chahnez Charfi Triki
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia.,Research Laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Olfa Alila-Fersi
- Laboratory of Molecular and Functional Genetics, Faculty of Science, Sfax University, Sfax, Tunisia
| | - Olfa Jallouli
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia.,Research Laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Bassem Khemakham
- Laboratory of Plant Biotechnology, Faculty of Sciences of Sfax, Sfax University, Sfax, Tunisia
| | - Salma Mallouli
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia.,Research Laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Marwa Maalej
- Laboratory of Molecular and Functional Genetics, Faculty of Science, Sfax University, Sfax, Tunisia
| | - Marwa Ammar
- Laboratory of Molecular and Functional Genetics, Faculty of Science, Sfax University, Sfax, Tunisia
| | - Fakher Frikha
- Laboratory of Molecular and Cellular Screening Processes, Center of Biotechnology of Sfax, University of Sfax, Sfax, Tunisia
| | - Fatma Kamoun
- Child Neurology Department, Hedi Chaker Hospital, Sfax, Tunisia.,Research Laboratory (LR19ES15), Sfax Medical School, Sfax University, Sfax, Tunisia
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Science, Sfax University, Sfax, Tunisia.
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2
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Ni Y, Liu B, Wu X, Liu J, Ba R, Zhao C. FOXG1 Directly Suppresses Wnt5a During the Development of the Hippocampus. Neurosci Bull 2021; 37:298-310. [PMID: 33389683 DOI: 10.1007/s12264-020-00618-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 07/19/2020] [Indexed: 12/17/2022] Open
Abstract
The Wnt signaling pathway plays key roles in various developmental processes. Wnt5a, which activates the non-canonical pathway, has been shown to be particularly important for axon guidance and outgrowth as well as dendrite morphogenesis. However, the mechanism underlying the regulation of Wnt5a remains unclear. Here, through conditional disruption of Foxg1 in hippocampal progenitors and postmitotic neurons achieved by crossing Foxg1fl/fl with Emx1-Cre and Nex-Cre, respectively, we found that Wnt5a rather than Wnt3a/Wnt2b was markedly upregulated. Overexpression of Foxg1 had the opposite effects along with decreased dendritic complexity and reduced mossy fibers in the hippocampus. We further demonstrated that FOXG1 directly repressed Wnt5a by binding to its promoter and one enhancer site. These results expand our knowledge of the interaction between Foxg1 and Wnt signaling and help elucidate the mechanisms underlying hippocampal development.
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Affiliation(s)
- Yang Ni
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, 210009, China
| | - Bin Liu
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, 210009, China
| | - Xiaojing Wu
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, 210009, China
| | - Junhua Liu
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, 210009, China
| | - Ru Ba
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, 210009, China
| | - Chunjie Zhao
- Key Laboratory of Developmental Genes and Human Diseases, Ministry of Education, School of Medicine, Southeast University, Nanjing, 210009, China.
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3
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Abstract
Rett syndrome (RTT) is a severe progressive neurodevelopmental disease characterized by psychomotor regression. The FOXG1 gene is one of the pathogenic genes associated with the congenital Rett variant, which is less studied. Only a few Chinese patients with FOXG1 mutation have been reported. In this study, we describe a Chinese female patient with congenital Rett variant who presented with psycho-motor retardation, developmental regression, microcephaly, seizure, stereotypic hand movement and hypotonia. Targeted high-throughput sequencing was conducted, and a heterozygous FOXG1 mutation [NM_005249.4: c.506dupG (P.G169Gfs* 286)] was identified. It was a frameshift mutation resulting in alteration of the reading frames downstream of the mutation. SIMILAR CASES PUBLISHED: 10. CONFLICT OF INTEREST: None.
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Affiliation(s)
- Yan Niu
- From the Department of Rehabilitation, Tianjin Children's Hospital, Tianjin, China
| | - Lirong Cao
- From the Graduate College, Tianjin Medical University, Tianjin, China
| | - Peng Zhao
- From the Department of Rehabilitation, Tianjin Children's Hospital, Tianjin, China
| | - Chunguan Cai
- From the Department of Neurosurgery, Tianjin Children's Hospital, Tianjin, China
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4
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Hou PS, hAilín DÓ, Vogel T, Hanashima C. Transcription and Beyond: Delineating FOXG1 Function in Cortical Development and Disorders. Front Cell Neurosci 2020; 14:35. [PMID: 32158381 PMCID: PMC7052011 DOI: 10.3389/fncel.2020.00035] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Accepted: 02/04/2020] [Indexed: 11/13/2022] Open
Abstract
Forkhead Box G1 (FOXG1) is a member of the Forkhead family of genes with non-redundant roles in brain development, where alteration of this gene's expression significantly affects the formation and function of the mammalian cerebral cortex. FOXG1 haploinsufficiency in humans is associated with prominent differences in brain size and impaired intellectual development noticeable in early childhood, while homozygous mutations are typically fatal. As such, FOXG1 has been implicated in a wide spectrum of congenital brain disorders, including the congenital variant of Rett syndrome, infantile spasms, microcephaly, autism spectrum disorder (ASD) and schizophrenia. Recent technological advances have yielded greater insight into phenotypic variations observed in FOXG1 syndrome, molecular mechanisms underlying pathogenesis of the disease, and multifaceted roles of FOXG1 expression. In this review, we explore the emerging mechanisms of FOXG1 in a range of transcriptional to posttranscriptional events in order to evolve our current view of how a single transcription factor governs the assembly of an elaborate cortical circuit responsible for higher cognitive functions and neurological disorders.
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Affiliation(s)
- Pei-Shan Hou
- Laboratory for Developmental Biology, Department of Biology, Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, Japan.,Institute of Anatomy and Cell Biology, School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Darren Ó hAilín
- Department of Molecular Embryology, Institute of Anatomy and Cell Biology, Medical Faculty, University of Freiburg, Freiburg, Germany
| | - Tanja Vogel
- Department of Molecular Embryology, Institute of Anatomy and Cell Biology, Medical Faculty, University of Freiburg, Freiburg, Germany.,Center for Basics in NeuroModulation (NeuroModul Basics), Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Carina Hanashima
- Laboratory for Developmental Biology, Department of Biology, Faculty of Education and Integrated Arts and Sciences, Waseda University, Tokyo, Japan.,Department of Integrative Bioscience and Biomedical Engineering, Graduate School of Advanced Science and Engineering, Waseda University Center for Advanced Biomedical Sciences, Tokyo, Japan
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5
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Mild presentation of the congenital variant Rett syndrome in a Pakistani male: expanding the phenotype of the forkhead box protein G1 spectrum. Clin Dysmorphol 2019; 29:111-113. [PMID: 31577544 DOI: 10.1097/mcd.0000000000000302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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6
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FOXG1-Related Syndrome: From Clinical to Molecular Genetics and Pathogenic Mechanisms. Int J Mol Sci 2019; 20:ijms20174176. [PMID: 31454984 PMCID: PMC6747066 DOI: 10.3390/ijms20174176] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 08/23/2019] [Accepted: 08/25/2019] [Indexed: 12/29/2022] Open
Abstract
Individuals with mutations in forkhead box G1 (FOXG1) belong to a distinct clinical entity, termed “FOXG1-related encephalopathy”. There are two clinical phenotypes/syndromes identified in FOXG1-related encephalopathy, duplications and deletions/intragenic mutations. In children with deletions or intragenic mutations of FOXG1, the recognized clinical features include microcephaly, developmental delay, severe cognitive disabilities, early-onset dyskinesia and hyperkinetic movements, stereotypies, epilepsy, and cerebral malformation. In contrast, children with duplications of FOXG1 are typically normocephalic and have normal brain magnetic resonance imaging. They also have different clinical characteristics in terms of epilepsy, movement disorders, and neurodevelopment compared with children with deletions or intragenic mutations. FOXG1 is a transcriptional factor. It is expressed mainly in the telencephalon and plays a pleiotropic role in the development of the brain. It is a key player in development and territorial specification of the anterior brain. In addition, it maintains the expansion of the neural proliferating pool, and also regulates the pace of neocortical neuronogenic progression. It also facilitates cortical layer and corpus callosum formation. Furthermore, it promotes dendrite elongation and maintains neural plasticity, including dendritic arborization and spine densities in mature neurons. In this review, we summarize the clinical features, molecular genetics, and possible pathogenesis of FOXG1-related syndrome.
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Yu B, Liu J, Su M, Wang C, Chen H, Zhao C. Disruption of Foxg1 impairs neural plasticity leading to social and cognitive behavioral defects. Mol Brain 2019; 12:63. [PMID: 31253171 PMCID: PMC6599246 DOI: 10.1186/s13041-019-0484-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 06/20/2019] [Indexed: 12/14/2022] Open
Abstract
The transcription factor Foxg1 is known to be continuously expressed at a high level in mature neurons in the telencephalon, but little is known about its role in neural plasticity. Mutations in human FOXG1 cause deficiencies in learning and memory and limit social ability, which is defined as FOXG1 syndrome, but its pathogenic mechanism remains unclear. To examine the role of Foxg1 in adults, we crossed Camk2a-CreER with Foxg1fl/fl mice and conditionally disrupted Foxg1 with tamoxifen in mature neurons. We found that spatial learning and memory were significantly impaired when examined by the Morris water maze test. The cKO mice also showed a significant reduction in freezing time during the contextual and cued fear conditioning test, indicating that fear conditioning memory was affected. A remarkable reduction in Schaffer-collateral long-term potentiation was also recorded. Morphologically, the dendritic arborization and spine densities of hippocampal pyramidal neurons were significantly reduced. Primary cell culture further confirmed altered dendritic complexity after Foxg1 deletion. Our results indicated that Foxg1 plays an important role in maintaining the neural plasticity, which is vital to high-grade function.
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Affiliation(s)
- Baocong Yu
- Key Laboratory of Developmental Genes and Human Diseases, MOE, School of Medicine, Southeast University, Nanjing, 210009, China
| | - Junhua Liu
- Key Laboratory of Developmental Genes and Human Diseases, MOE, School of Medicine, Southeast University, Nanjing, 210009, China
| | - Mingzhao Su
- Key Laboratory of Developmental Genes and Human Diseases, MOE, School of Medicine, Southeast University, Nanjing, 210009, China
| | - Chunlian Wang
- Key Lab of Cognition and Personality, MOE, School of Psychology, Southwest University, Chongqing, 400715, China
| | - Huanxin Chen
- Key Lab of Cognition and Personality, MOE, School of Psychology, Southwest University, Chongqing, 400715, China
| | - Chunjie Zhao
- Key Laboratory of Developmental Genes and Human Diseases, MOE, School of Medicine, Southeast University, Nanjing, 210009, China.
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8
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Wong LC, Wu YT, Hsu CJ, Weng WC, Tsai WC, Lee WT. Cognition and Evolution of Movement Disorders of FOXG1-Related Syndrome. Front Neurol 2019; 10:641. [PMID: 31316448 PMCID: PMC6611493 DOI: 10.3389/fneur.2019.00641] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Accepted: 05/30/2019] [Indexed: 12/12/2022] Open
Abstract
FOXG1-related syndrome is a rare neurodevelopmental encephalopathy characterized by early onset hyperkinetic movement disorders, absent language, autistic features, epilepsy, and severe cognitive impairment. However, detailed evaluation of cognition and evolution of movement disorders over time have not been clearly described before. In this study, we performed whole-exome sequencing in a cohort with unknown severe encephalopathy and movement disorders, with/without autistic behaviors. We identified FOXG1 mutations in three patients. One of them had a novel mutation that has not been described before. The neuropsychological test by Mullen Scales of Early Learning (MSEL) showed severe psychomotor impairments in all patients. There were uneven cognitive abilities in terms of verbal and non-verbal cognitive domains in all of them, with approximately 2 months differences. Gross motor skills and expressive language were more severely affected than the other domains in all the patients. All individuals had early onset hyperkinetic movement disorders. The movement disorders in one of our patients changed from predominantly hyperkinetic in early childhood to more hypokinetic in adolescence with the development of dystonia. To the best of our knowledge, this evolution had never been described before. In conclusion, individuals with FOXG1-related syndrome may show clinical progression from hyperkinetic to hypokinetic features over time. There were also uneven cognitive abilities in verbal and non-verbal cognitive domains. The FOXG1 mutation should be considered in individuals with a history of hyperkinetic movements, microcephaly, and uneven cognitive abilities with characteristic brain images.
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Affiliation(s)
- Lee-Chin Wong
- Department of Pediatrics, Cathay General Hospital, Taipei, Taiwan.,Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine, Taipei, Taiwan
| | - Yen-Tzu Wu
- School and Graduate Institute of Physical Therapy, National Taiwan University College of Medicine, Taipei, Taiwan.,Department of Physical Medicine and Rehabilitation, National Taiwan University, Taipei, Taiwan
| | - Chia-Jui Hsu
- Department of Pediatrics, Taipei City Hospital YangMing Branch, Taipei, Taiwan
| | - Wen-Chin Weng
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan
| | - Wen-Che Tsai
- Department of Psychiatry, National Taiwan University Hospital, Taipei, Taiwan
| | - Wang-Tso Lee
- Department of Pediatrics, National Taiwan University Hospital, Taipei, Taiwan.,Graduate Institute of Brain and Mind Sciences, National Taiwan University College of Medicine, Taipei, Taiwan
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9
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Vegas N, Cavallin M, Maillard C, Boddaert N, Toulouse J, Schaefer E, Lerman-Sagie T, Lev D, Magalie B, Moutton S, Haan E, Isidor B, Heron D, Milh M, Rondeau S, Michot C, Valence S, Wagner S, Hully M, Mignot C, Masurel A, Datta A, Odent S, Nizon M, Lazaro L, Vincent M, Cogné B, Guerrot AM, Arpin S, Pedespan JM, Caubel I, Pontier B, Troude B, Rivier F, Philippe C, Bienvenu T, Spitz MA, Bery A, Bahi-Buisson N. Delineating FOXG1 syndrome: From congenital microcephaly to hyperkinetic encephalopathy. NEUROLOGY-GENETICS 2018; 4:e281. [PMID: 30533527 PMCID: PMC6244024 DOI: 10.1212/nxg.0000000000000281] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 07/12/2018] [Indexed: 12/24/2022]
Abstract
Objective To provide new insights into the FOXG1-related clinical and imaging phenotypes and refine the phenotype-genotype correlation in FOXG1 syndrome. Methods We analyzed the clinical and imaging phenotypes of a cohort of 45 patients with a pathogenic or likely pathogenic FOXG1 variant and performed phenotype-genotype correlations. Results A total of 37 FOXG1 different heterozygous mutations were identified, of which 18 are novel. We described a broad spectrum of neurodevelopmental phenotypes, characterized by severe postnatal microcephaly and developmental delay accompanied by a hyperkinetic movement disorder, stereotypes and sleep disorders, and epileptic seizures. Our data highlighted 3 patterns of gyration, including frontal pachygyria in younger patients (26.7%), moderate simplified gyration (24.4%) and mildly simplified or normal gyration (48.9%), corpus callosum hypogenesis mostly in its frontal part, combined with moderate-to-severe myelination delay that improved and normalized with age. Frameshift and nonsense mutations in the N-terminus of FOXG1, which are the most common mutation types, show the most severe clinical features and MRI anomalies. However, patients with recurrent frameshift mutations c.460dupG and c.256dupC had variable clinical and imaging presentations. Conclusions These findings have implications for genetic counseling, providing evidence that N-terminal mutations and large deletions lead to more severe FOXG1 syndrome, although genotype-phenotype correlations are not necessarily straightforward in recurrent mutations. Together, these analyses support the view that FOXG1 syndrome is a specific disorder characterized by frontal pachygyria and delayed myelination in its most severe form and hypogenetic corpus callosum in its milder form.
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10
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Kuster A, Arnoux JB, Barth M, Lamireau D, Houcinat N, Goizet C, Doray B, Gobin S, Schiff M, Cano A, Amsallem D, Barnerias C, Chaumette B, Plaze M, Slama A, Ioos C, Desguerre I, Lebre AS, de Lonlay P, Christa L. Diagnostic approach to neurotransmitter monoamine disorders: experience from clinical, biochemical, and genetic profiles. J Inherit Metab Dis 2018; 41:129-139. [PMID: 28924877 DOI: 10.1007/s10545-017-0079-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 07/10/2017] [Accepted: 07/27/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND AND AIM To improve the diagnostic work-up of patients with diverse neurological diseases, we have elaborated specific clinical and CSF neurotransmitter patterns. METHODS Neurotransmitter determinations in CSF from 1200 patients revealed abnormal values in 228 (19%) cases. In 54/228 (24%) patients, a final diagnosis was identified. RESULTS We have reported primary (30/54, 56%) and secondary (24/54, 44%) monoamine neurotransmitter disorders. For primary deficiencies, the most frequently mutated gene was DDC (n = 9), and the others included PAH with neuropsychiatric features (n = 4), PTS (n = 5), QDPR (n = 3), SR (n = 1), and TH (n = 1). We have also identified mutations in SLC6A3, FOXG1 (n = 1 of each), MTHFR (n = 3), FOLR1, and MTHFD (n = 1 of each), for dopamine transporter, neuronal development, and folate metabolism disorders, respectively. For secondary deficiencies, we have identified POLG (n = 3), ACSF3 (n = 1), NFU1, and SDHD (n = 1 of each), playing a role in mitochondrial function. Other mutated genes included: ADAR, RNASEH2B, RNASET2, SLC7A2-IT1 A/B lncRNA, and EXOSC3 involved in nuclear and cytoplasmic metabolism; RanBP2 and CASK implicated in post-traductional and scaffolding modifications; SLC6A19 regulating amino acid transport; MTM1, KCNQ2 (n = 2), and ATP1A3 playing a role in nerve cell electrophysiological state. Chromosome abnormalities, del(8)(p23)/dup(12) (p23) (n = 1), del(6)(q21) (n = 1), dup(17)(p13.3) (n = 1), and non-genetic etiologies (n = 3) were also identified. CONCLUSION We have classified the final 54 diagnoses in 11 distinctive biochemical profiles and described them through 20 clinical features. To identify the specific molecular cause of abnormal NT profiles, (targeted) genomics might be used, to improve diagnosis and allow early treatment of complex and rare neurological genetic diseases.
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Affiliation(s)
- Alice Kuster
- Neurometabolism department, Nantes Hospital and University, Nantes, France
| | - Jean-Baptiste Arnoux
- Reference center for inherited metabolic diseases, Necker Enfants-Malades Hospital, Assistance Publique Hôpitaux de Paris, Imagine Institute, Paris Descartes University, Paris, France
| | - Magalie Barth
- Neurometabolism department, Angers Hospital and University, Angers, France
| | - Delphine Lamireau
- Neuropediatric and Neurogenetic department, MRGM laboratory, National institute for health and medical research U1211, Pellegrin Hospital and University, Bordeaux, France
| | - Nada Houcinat
- Neuropediatric and Neurogenetic department, MRGM laboratory, National institute for health and medical research U1211, Pellegrin Hospital and University, Bordeaux, France
| | - Cyril Goizet
- Neuropediatric and Neurogenetic department, MRGM laboratory, National institute for health and medical research U1211, Pellegrin Hospital and University, Bordeaux, France
| | - Bérénice Doray
- Genetic department, Félix Guyon Hospital and University, Saint-Denis de la Réunion, France
| | - Stéphanie Gobin
- Genetic department, Necker-Enfants Malades Hospital, Assistance Publique Hôpitaux de Paris, Paris, France
| | - Manuel Schiff
- Neurometabolism and Biochemical department, Robert Debré Hospital and University, Paris, France
| | - Aline Cano
- Reference center for inherited metabolic diseases, la Timone-Marseille Hospital and University, Marseille, France
| | - Daniel Amsallem
- Neuropediatric department, Jean Minjoz Hospital, Besançon, France
| | - Christine Barnerias
- Neurology department, Necker Enfants Malades Hospital and Paris Descartes University, Paris, France
| | - Boris Chaumette
- Sainte Anne Hospital, University Hospital Department (SHU), Paris Descartes University and Institut National de la Santé et de la Recherche Médicale INSERM U894, CNRS GDR, 3557, Paris, France
| | - Marion Plaze
- Sainte Anne Hospital, University Hospital Department (SHU), Paris Descartes University and Institut National de la Santé et de la Recherche Médicale INSERM U894, CNRS GDR, 3557, Paris, France
| | - Abdelhamid Slama
- Biochemical department, Bicêtre Hospital, Assistance Publique Hôpitaux de Paris, Le Kremlin Bicêtre, France
| | - Christine Ioos
- Neuropediatric department, Raymond Poincaré Hospital, Garches, France
| | - Isabelle Desguerre
- Neurology department, Necker Enfants Malades Hospital and Paris Descartes University, Paris, France
| | - Anne-Sophie Lebre
- Genetic and Biological department, Reims University, Maison Blanche Hospital, F-51092, Reims, France
| | - Pascale de Lonlay
- Reference center for inherited metabolic diseases, Necker Enfants-Malades Hospital, Assistance Publique Hôpitaux de Paris, Imagine Institute, Paris Descartes University, Paris, France
| | - Laurence Christa
- Metabolomic and proteomic Biochemical department, Necker Enfants-Malades Hospital, Paris Descartes University, Paris, France.
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Harada K, Yamamoto M, Konishi Y, Koyano K, Takahashi S, Namba M, Kusaka T. Hypoplastic hippocampus in atypical Rett syndrome with a novel FOXG1 mutation. Brain Dev 2018; 40:49-52. [PMID: 28781028 DOI: 10.1016/j.braindev.2017.07.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 06/24/2017] [Accepted: 07/17/2017] [Indexed: 11/28/2022]
Abstract
The forkhead box G1 (FOXG1) gene encodes a brain-specific transcription factor and is associated with a congenital variant of atypical Rett syndrome (RTT); several FOXG1 mutations have been identified. The congenital variant of RTT shows a hypoplastic corpus callosum, delayed myelination, and frontal and temporal atrophy. Although no report has described a hippocampal abnormality in humans, the current study suggests that FOXG1 also regulates neurogenesis in the postnatal hippocampus. In the present case, severe developmental delay was observed in a patient with a congenital variant of RTT from about 4months, in conjunction with acquired microcephaly, hypotonia, limited motor function, absent purposeful hand use, and repetitive jerky movements of the upper limbs. A novel missense mutation was identified in FOXG1 on gene analysis (c. 569T>A, p. Ile190Asn). The patient showed not only the typical cerebral abnormalities of a congenital variant of RTT, but also a hypoplastic hippocampus. This novel mutation and cerebral findings may provide new insights into the pathophysiology of the congenital variant of RTT.
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Affiliation(s)
- Kotoha Harada
- Department of Pediatrics, Shodoshima Central Hospital, Japan.
| | - Mayumi Yamamoto
- Department of Pediatrics, Shodoshima Central Hospital, Japan
| | - Yukihiko Konishi
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Japan
| | - Kaori Koyano
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Japan
| | | | - Masanori Namba
- Department of Pediatrics, Kagawa Rehabilitation Center, Japan
| | - Takashi Kusaka
- Department of Pediatrics, Faculty of Medicine, Kagawa University, Japan
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12
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FOXG1 syndrome: genotype-phenotype association in 83 patients with FOXG1 variants. Genet Med 2017; 20:98-108. [PMID: 28661489 DOI: 10.1038/gim.2017.75] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 03/16/2017] [Indexed: 12/31/2022] Open
Abstract
PurposeThe study aimed at widening the clinical and genetic spectrum and assessing genotype-phenotype associations in FOXG1 syndrome due to FOXG1 variants.MethodsWe compiled 30 new and 53 reported patients with a heterozygous pathogenic or likely pathogenic variant in FOXG1. We grouped patients according to type and location of the variant. Statistical analysis of molecular and clinical data was performed using Fisher's exact test and a nonparametric multivariate test.ResultsAmong the 30 new patients, we identified 19 novel FOXG1 variants. Among the total group of 83 patients, there were 54 variants: 20 frameshift (37%), 17 missense (31%), 15 nonsense (28%), and 2 in-frame variants (4%). Frameshift and nonsense variants are distributed over all FOXG1 protein domains; missense variants cluster within the conserved forkhead domain. We found a higher phenotypic variability than previously described. Genotype-phenotype association revealed significant differences in psychomotor development and neurological features between FOXG1 genotype groups. More severe phenotypes were associated with truncating FOXG1 variants in the N-terminal domain and the forkhead domain (except conserved site 1) and milder phenotypes with missense variants in the forkhead conserved site 1.ConclusionsThese data may serve for improved interpretation of new FOXG1 sequence variants and well-founded genetic counseling.
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13
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Ronen GM, Brady LI, Tarnopolsky MA. Males With MECP2 C-terminal-Related Atypical Rett Syndromes and Their Carrier Mothers. Pediatr Neurol 2017; 67:98-101. [PMID: 28089766 DOI: 10.1016/j.pediatrneurol.2016.10.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 10/05/2016] [Accepted: 10/09/2016] [Indexed: 11/26/2022]
Abstract
BACKGROUND This communication examines the expanding phenotypes of the MECP2 C-terminal atypical Rett syndromes in males and their affected carrier mothers. DESCRIPTIONS We describe three males with normal karyotypes who presented with congenital evolving complex neurodevelopmental encephalopathies with multifaceted symptomatology of hypotonia, epilepsy, ataxia, spasticity, movement disorders, behavioral issues, severe intellectual impairment, and communication skills, and a protracted regression phase followed by stabilization. These phenotypes did not prompt us to identify atypical Rett syndrome early in childhood. RESULTS Genetic analysis identified the two brothers with C-terminal truncation and the third male with C-terminal missense mutations. These mutations were inherited from their mothers, both of whom had incompletely characterized modest intellectual, mental health, social, and gastrointestinal impairments. Neither was independently able to care properly for their son(s). CONCLUSIONS Mutations of the MECP2 gene should be considered early in males with hypotonia, developmental delay, profound intellectual impairment, and seizures, associated with a mother with psychosocial, cognitive, and gastrointestinal impairments. Counseling and supporting mildly affected mothers requires both medical and social efforts.
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Affiliation(s)
- Gabriel M Ronen
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada.
| | - Lauren I Brady
- Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada
| | - Mark A Tarnopolsky
- Departments of Pediatrics and Medicine, McMaster University, Hamilton, Ontario, Canada
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14
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Desikan RS, Barkovich AJ. Malformations of cortical development. Ann Neurol 2016; 80:797-810. [PMID: 27862206 PMCID: PMC5177533 DOI: 10.1002/ana.24793] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Revised: 09/26/2016] [Accepted: 09/26/2016] [Indexed: 01/05/2023]
Abstract
Malformations of cortical development (MCDs) compose a diverse range of disorders that are common causes of neurodevelopmental delay and epilepsy. With improved imaging and genetic methodologies, the underlying molecular and pathobiological characteristics of several MCDs have been recently elucidated. In this review, we discuss genetic and molecular alterations that disrupt normal cortical development, with emphasis on recent discoveries, and provide detailed radiological features of the most common and important MCDs. Ann Neurol 2016;80:797-810.
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Affiliation(s)
- Rahul S. Desikan
- Neuroradiology Section, Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - A. James Barkovich
- Neuroradiology Section, Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
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15
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Williams AA, Mehler VJ, Mueller C, Vonhoff F, White R, Duch C. Apoptotic Activity of MeCP2 Is Enhanced by C-Terminal Truncating Mutations. PLoS One 2016; 11:e0159632. [PMID: 27442528 PMCID: PMC4956225 DOI: 10.1371/journal.pone.0159632] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Accepted: 07/05/2016] [Indexed: 11/22/2022] Open
Abstract
Methyl-CpG binding protein 2 (MeCP2) is a widely abundant, multifunctional protein most highly expressed in post-mitotic neurons. Mutations causing Rett syndrome and related neurodevelopmental disorders have been identified along the entire MECP2 locus, but symptoms vary depending on mutation type and location. C-terminal mutations are prevalent, but little is known about the function of the MeCP2 C-terminus. We employ the genetic efficiency of Drosophila to provide evidence that expression of p.Arg294* (more commonly identified as R294X), a human MECP2 E2 mutant allele causing truncation of the C-terminal domains, promotes apoptosis of identified neurons in vivo. We confirm this novel finding in HEK293T cells and then use Drosophila to map the region critical for neuronal apoptosis to a small sequence at the end of the C-terminal domain. In vitro studies in mammalian systems previously indicated a role of the MeCP2 E2 isoform in apoptosis, which is facilitated by phosphorylation at serine 80 (S80) and decreased by interactions with the forkhead protein FoxG1. We confirm the roles of S80 phosphorylation and forkhead domain transcription factors in affecting MeCP2-induced apoptosis in Drosophila in vivo, thus indicating mechanistic conservation between flies and mammalian cells. Our findings are consistent with a model in which C- and N-terminal interactions are required for healthy function of MeCP2.
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Affiliation(s)
- Alison A. Williams
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
- Institute of Zoology- Neurobiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Vera J. Mehler
- Institute of Zoology- Neurobiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | | | - Fernando Vonhoff
- Molecular, Cellular, and Developmental Biology Department, Yale University, New Haven, Connecticut, United States of America
| | - Robin White
- Institute of Physiology, University Medical Center, Mainz, Germany
| | - Carsten Duch
- Institute of Zoology- Neurobiology, Johannes Gutenberg University Mainz, Mainz, Germany
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16
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Boggio E, Pancrazi L, Gennaro M, Lo Rizzo C, Mari F, Meloni I, Ariani F, Panighini A, Novelli E, Biagioni M, Strettoi E, Hayek J, Rufa A, Pizzorusso T, Renieri A, Costa M. Visual impairment in FOXG1-mutated individuals and mice. Neuroscience 2016; 324:496-508. [DOI: 10.1016/j.neuroscience.2016.03.027] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 03/01/2016] [Accepted: 03/08/2016] [Indexed: 01/01/2023]
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17
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Reichow B, George-Puskar A, Lutz T, Smith IC, Volkmar FR. Brief report: systematic review of Rett syndrome in males. J Autism Dev Disord 2016; 45:3377-83. [PMID: 26254891 DOI: 10.1007/s10803-015-2519-1] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Rett syndrome (RTT) is a neurogenetic disorder in which a period of typical development is followed by loss of previously acquired skills. Once thought to occur exclusively in females, increasing numbers of male cases of RTT have been reported. This systematic review included 36 articles describing 57 cases of RTT in males. Mutations of the MECP2 gene were present in 56 % of cases, and 68 % of cases reported other genetic abnormalities. This is the first review of published reports of RTT in male patients.
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Affiliation(s)
- Brian Reichow
- AJ Pappanikou Center for Excellence in Developmental Disabilities, University of Connecticut Health Center, Farmington, CT, USA.
- University of Florida, 1345Q Norman Hall, PO Box 117050, Gainesville, FL, 32661-7050, USA.
| | | | - Tara Lutz
- University of Connecticut, Storrs, CT, USA
| | - Isaac C Smith
- AJ Pappanikou Center for Excellence in Developmental Disabilities, University of Connecticut Health Center, Farmington, CT, USA
- Yale Child Study Center, New Haven, CT, USA
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18
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Patriarchi T, Amabile S, Frullanti E, Landucci E, Lo Rizzo C, Ariani F, Costa M, Olimpico F, W Hell J, M Vaccarino F, Renieri A, Meloni I. Imbalance of excitatory/inhibitory synaptic protein expression in iPSC-derived neurons from FOXG1(+/-) patients and in foxg1(+/-) mice. Eur J Hum Genet 2015; 24:871-80. [PMID: 26443267 DOI: 10.1038/ejhg.2015.216] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Revised: 08/24/2015] [Accepted: 09/01/2015] [Indexed: 01/12/2023] Open
Abstract
Rett syndrome (RTT) is a severe neurodevelopmental disorder associated with mutations in either MECP2, CDKL5 or FOXG1. The precise molecular mechanisms that lead to the pathogenesis of RTT have yet to be elucidated. We recently reported that expression of GluD1 (orphan glutamate receptor δ-1 subunit) is increased in iPSC-derived neurons obtained from patients with mutations in either MECP2 or CDKL5. GluD1 controls synaptic differentiation and shifts the balance between excitatory and inhibitory synapses toward the latter. Thus, an increase in GluD1 might be a critical factor in the etiology of RTT by affecting the excitatory/inhibitory balance in the developing brain. To test this hypothesis, we generated iPSC-derived neurons from FOXG1(+/-) patients. We analyzed mRNA and protein levels of GluD1 together with key markers of excitatory and inhibitory synapses in these iPSC-derived neurons and in Foxg1(+/-) mouse fetal (E11.5) and adult (P70) brains. We found strong correlation between iPSC-derived neurons and fetal mouse brains, where GluD1 and inhibitory synaptic markers (GAD67 and GABA AR-α1) were increased, whereas the levels of a number of excitatory synaptic markers (VGLUT1, GluA1, GluN1 and PSD-95) were decreased. In adult mice, GluD1 was decreased along with all GABAergic and glutamatergic markers. Our findings further the understanding of the etiology of RTT by introducing a new pathological event occurring in the brain of FOXG1(+/-) patients during embryonic development and its time-dependent shift toward a general decrease in brain synapses.
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Affiliation(s)
- Tommaso Patriarchi
- Medical Genetics, University of Siena, Siena, Italy.,Department of Pharmacology, University of California, Davis, Davis, CA, USA
| | | | - Elisa Frullanti
- Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | | | | | - Francesca Ariani
- Medical Genetics, University of Siena, Siena, Italy.,Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
| | - Mario Costa
- Institute of Neuroscience, Italian National Research Council, Pisa, Italy.,Scuola Normale Superiore, Pisa, Italy
| | - Francesco Olimpico
- Institute of Neuroscience, Italian National Research Council, Pisa, Italy
| | - Johannes W Hell
- Department of Pharmacology, University of California, Davis, Davis, CA, USA
| | - Flora M Vaccarino
- Child Study Center, Yale University School of Medicine, New Haven, CT, USA.,Department of Neurobiology, Yale University School of Medicine, New Haven, CT, USA
| | - Alessandra Renieri
- Medical Genetics, University of Siena, Siena, Italy.,Genetica Medica, Azienda Ospedaliera Universitaria Senese, Siena, Italy
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19
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McMahon KQ, Papandreou A, Ma M, Barry BJ, Mirzaa GM, Dobyns WB, Scott RH, Trump N, Kurian MA, Paciorkowski AR. Familial recurrences of FOXG1-related disorder: Evidence for mosaicism. Am J Med Genet A 2015; 167A:3096-102. [PMID: 26364767 DOI: 10.1002/ajmg.a.37353] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Accepted: 08/13/2015] [Indexed: 12/18/2022]
Abstract
FOXG1-related disorders are caused by heterozygous mutations in FOXG1 and result in a spectrum of neurodevelopmental phenotypes including postnatal microcephaly, intellectual disability with absent speech, epilepsy, chorea, and corpus callosum abnormalities. The recurrence risk for de novo mutations in FOXG1-related disorders is assumed to be low. Here, we describe three unrelated sets of full siblings with mutations in FOXG1 (c.515_577del63, c.460dupG, and c.572T > G), representing familial recurrence of the disorder. In one family, we have documented maternal somatic mosaicism for the FOXG1 mutation, and all of the families presumably represent parental gonadal (or germline) mosaicism. To our knowledge, mosaicism has not been previously reported in FOXG1-related disorders. Therefore, this report provides evidence that germline mosaicism for FOXG1 mutations is a likely explanation for familial recurrence and should be considered during recurrence risk counseling for families of children with FOXG1-related disorders.
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Affiliation(s)
- Kelly Q McMahon
- Department of Neurology, University of Rochester Medical Center, Rochester, New York
| | - Apostolos Papandreou
- Developmental Neurosciences, UCL-Institute of Child Health, London, United Kingdom.,Department of Neurology, Great Ormond Street Hospital, London, United Kingdom.,Genetics and Genomics Medicine, UCL-Institute of Child Health, London, United Kingdom
| | - Mandy Ma
- University of Buffalo School of Medicine, Buffalo, New York
| | | | - Ghayda M Mirzaa
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - William B Dobyns
- Department of Pediatrics, Division of Genetic Medicine, University of Washington, Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, Washington
| | - Richard H Scott
- Genetics and Genomics Medicine, UCL-Institute of Child Health, London, United Kingdom.,North East Thames Regional Genetics Service, Great Ormond Street Hospital, London, United Kingdom
| | - Natalie Trump
- North East Thames Regional Genetics Service, Great Ormond Street Hospital, London, United Kingdom
| | - Manju A Kurian
- Developmental Neurosciences, UCL-Institute of Child Health, London, United Kingdom.,Department of Neurology, Great Ormond Street Hospital, London, United Kingdom
| | - Alex R Paciorkowski
- Department of Neurology, University of Rochester Medical Center, Rochester, New York.,Departments of Pediatrics and Biomedical Genetics, Center for Neural Development and Disease, University of Rochester Medical Center, Rochester, New York
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20
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Pantaleón F G, Juvier R T. [Molecular basis of Rett syndrome: A current look]. ACTA ACUST UNITED AC 2015; 86:142-51. [PMID: 26239053 DOI: 10.1016/j.rchipe.2015.07.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2013] [Accepted: 02/09/2015] [Indexed: 11/28/2022]
Abstract
UNLABELLED Rett syndrome (RS) is a neurodevelopmental disorder that exclusively affects girls, and occurs along with autism. It is very uncommon, and has five distinct forms, one classic and the others atypical, which generally compromise manual skills, language, and mobility, and widely associated with the appearance of stereotypy and early epilepsy. With the aim of updating the information about RS, a search was performed in the computer data bases of PubMed, Hinari, SCIELO and Medline, as well as consulting other web sites including OMIM, ORPHANET, GeneMap, Genetests, Proteins and Gene, using the descriptors "Síndrome de Rett", "genes y Síndrome de Rett", "Rett Syndrome gene", "Rett Syndrome", "Rett Syndrome gene therapy", and "Rett Syndrome review". Of the 1,348 articles found, 42 articles were selected, which reported 3 genes causing the syndrome: MECP2, CDKL5 and FOXG. The MECP2 gene is mutated in 80% of patients with classic RS, as well as in 40% of those affected by any of its atypical forms. RS with early epilepsy and the congenital variant are mainly due to variations in the CDKL5 and FOXG1 genes, respectively. CONCLUSIONS The diagnosis of RS is based on clinical criteria. However, the advances in molecular biology and genetics have opened a wide range of possibilities for diagnosing the different clinical forms that could not be classified before. Molecular analysis can help confirm the clinical criteria and provided information as regards the prognosis of the patient.
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Affiliation(s)
- Gretta Pantaleón F
- Departamento de Genética Molecular, Hospital Clínico Quirúrgico Hermanos Ameijeiras, La Habana, Cuba
| | - Tamara Juvier R
- Instituto de Neurología y Neurocirugía Prof. Rafael Estrada, La Habana, Cuba.
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21
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Byun CK, Lee JS, Lim BC, Kim KJ, Hwang YS, Chae JH. FOXG1 Mutation is a Low-Incidence Genetic Cause in Atypical Rett Syndrome. Child Neurol Open 2015; 2:2329048X14568151. [PMID: 28503589 PMCID: PMC5417036 DOI: 10.1177/2329048x14568151] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2014] [Revised: 11/28/2014] [Accepted: 12/03/2014] [Indexed: 11/15/2022] Open
Abstract
Due to the genetic and clinical heterogeneity of Rett syndrome, patients with nonclassic phenotypes are classified as an atypical Rett syndrome, that is, preserved speech variant, early seizure variant, and congenital variant. Respectively, MECP2, CDKL5, and FOXG1 have been found to be the causative genes, but FOXG1 variants are the rarest and least studied. We performed mutational analyses for FOXG1 on 11 unrelated patients without MECP2 and CDKL5 mutations, who were diagnosed with atypical Rett syndrome. One patient, who suffered from severe early-onset mental retardation and multiple-type intractable seizures, carried a novel, de novo FOXG1 mutation (p.Gln70Pro). This case concurs with previous studies that have reported yields of ∼10%. FOXG1-related atypical Rett syndrome is rare in Korean population, but screening of this gene in patients with severe mental retardation, microcephaly, and early-onset multiple seizure types without specific genetic causes can help broaden the phenotypic spectrum of the distinct FOXG1-related syndrome.
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Affiliation(s)
- Christine K. Byun
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children’s Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jin Sook Lee
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children’s Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Byung Chan Lim
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children’s Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Ki Joong Kim
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children’s Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Yong Seung Hwang
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children’s Hospital, Seoul National University College of Medicine, Seoul, Korea
| | - Jong-Hee Chae
- Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children’s Hospital, Seoul National University College of Medicine, Seoul, Korea
- Jong-Hee Chae, MD, PhD, Department of Pediatrics, Pediatric Clinical Neuroscience Center, Seoul National University Children’s Hospital, Seoul National University College of Medicine, 101 Daehakro Jongno-gu, Seoul 110-744, Korea.
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22
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Terrone G, Bienvenu T, Germanaud D, Barthez-Carpentier MA, Diebold B, Delanoe C, Passemard S, Auvin S. A case of Lennox-Gastaut syndrome in a patient with FOXG1-related disorder. Epilepsia 2014; 55:e116-9. [PMID: 25266269 DOI: 10.1111/epi.12800] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/15/2014] [Indexed: 01/20/2023]
Abstract
Lennox-Gastaut syndrome (LGS) is a drug-resistant epileptic encephalopathy of childhood with a heterogeneous etiology. Recently, genome-wide association studies have led to the identification of new de novo mutations associated with this epileptic syndrome. Herein, we report an 8-year-old child with intellectual disability, severe postnatal microcephaly, Rett-like features, and LGS, carrying a de novo missense mutation in the forkhead box G1 (FOXG1) gene. This gene is responsible for FOXG1 syndrome, characterized by severe postnatal microcephaly, moderate postnatal growth deficiency, mental retardation with poor social interaction, stereotyped behavior and dyskinesias, absent language, sleep disorders, and epilepsy. Nonspecific epilepsy syndromes have been associated with this genetic disorder. Thus, we hypothesize that FOXG1 might be a new candidate gene in the etiology of LGS and suggest screening for this gene in cases of LGS with concomitant microcephaly and clinical features overlapping with Rett syndrome.
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Affiliation(s)
- Gaetano Terrone
- AP-HP, Pediatric Neurology Department, Hospital Robert Debré, Paris, France; Inserm, U1141, Paris, France; Department of Translational Medicine, Section of Pediatrics, Federico II University, Naples, Italy
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23
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De Bruyn C, Vanderhasselt T, Tanyalçin I, Keymolen K, Van Rompaey KL, De Meirleir L, Jansen AC. Thin genu of the corpus callosum points to mutation in FOXG1 in a child with acquired microcephaly, trigonocephaly, and intellectual developmental disorder: a case report and review of literature. Eur J Paediatr Neurol 2014; 18:420-6. [PMID: 24388699 DOI: 10.1016/j.ejpn.2013.11.010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 11/13/2013] [Accepted: 11/16/2013] [Indexed: 01/04/2023]
Abstract
The FOXG1 syndrome is emerging as a relative new entity in paediatric neurology. We report a boy with acquired microcephaly, mental retardation and a thin genu of the corpus callosum. The combination of these findings led to mutation analysis of FOXG1. The patient was found to be heterozygous for a novel mutation in FOXG1, c.506dup (p.Lys170GInfsX285), which occurred de novo. This frameshift mutation disturbs the three functional domains of the FOXG1 gene. Hypo- or agenesis of the anterior corpus callosum in combination with acquired microcephaly and neurologic impairment can be an important clue for identifying patients with a mutation in FOXG1.
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Affiliation(s)
| | | | | | | | | | - Linda De Meirleir
- Paediatric Neurology Unit, Department of Paediatrics, UZ Brussel, Brussels, Belgium
| | - Anna C Jansen
- Paediatric Neurology Unit, Department of Paediatrics, UZ Brussel, Brussels, Belgium; Department of Public Health, Vrije Universiteit Brussel, Brussels, Belgium
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24
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Radial Glia, the Keystone of the Development of the Hippocampal Dentate Gyrus. Mol Neurobiol 2014; 51:131-41. [DOI: 10.1007/s12035-014-8692-y] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2014] [Accepted: 03/24/2014] [Indexed: 01/20/2023]
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25
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Miyoshi G, Fishell G. Dynamic FoxG1 expression coordinates the integration of multipolar pyramidal neuron precursors into the cortical plate. Neuron 2012; 74:1045-58. [PMID: 22726835 DOI: 10.1016/j.neuron.2012.04.025] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/05/2012] [Indexed: 01/20/2023]
Abstract
Pyramidal cells of the cerebral cortex are born in the ventricular zone and migrate through the intermediate zone to enter into the cortical plate. In the intermediate zone, these migrating precursors move tangentially and initiate the extension of their axons by transiently adopting a characteristic multipolar morphology. We observe that expression of the forkhead transcription factor FoxG1 is dynamically regulated during this transitional period. By utilizing conditional genetic strategies, we show that the downregulation of FoxG1 at the beginning of the multipolar cell phase induces Unc5D expression, the timing of which ultimately determines the laminar identity of pyramidal neurons. In addition, we demonstrate that the re-expression of FoxG1 is required for cells to transit out of the multipolar cell phase and to enter into the cortical plate. Thus, the dynamic expression of FoxG1 during migration within the intermediate zone is essential for the proper assembly of the cerebral cortex.
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Affiliation(s)
- Goichi Miyoshi
- NYU Neuroscience Institute, Department of Physiology and Neuroscience, Smilow Research Center, New York University School of Medicine, 522 First Avenue, New York, NY 10016, USA
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26
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Ellaway CJ, Ho G, Bettella E, Knapman A, Collins F, Hackett A, McKenzie F, Darmanian A, Peters GB, Fagan K, Christodoulou J. 14q12 microdeletions excluding FOXG1 give rise to a congenital variant Rett syndrome-like phenotype. Eur J Hum Genet 2012; 21:522-7. [PMID: 22968132 DOI: 10.1038/ejhg.2012.208] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Rett syndrome is a clinically defined neurodevelopmental disorder almost exclusively affecting females. Usually sporadic, Rett syndrome is caused by mutations in the X-linked MECP2 gene in ∼90-95% of classic cases and 40-60% of individuals with atypical Rett syndrome. Mutations in the CDKL5 gene have been associated with the early-onset seizure variant of Rett syndrome and mutations in FOXG1 have been associated with the congenital Rett syndrome variant. We report the clinical features and array CGH findings of three atypical Rett syndrome patients who had severe intellectual impairment, early-onset developmental delay, postnatal microcephaly and hypotonia. In addition, the females had a seizure disorder, agenesis of the corpus callosum and subtle dysmorphism. All three were found to have an interstitial deletion of 14q12. The deleted region in common included the PRKD1 gene but not the FOXG1 gene. Gene expression analysis suggested a decrease in FOXG1 levels in two of the patients. Screening of 32 atypical Rett syndrome patients did not identify any pathogenic mutations in the PRKD1 gene, although a previously reported frameshift mutation affecting FOXG1 (c.256dupC, p.Gln86ProfsX35) was identified in a patient with the congenital Rett syndrome variant. There is phenotypic overlap between congenital Rett syndrome variants with FOXG1 mutations and the clinical presentation of our three patients with this 14q12 microdeletion, not encompassing the FOXG1 gene. We propose that the primary defect in these patients is misregulation of the FOXG1 gene rather than a primary abnormality of PRKD1.
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Affiliation(s)
- Carolyn J Ellaway
- Western Sydney Genetics Program, Children's Hospital at Westmead, Sydney, New South Wales, Australia.
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27
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14q12 and severe Rett-like phenotypes: new clinical insights and physical mapping of FOXG1-regulatory elements. Eur J Hum Genet 2012; 20:1216-23. [PMID: 22739344 DOI: 10.1038/ejhg.2012.127] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The Forkhead box G1 (FOXG1) gene has been implicated in severe Rett-like phenotypes. It encodes the Forkhead box protein G1, a winged-helix transcriptional repressor critical for forebrain development. Recently, the core FOXG1 syndrome was defined as postnatal microcephaly, severe mental retardation, absent language, dyskinesia, and dysgenesis of the corpus callosum. We present seven additional patients with a severe Rett-like neurodevelopment disorder associated with de novo FOXG1 point mutations (two cases) or 14q12 deletions (five cases). We expand the mutational spectrum in patients with FOXG1-related encephalopathies and precise the core FOXG1 syndrome phenotype. Dysgenesis of the corpus callosum and dyskinesia are not always present in FOXG1-mutated patients. We believe that the FOXG1 gene should be considered in severely mentally retarded patients (no speech-language) with severe acquired microcephaly (-4 to-6 SD) and few clinical features suggestive of Rett syndrome. Interestingly enough, three 14q12 deletions that do not include the FOXG1 gene are associated with phenotypes very reminiscent to that of FOXG1-mutation-positive patients. We physically mapped a putative long-range FOXG1-regulatory element in a 0.43 Mb DNA segment encompassing the PRKD1 locus. In fibroblast cells, a cis-acting regulatory sequence located more than 0.6 Mb away from FOXG1 acts as a silencer at the transcriptional level. These data are important for clinicians and for molecular biologists involved in the management of patients with severe encephalopathies compatible with a FOXG1-related phenotype.
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28
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Kamien BA, Cardamone M, Lawson JA, Sachdev R. A genetic diagnostic approach to infantile epileptic encephalopathies. J Clin Neurosci 2012; 19:934-41. [PMID: 22617547 DOI: 10.1016/j.jocn.2012.01.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 01/12/2012] [Accepted: 01/19/2012] [Indexed: 12/29/2022]
Abstract
Epileptic encephalopathies are characterized by frequent severe seizures, and/or prominent interictal epileptiform discharges on the electroencephalogram, developmental delay or deterioration, and usually a poor prognosis. The epileptiform abnormalities themselves are believed to contribute to the progressive disturbance in cerebral function. Determining the underlying aetiology responsible for infantile epileptic encephalopathy is a clinical challenge worth undertaking to facilitate advice on the recurrence risk and to allow for the option of prenatal testing, as often this category of epilepsy is associated with devastating hardship for families. This review takes advantage of recently published studies that have identified new genes associated with epilepsy and focuses on known monogenic causes where detection is useful for the process of genetic counselling. Based on the review, we present a diagnostic work-up in order to triage specific genetic testing for infants presenting with an epileptic encephalopathy.
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Affiliation(s)
- Benjamin A Kamien
- Department of Medical Genetics, Sydney Children's Hospital, High St., Randwick, New South Wales 2031, Australia.
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Isoform-specific toxicity of Mecp2 in postmitotic neurons: suppression of neurotoxicity by FoxG1. J Neurosci 2012; 32:2846-55. [PMID: 22357867 DOI: 10.1523/jneurosci.5841-11.2012] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The methyl-CpG binding protein 2 (MeCP2) is a widely expressed protein, the mutations of which cause Rett syndrome. The level of MeCP2 is highest in the brain where it is expressed selectively in mature neurons. Its functions in postmitotic neurons are not known. The MeCP2 gene is alternatively spliced to generate two proteins with different N termini, designated as MeCP2-e1 and MeCP2-e2. The physiological significance of these two isoforms has not been elucidated, and it is generally assumed they are functionally equivalent. We report that in cultured cerebellar granule neurons induced to die by low potassium treatment and in Aβ-treated cortical neurons, Mecp2-e2 expression is upregulated whereas expression of the Mecp2-e1 isoform is downregulated. Knockdown of Mecp2-e2 protects neurons from death, whereas knockdown of the e1 isoform has no effect. Forced expression of MeCP2-e2, but not MeCP2-e1, promotes apoptosis in otherwise healthy neurons. We find that MeCP2-e2 interacts with the forkhead protein FoxG1, mutations of which also cause Rett syndrome. FoxG1 has been shown to promote neuronal survival and its downregulation leads to neuronal death. We find that elevated FoxG1 expression inhibits MeCP2-e2 neurotoxicity. MeCP2-e2 neurotoxicity is also inhibited by IGF-1, which prevents the neuronal death-associated downregulation of FoxG1 expression, and by Akt, the activation of which is necessary for FoxG1-mediated neuroprotection. Finally, MeCP2-e2 neurotoxicity is enhanced if FoxG1 expression is suppressed or in neurons cultured from FoxG1-haplodeficient mice. Our results indicate that Mecp2-e2 promotes neuronal death and that this activity is normally inhibited by FoxG1. Reduced FoxG1 expression frees MecP2-e2 to promote neuronal death.
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Takahashi S, Matsumoto N, Okayama A, Suzuki N, Araki A, Okajima K, Tanaka H, Miyamoto A. FOXG1 mutations in Japanese patients with the congenital variant of Rett syndrome. Clin Genet 2011; 82:569-73. [PMID: 22129046 DOI: 10.1111/j.1399-0004.2011.01819.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Rett syndrome (RTT) is a severe neurodevelopmental disorder characterized by microcephaly, psychomotor regression, seizures and stereotypical hand movements. Recently, deletions and inactivating mutations in FOXG1, encoding a brain-specific transcription factor that is critical for forebrain development, have been found to be associated with the congenital variant of RTT. Here we report the clinical features and molecular characteristics of two cases of the congenital variant of RTT. We conducted mutation screenings of FOXG1 in a cohort of 15 Japanese patients with a clinical diagnosis of atypical RTT but without MECP2 and CDKL5 mutations. Two unrelated female patients had heterozygous mutations (c.256dupC, p.Gln86ProfsX35 and c.689G>A, pArg230His). Both showed neurological symptoms from the neonatal period, including hypotonia, irritability and severe microcephaly. Further, their psychomotor development was severely impaired, as indicated by their inability to sit unaided or acquire speech sounds, and they had a hyperkinetic movement disorder, because both displayed hand stereotypies and jerky movements of the upper limbs. Brain magnetic resonance imaging scans revealed delayed myelination with hypoplasia of the corpus callosum and frontal lobe. These cases confirm the involvement of FOXG1 in the molecular etiology of the congenital variant of RTT and show the characteristic features of FOXG1-related disorder.
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Affiliation(s)
- S Takahashi
- Department of Pediatrics, Asahikawa Medical University, Asahikawa, Japan.
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De Filippis R, Pancrazi L, Bjørgo K, Rosseto A, Kleefstra T, Grillo E, Panighini A, Cardarelli F, Meloni I, Ariani F, Mencarelli MA, Hayek J, Renieri A, Costa M, Mari F. Expanding the phenotype associated with FOXG1 mutations and in vivo FoxG1 chromatin-binding dynamics. Clin Genet 2011; 82:395-403. [PMID: 22091895 DOI: 10.1111/j.1399-0004.2011.01810.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Mutations in the Forkhead box G1 (FOXG1) gene, a brain specific transcriptional factor, are responsible for the congenital variant of Rett syndrome. Until now FOXG1 point mutations have been reported in 12 Rett patients. Recently seven additional patients have been reported with a quite homogeneous severe phenotype designated as the FOXG1 syndrome. Here we describe two unrelated patients with a de novo FOXG1 point mutation, p.Gln46X and p.Tyr400X, respectively, having a milder phenotype and sharing a distinctive facial appearance. Although FoxG1 action depends critically on its binding to chromatin, very little is known about the dynamics of this process. Using fluorescence recovery after photobleaching, we showed that most of the GFP-FoxG1 fusion protein associates reversibly to chromatin whereas the remaining fraction is bound irreversibly. Furthermore, we showed that the two pathologic derivatives of FoxG1 described in this paper present a dramatic alteration in chromatin affinity and irreversibly bound fraction in comparison with Ser323fsX325 mutant (associated with a severe phenotype) and wild type Foxg1 protein. Our observations suggest that alterations in the kinetics of FoxG1 binding to chromatin might contribute to the pathological effects of FOXG1 mutations.
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Affiliation(s)
- R De Filippis
- Medical Genetics, Department of Biotechnology, University of Siena, Siena, Italy
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Van der Aa N, Van den Bergh M, Ponomarenko N, Verstraete L, Ceulemans B, Storm K. Analysis of FOXG1 Is Highly Recommended in Male and Female Patients with Rett Syndrome. Mol Syndromol 2011; 1:290-293. [PMID: 22190898 DOI: 10.1159/000330755] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/10/2011] [Indexed: 11/19/2022] Open
Abstract
We screened a cohort of 5 male and 20 female patients with a Rett spectrum disorder for mutations in the coding region of FOXG1, previously shown to cause the congenital variant of Rett syndrome. Two de novo mutations were identified. The first was a novel missense mutation, p.Ala193Thr (c.577G>A), in a male patient with congenital Rett syndrome, and the second was the p.Glu154GlyfsX301 (c.460dupG) truncating mutation in a female with classical Rett syndrome, a mutation that was previously reported in an independent patient. The overall rate of FOXG1 mutations in our cohort is 8%. Our findings stress the importance of FOXG1 analysis in male patients with Rett syndrome and in female patients when mutations in the MECP2 and CDKL5 genes have been excluded.
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Affiliation(s)
- N Van der Aa
- Department of Medical Genetics, University and University Hospital Antwerp, Antwerp
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Florian C, Bahi-Buisson N, Bienvenu T. FOXG1-Related Disorders: From Clinical Description to Molecular Genetics. Mol Syndromol 2011; 2:153-163. [PMID: 22670136 DOI: 10.1159/000327329] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Rett syndrome (RTT) is a severe neurodevelopmental disease that affects approximately 1 in 10,000 live female births and is often caused by mutations in the X-linked gene encoding methyl-CpG-binding protein 2 (MECP2). Mutations in loci other than MECP2 have also been found in individuals that have been labeled as atypical RTT. Among them, a mutation in the gene forkhead box G1 (FOXG1) has been involved in the molecular aetiology of the congenital variant of RTT. The FOXG1 gene encodes a winged-helix transcriptional repressor essential for the development of the ventral telencephalon in embryonic forebrain. Later, FOXG1 continues to be expressed in neurogenetic zones of the postnatal brain. Although RTT affects quasi-exclusively girls, FOXG1 mutations have also been identified in male patients. As far as we know, about 12 point mutations and 13 cases with FOXG1 molecular abnormalities (including translocation, duplication and large deletion on the chromosome 14q12) have been described in the literature. Affected individuals with FOXG1 mutations have shown dysmorphic features and Rett-like clinical course, including normal perinatal period, postnatal microcephaly, seizures and severe mental retardation. Interestingly, the existing animal models of FOXG1 deficiency showed similar phenotype, suggesting that animal models may be a fascinating model to understand this human disease. Here, we describe the impacts of FOXG1 mutations and their associated phenotypes in human and mouse models.
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Affiliation(s)
- C Florian
- Inserm, U1016, Université Paris Descartes, CNRS (UMR 8104), Paris, France
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Kortüm F, Das S, Flindt M, Morris-Rosendahl DJ, Stefanova I, Goldstein A, Horn D, Klopocki E, Kluger G, Martin P, Rauch A, Roumer A, Saitta S, Walsh LE, Wieczorek D, Uyanik G, Kutsche K, Dobyns WB. The core FOXG1 syndrome phenotype consists of postnatal microcephaly, severe mental retardation, absent language, dyskinesia, and corpus callosum hypogenesis. J Med Genet 2011; 48:396-406. [PMID: 21441262 DOI: 10.1136/jmg.2010.087528] [Citation(s) in RCA: 178] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
BACKGROUND Submicroscopic deletions in 14q12 spanning FOXG1 or intragenic mutations have been reported in patients with a developmental disorder described as a congenital variant of Rett syndrome. This study aimed to further characterise and delineate the phenotype of FOXG1 mutation positive patients. METHOD The study mapped the breakpoints of a 2;14 translocation by fluorescence in situ hybridisation and analysed three chromosome rearrangements in 14q12 by cytogenetic analysis and/or array comparative genomic hybridisation. The FOXG1 gene was sequenced in 210 patients, including 129 patients with unexplained developmental disorders and 81 MECP2 mutation negative individuals. RESULTS One known mutation, seen in two patients, and nine novel mutations of FOXG1 including two deletions, two chromosome rearrangements disrupting or displacing putative cis-regulatory elements from FOXG1, and seven sequence changes, are reported. Analysis of 11 patients in this study, and a further 15 patients reported in the literature, demonstrates a complex constellation of features including mild postnatal growth deficiency, severe postnatal microcephaly, severe mental retardation with absent language development, deficient social reciprocity resembling autism, combined stereotypies and frank dyskinesias, epilepsy, poor sleep patterns, irritability in infancy, unexplained episodes of crying, recurrent aspiration, and gastro-oesophageal reflux. Brain imaging studies reveal simplified gyral pattern and reduced white matter volume in the frontal lobes, corpus callosum hypogenesis, and variable mild frontal pachgyria. CONCLUSIONS These findings have significantly expanded the number of FOXG1 mutations and identified two affecting possible cis-regulatory elements. While the phenotype of the patients overlaps both classic and congenital Rett syndrome, extensive clinical evaluation demonstrates a distinctive and clinically recognisable phenotype which the authors suggest designating as the FOXG1 syndrome.
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Affiliation(s)
- Fanny Kortüm
- Institut für Humangenetik, Universitätsklinikum Hamburg-Eppendorf, Campus Forschung, Martinistraße 52, 20246 Hamburg, Germany
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