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Garcia ABDM, Viola GD, Corrêa BDS, Fischer TDS, Pinho MCDF, Rodrigues GM, Ashton-Prolla P, Rosset C. An overview of actionable and potentially actionable TSC1 and TSC2 germline variants in an online Database. Genet Mol Biol 2024; 46:e20230132. [PMID: 38373162 PMCID: PMC10876083 DOI: 10.1590/1678-4685-gmb-2023-0132] [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: 05/03/2023] [Accepted: 11/26/2023] [Indexed: 02/21/2024] Open
Abstract
Tuberous Sclerosis Complex (TSC) is caused by loss of function germline variants in the TSC1 or TSC2 tumor suppressor genes. Genetic testing for the detection of pathogenic variants in either TSC1 or TSC2 was implemented as a diagnostic criterion for TSC. However, TSC molecular diagnosis can be challenging due to the absence of variant hotspots and the high number of variants described. This review aimed to perform an overview of TSC1/2 variants submitted in the ClinVar database. Variants of uncertain significance (VUS), missense and single nucleotide variants were the most frequent in clinical significance (37-40%), molecular consequence (37%-39%) and variation type (82%-83%) categories in ClinVar in TSC1 and TSC2 variants, respectively. Frameshift and nonsense VUS have potential for pathogenic reclassification if further functional and segregation studies were performed. Indeed, there were few functional assays deposited in the database and literature. In addition, we did not observe hotspots for variation and many variants presented conflicting submissions regarding clinical significance. This study underscored the importance of disseminating molecular diagnostic results in a public database to render the information largely accessible and promote accurate diagnosis. We encourage the performance of functional studies evaluating the pathogenicity of TSC1/2 variants.
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Affiliation(s)
- Arthur Bandeira de Mello Garcia
- Hospital de Clínicas de Porto Alegre, Centro de Pesquisa Experimental, Laboratório de Medicina Genômica, Porto Alegre, RS, Brazil
- Universidade Federal do Rio Grande do Sul, Departamento de Genética, Programa de Pós-Graduação em Genética e Biologia Molecular, Porto Alegre, RS, Brazil
| | - Guilherme Danielski Viola
- Hospital de Clínicas de Porto Alegre, Centro de Pesquisa Experimental, Laboratório de Medicina Genômica, Porto Alegre, RS, Brazil
- Universidade Federal do Rio Grande do Sul, Departamento de Genética, Programa de Pós-Graduação em Genética e Biologia Molecular, Porto Alegre, RS, Brazil
| | - Bruno da Silveira Corrêa
- Hospital de Clínicas de Porto Alegre, Centro de Pesquisa Experimental, Laboratório de Medicina Genômica, Porto Alegre, RS, Brazil
- Universidade Federal do Rio Grande do Sul, Departamento de Genética, Programa de Pós-Graduação em Genética e Biologia Molecular, Porto Alegre, RS, Brazil
| | - Taís da Silveira Fischer
- Hospital de Clínicas de Porto Alegre, Centro de Pesquisa Experimental, Laboratório de Medicina Genômica, Porto Alegre, RS, Brazil
| | - Maria Clara de Freitas Pinho
- Hospital de Clínicas de Porto Alegre, Centro de Pesquisa Experimental, Laboratório de Medicina Genômica, Porto Alegre, RS, Brazil
- Centro Universitário CESUCA, Cachoeirinha, RS, Brazil
| | - Grazielle Motta Rodrigues
- Hospital de Clínicas de Porto Alegre, Centro de Pesquisa Experimental, Laboratório de Medicina Genômica, Porto Alegre, RS, Brazil
- Universidade Federal do Rio Grande do Sul, Programa de Pós-Graduação em Ciências Médicas, Porto Alegre, RS, Brazil
| | - Patricia Ashton-Prolla
- Hospital de Clínicas de Porto Alegre, Centro de Pesquisa Experimental, Laboratório de Medicina Genômica, Porto Alegre, RS, Brazil
- Universidade Federal do Rio Grande do Sul, Departamento de Genética, Programa de Pós-Graduação em Genética e Biologia Molecular, Porto Alegre, RS, Brazil
- Universidade Federal do Rio Grande do Sul, Programa de Pós-Graduação em Ciências Médicas, Porto Alegre, RS, Brazil
- Hospital de Clínicas de Porto Alegre, Serviço de Genética Médica, Porto Alegre, RS, Brazil
| | - Clévia Rosset
- Hospital de Clínicas de Porto Alegre, Centro de Pesquisa Experimental, Laboratório de Medicina Genômica, Porto Alegre, RS, Brazil
- Universidade Federal do Rio Grande do Sul, Programa de Pós-Graduação em Ciências Médicas, Porto Alegre, RS, Brazil
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Argani P, Medeiros LJ, Matoso A, Baraban E, Lotan T, Pawel BR, McKenney JK, Mehra R, Falzarano SM, Pallavajjalla A, Lin MT, Patel S, Rawwas J, Bendel AE, Gagan J, Palsgrove DN. "Oncocytoid Renal Cell Carcinomas After Neuroblastoma" Represent TSC -mutated Eosinophilic Solid and Cystic Renal Cell Carcinomas : Association With Prior Childhood Malignancy and Multifocality With Therapeutic Implications. Am J Surg Pathol 2023; 47:1335-1348. [PMID: 37522346 DOI: 10.1097/pas.0000000000002101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
The concept of oncocytoid renal cell carcinoma in patients who have survived neuroblastoma as a distinct biologic entity has been controversial since its original description in 1999. This is in part because similar oncocytoid renal cell carcinomas have been described in association with other pediatric cancers, and also because other renal cell carcinoma subtypes (such as MiT family translocation renal cell carcinoma) have been described in children who have survived neuroblastoma. We identified an index case of a child who survived medulloblastoma and developed multifocal bilateral oncocytoid renal cell carcinomas with morphology and immunophenotype compatible with eosinophilic solid and cystic renal cell carcinoma (ESC RCC) and demonstrated that both neoplasms harbored distinctive mutations in the TSC1/TSC2 genes. Remarkably, the child's remaining bilateral multifocal renal neoplasms completely responded to MTOR inhibitor therapy without need for further surgery. To confirm our hypothesis that oncocytoid renal cell carcinomas after childhood cancer represent ESC RCC, we obtained formalin-fixed paraffin-embedded tissue blocks from 2 previously published cases of oncocytoid renal cell carcinoma after neuroblastoma, confirmed that the morphology and immunophenotype was consistent with ESC RCC, and demonstrated that both cases harbored somatic TSC gene mutations. Both expressed markers previously associated with neoplasms harboring TSC gene mutations, glycoprotein nonmetastatic B, and cathepsin K. Of note, one of these patients had 2 ESC RCC which harbored distinctive TSC2 mutations, while the background kidney of the other patient had multiple small cysts lined by similar oncocytoid cells which showed loss of TSC2 protein. We then reviewed 3 of 4 cases from the original 1999 report of oncocytoid renal cell carcinomas after neuroblastoma, found that all 3 demonstrated morphology (including basophilic cytoplasmic stippling) that is characteristic of ESC RCC, showed that all 3 overexpressed glycoprotein nonmetastatic B, and showed that both cases with adequate material demonstrated loss of TSC2 protein and expressed cytokeratin 20 and cathepsin K by immunohistochemistry. In summary, "oncocytoid renal cell carcinomas after neuroblastoma" represent ESC RCC which are often multifocal in patients who have survived childhood cancer, likely representing an incompletely characterized tumor predisposition syndrome. MTOR-targeted therapy represents an effective therapeutic option for such patients to preserve functional nephrons.
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Affiliation(s)
- Pedram Argani
- Departments of Pathology
- Urology
- Oncology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - L Jeffrey Medeiros
- Department of Hematopathology, University of Texas MD Anderson Cancer Center, Houston
| | - Andres Matoso
- Departments of Pathology
- Urology
- Oncology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Ezra Baraban
- Departments of Pathology
- Urology
- Oncology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Tamara Lotan
- Departments of Pathology
- Urology
- Oncology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Bruce R Pawel
- Department of Pathology and Laboratory Medicine, Children's Hospital Los Angeles and Keck School of Medicine of the University of Southern California, Los Angeles, CA
| | - Jesse K McKenney
- Department of Pathology, Robert J. Tomsich Pathology and Laboratory Medicine Institute, Cleveland Clinic, Cleveland, OH
| | - Rohit Mehra
- Department of Pathology and Michigan Center for Translational Pathology (MCTP), University of Michigan School of Medicine, Ann Arbor, MI
| | - Sara M Falzarano
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida, Gainesville, FL
| | - Aparna Pallavajjalla
- Departments of Pathology
- Urology
- Oncology, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Ming-Tseh Lin
- Departments of Pathology
- Urology
- Oncology, Johns Hopkins University School of Medicine, Baltimore, MD
| | | | - Jawhar Rawwas
- Hematology/Oncology, Children's Minnesota, Minneapolis, MN
| | - Anne E Bendel
- Hematology/Oncology, Children's Minnesota, Minneapolis, MN
| | - Jeffrey Gagan
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX
| | - Doreen N Palsgrove
- Department of Pathology, University of Texas Southwestern Medical Center, Dallas, TX
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Farach LS, Northrup H, Nellist M, van Unen L, Hillman P, Klonowska K, Ekong R, Crino PB, Sing Au K. Mild TSC Phenotype and Non-Penetrance Associated with a Frameshift Variant in TSC2 Prompts Caution in Evaluating Pathogenicity of Frameshift Variants. Gene 2023:147566. [PMID: 37311496 DOI: 10.1016/j.gene.2023.147566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 06/06/2023] [Accepted: 06/09/2023] [Indexed: 06/15/2023]
Abstract
INTRODUCTION Technological advances in genetic testing, particularly the adoption of noninvasive prenatal screening (NIPS) for single gene disorders such as tuberous sclerosis complex (TSC, OMIM# 613254), mean that putative/possible pathogenetic DNA variants can be identified prior to the appearance of a disease phenotype. Without a phenotype, accurate prediction of variant pathogenicity is crucial. Here, we report a TSC2 frameshift variant, NM_000548.5(TSC2):c.4255_4256delCA, predicted to result in nonsense-mediated mRNA decay (NMD) and cessation of TSC2 protein production and thus pathogenic according to ACMG criteria, identified by NIPS and subsequently detected in family members with few or no symptoms of TSC. Due to the lack of TSC-associated features in the family, we hypothesized that the deletion created a non-canonical 5' donor site resulting in cryptic splicing and a transcript encoding active TSC2 protein. Verifying the predicted effect of the variant was key to designating pathogenicity in this case and should be considered for other frameshift variants in other genetic disorders. METHODS Phenotypic information on the family members was collected via review of the medical records and patient reports. RNA studies were performed using proband mRNA isolated from blood lymphocytes for RT-PCR and Sanger sequencing. Functional studies were performed by transient expression of the TSC2 variant proteins in cultured cells, followed by immunoblotting. RESULTS No family members harboring the variant met any major clinical diagnostic criteria for TSC, though a few minor features non-specific to TSC were present. RNA studies supported the hypothesis that the variant caused cryptic splicing, resulting in an mRNA transcript with an in-frame deletion of 93 base pairs r.[4255_4256del, 4251_4343del], p.[(Gln1419Valfs*104), (Gln1419_Ser1449del)]. Expression studies demonstrated that the canonical function of the resulting truncated TSC2 p.Gln1419_Ser1449del protein product was maintained and similar to wildtype. CONCLUSION Although most frameshift variants are likely to result in NMD, the NM_000548.5(TSC2):c.4255_4256delCA variant creates a cryptic 5' splice donor site, resulting in an in-frame deletion that retains TSC2 function, explaining why carriers of the variant do not have typical features of TSC. The information is important for this family and others with the same variant. Equally important is the lesson that predictions can be inaccurate, and that caution should be used when designating frameshift variants as pathogenic, especially when phenotypic information to corroborate testing results is unavailable. Our work demonstrates that functional RNA- and protein-based confirmation of the effects of DNA variants improves molecular genetic diagnostics.
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Affiliation(s)
- Laura S Farach
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth Houston) and Children's Memorial Hermann Hospital, Houston, Texas, USA.
| | - Hope Northrup
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth Houston) and Children's Memorial Hermann Hospital, Houston, Texas, USA
| | - Mark Nellist
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Leontine van Unen
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Paul Hillman
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth Houston) and Children's Memorial Hermann Hospital, Houston, Texas, USA
| | - Katarzyna Klonowska
- Cancer Genetics Laboratory, Division of Pulmonary and Critical Care Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Rosemary Ekong
- Research Department of Genetics, Evolution and Environment, Darwin Building, University College London, London, United Kingdom
| | - Peter B Crino
- Department of Neurology, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Kit Sing Au
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School at the University of Texas Health Science Center at Houston (UTHealth Houston) and Children's Memorial Hermann Hospital, Houston, Texas, USA
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Genetic analysis of 18 families with tuberous sclerosis complex. Neurogenetics 2022; 23:223-230. [DOI: 10.1007/s10048-022-00694-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 05/12/2022] [Indexed: 10/18/2022]
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Zhang N, Wang X, Tang Z, Qiu X, Guo Z, Huang D, Xiong H, Guo Q. The Correlation Between Tuberous Sclerosis Complex Genotype and Renal Angiomyolipoma Phenotype. Front Genet 2021; 11:575750. [PMID: 33679864 PMCID: PMC7933690 DOI: 10.3389/fgene.2020.575750] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 12/17/2020] [Indexed: 11/13/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is a rare multisystem autosomal dominant genetic disease that occurs between 1 in 6,000 and 1 in 10,000 live births. Additionally, renal angiomyolipoma is the most common form of renal disease in patients affected by TSC. Although a genetic mutation analysis of TSC is not rare, the correlation between the TSC gene mutation and renal angiomyolipoma phenotype is poorly understood. This study aims to analyze the mutation sites in 261 types of selected TSC patients. The results reveal that: (1) female patients develop more renal angiomyolipoma than male patients [p = 0.008, OR = 2.474, 95%CI (1.258–4.864)]; (2). The missense mutation of TSC1 led to a higher risk of renal angiomyolipoma [p < 0.01, OR = 15, 95%CI (2.859–78.691)], and in contrast, showed a reduced risk in patients with frameshift mutation [p = 0.03, OR = 0.252, 95%CI (0.07–0.912)]; (3). Patients with TSC2 mutations in the transcription activation domain 1 coding genes, had increased renal angiomyolipoma [p = 0.019, OR = 3.519, 95%CI (1.226–10.101)]. Therefore, our genotype-phenotype correlation study might shed light on the early monitoring and evaluation of renal angiomyolipoma in TSC patients.
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Affiliation(s)
- Nianyi Zhang
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xiaofang Wang
- Department of Dermatology and Venerology, University of Chinese Academy of Sciences Shenzhen Hospital, Shenzhen, China
| | - Zengqi Tang
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Xiaonan Qiu
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Zhixuan Guo
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Danqi Huang
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Hui Xiong
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Malignnt Tumor Epigenetic and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Qing Guo
- Department of Dermatology, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
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6
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Farach LS, Richard MA, Lupo PJ, Sahin M, Krueger DA, Wu JY, Bebin EM, Au KS, Northrup H. Epilepsy Risk Prediction Model for Patients With Tuberous Sclerosis Complex. Pediatr Neurol 2020; 113:46-50. [PMID: 33011641 PMCID: PMC10461434 DOI: 10.1016/j.pediatrneurol.2020.07.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 06/29/2020] [Accepted: 07/25/2020] [Indexed: 01/13/2023]
Abstract
BACKGROUND Individuals with tuberous sclerosis complex are at increased risk of epilepsy. Early seizure control improves developmental outcomes, making identifying at-risk patients critically important. Despite several identified risk factors, it remains difficult to predict. The purpose of the study was to evaluate the combined risk prediction of previously identified risk factors for epilepsy in individuals with tuberous sclerosis complex. METHODS The study group (n = 333) consisted of individuals with tuberous sclerosis complex who were enrolled in the Tuberous Sclerosis Complex Autism Center of Excellence Research Network and UT TSC Biobank. The outcome was defined as having an epilepsy diagnosis. Potential risk factors included sex, TSC genotype, and tuber presence. Logistic regression was used to calculate the odds ratio and P value for the association between each variable and epilepsy. A clinical risk prediction model incorporating all risk factors was built. Area under the curve was calculated to characterize the full model's ability to discriminate individuals with tuberous sclerosis complex with and without epilepsy. RESULTS The strongest risk for epilepsy was presence of tubers (95% confidence interval: 2.39 to 10.89). Individuals with pathogenic TSC2 variants were three times more likely (95% confidence interval: 1.55 to 6.36) to develop seizures compared with those with tuberous sclerosis complex from other causes. The combination of risk factors resulted in an area under the curve 0.73. CONCLUSIONS Simple characteristics of patients with tuberous sclerosis complex can be combined to successfully predict epilepsy risk. A risk assessment model that incorporates sex, TSC genotype, protective TSC2 missense variant, and tuber presence correctly predicts epilepsy in 73% of patients with tuberous sclerosis complex.
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Affiliation(s)
- Laura S Farach
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas.
| | - Melissa A Richard
- Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Houston, Texas
| | - Philip J Lupo
- Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Houston, Texas
| | - Mustafa Sahin
- Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Darcy A Krueger
- Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio
| | - Joyce Y Wu
- Division of Pediatric Neurology, UCLA Mattel Children's Hospital and David Geffen School of Medicine, Los Angeles, California
| | | | - Kit Sing Au
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Hope Northrup
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
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Savini MN, Mingarelli A, Peron A, La Briola F, Cervi F, Alfano RM, Canevini MP, Vignoli A. Electro-clinical and neurodevelopmental outcome in six children with early diagnosis of tuberous sclerosis complex and role of the genetic background. Ital J Pediatr 2020; 46:36. [PMID: 32216820 PMCID: PMC7099780 DOI: 10.1186/s13052-020-0801-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Accepted: 03/17/2020] [Indexed: 11/10/2022] Open
Abstract
Background Seizures in individuals affected by tuberous sclerosis complex (TSC) commonly develop in the first year of life, are often preceded by a progressive deterioration of the electroencephalogram (EEG), and likely influence developmental outcome. Although early diagnosis of TSC has offered a tremendous opportunity to monitor affected patients before seizure onset, reports of the neurological manifestations of TSC in infants before seizure onset are still scarce. Here we describe early EEG activity, clinical and genetic data and developmental assessment in a group of TSC infants, with the aim of identifying possible prognostic factors for neurodevelopmental outcome. Methods We report on six infants diagnosed with TSC pre- or perinatally, who underwent serial Video-EEG recordings during the first two years of life. EEGs were classified based on distribution and intensity of interictal epileptiform discharges, and Vigabatrin was introduced in case of ictal discharges. Psychomotor development, cognitive functioning and behavioral problems were assessed through standardized scales. Molecular testing included analysis for point mutations and deletions/duplications in TSC1 and TSC2. Results EEG abnormalities appeared at a mean age of 4 months. Four of the six patients developed seizures. EEG abnormalities preceded the onset of clinical seizures in all of them. The two individuals with good seizure control showed normal development, while the other two exhibited psychomotor delays. The patients who did not develop seizures had normal development. A pathogenic variant in the TSC2 gene was detected in all patients but one. The one without a mutation identified did not develop seizures and showed normal neurodevelopment. Of note, the two patients presenting with the worst outcome (that is, poor seizure control and intellectual/behavioral disability) both carried pathogenic variants in the GAP domain of TSC2. Conclusion Our report supports the importance of EEG monitoring before seizure onset in patients with TSC, and the correlation between prompt seizure control and positive neurodevelopmental outcome, regardless of seizure type. Our results also indicate a possible role of the genetic background in influencing the outcome.
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Affiliation(s)
- M N Savini
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142, Milan, Italy
| | - A Mingarelli
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy
| | - A Peron
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142, Milan, Italy. .,Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA. .,Human Pathology and Molecular Pathology Unit, San Paolo Hospital, Milan, Italy.
| | - F La Briola
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy
| | - F Cervi
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy
| | - R M Alfano
- Human Pathology and Molecular Pathology Unit, San Paolo Hospital, Milan, Italy
| | - M P Canevini
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142, Milan, Italy
| | - A Vignoli
- Child Neuropsychiatric Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Via di Rudinì 8, 20142, Milan, Italy
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Farach LS, Pearson DA, Woodhouse JP, Schraw JM, Sahin M, Krueger DA, Wu JY, Bebin EM, Lupo PJ, Au KS, Northrup H. Tuberous Sclerosis Complex Genotypes and Developmental Phenotype. Pediatr Neurol 2019; 96:58-63. [PMID: 31005478 PMCID: PMC6837240 DOI: 10.1016/j.pediatrneurol.2019.03.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/25/2019] [Accepted: 03/06/2019] [Indexed: 10/27/2022]
Abstract
BACKGROUND Children with tuberous sclerosis complex (TSC), caused by pathogenic variants in TSC1/TSC2, are at risk for intellectual disability. TSC2 pathogenic variants appear to increase the risk, compared with TSC1. However, the effect of TSC2 pathogenic variants on early and specific domains of development hasn't been studied. Using an extensively phenotyped group, we aimed to characterize differences in early intellectual development between genotypes. METHODS The study group (n = 92) included participants with TSC enrolled in a multicenter study involving genetic testing and detailed prospective phenotyping including the Mullen Scales of Early Learning, a validated measure of cognition, language, and motor development in babies and preschool children. Mean T-scores at 24 months for each Mullen Scales of Early Learning domain were calculated for children with, versus without, a TSC2 pathogenic variant. Multivariable linear regression models were used to compare the groups, adjusting for seizures. RESULTS T-scores on every Mullen Scales of Early Learning domain were significantly worse in the TSC2 group. Below average composite scores were present in three-fourths of the TSC2 group, compared with one-fourth of those without TSC2. Having a TSC2 pathogenic variant was associated with lower composite Mullen Scales of Early Learning scores, even when corrected for seizures. CONCLUSIONS In a well-characterized patient population with standardized assessment of multiple aspects of development, we found that having a TSC2 pathogenic variant was associated with significantly lower Mullen Scales of Early Learning scores at age 24 months, independent of seizures. These data suggest that a baby with a TSC2 pathogenic variant is at high risk for significant developmental delays by 24 months.
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Affiliation(s)
- Laura S. Farach
- Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas,Communications should he addressed to: Laura S. Farach; 6431 Fannin Street MSB 3.142; Houston, TX 77030., (L.S. Farach)
| | - Deborah A. Pearson
- Department of Psychiatry, Division of Child and Adolescent Psychiatry, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - John P. Woodhouse
- Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Houston, Texas
| | - Jeremy M. Schraw
- Department of Medicine, Section of Epidemiology and Population Sciences, Baylor College of Medicine, Houston, Texas
| | - Mustafa Sahin
- Translational Neuroscience Center, Department of Neurology, Boston Children’s Hospital, Harvard Medical School, Boston, Massachusetts
| | - Darcy A. Krueger
- Division of Neurology, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio
| | - Joyce Y. Wu
- Division of Pediatric Neurology, UCLA Mattel Children’s Hospital and David Geffen School of Medicine, Los Angeles, California
| | | | - Philip J. Lupo
- Department of Pediatrics, Section of Hematology-Oncology, Baylor College of Medicine, Houston, Texas
| | - Kit Sing Au
- Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Hope Northrup
- Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
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Salussolia CL, Klonowska K, Kwiatkowski DJ, Sahin M. Genetic Etiologies, Diagnosis, and Treatment of Tuberous Sclerosis Complex. Annu Rev Genomics Hum Genet 2019; 20:217-240. [PMID: 31018109 DOI: 10.1146/annurev-genom-083118-015354] [Citation(s) in RCA: 88] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder that affects multiple organ systems due to an inactivating variant in either TSC1 or TSC2, resulting in the hyperactivation of the mechanistic target of rapamycin (mTOR) pathway. Dysregulated mTOR signaling results in increased cell growth and proliferation. Clinically, TSC patients exhibit great phenotypic variability, but the neurologic and neuropsychiatric manifestations of the disease have the greatest morbidity and mortality. TSC-associated epilepsy occurs in nearly all patients and is often difficult to treat because it is refractory to multiple antiseizure medications. The advent of mTOR inhibitors offers great promise in the treatment of TSC-associated epilepsy and other neurodevelopmental manifestations of the disease; however, the optimal timing of therapeutic intervention is not yet fully understood.
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Affiliation(s)
- Catherine L Salussolia
- F.M. Kirby Neurobiology Center, Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA;
| | - Katarzyna Klonowska
- Division of Pulmonary and Critical Care Medicine and Division of Genetics, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - David J Kwiatkowski
- Division of Pulmonary and Critical Care Medicine and Division of Genetics, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Mustafa Sahin
- F.M. Kirby Neurobiology Center, Translational Neuroscience Center, Department of Neurology, Boston Children's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA;
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10
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Ashida A, Matsumura H, Fujii Y, Nakakura H, Shirasu A, Tamai H. Everolimus improved renal function without reducing the size of a kidney angiomyolipoma in a patient with tuberous sclerosis complex: a case report. RENAL REPLACEMENT THERAPY 2018. [DOI: 10.1186/s41100-018-0166-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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11
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Canevini MP, Kotulska-Jozwiak K, Curatolo P, La Briola F, Peron A, Słowińska M, Strzelecka J, Vignoli A, Jóźwiak S. Current concepts on epilepsy management in tuberous sclerosis complex. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:299-308. [PMID: 30255982 DOI: 10.1002/ajmg.c.31652] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 08/21/2018] [Accepted: 08/23/2018] [Indexed: 12/12/2022]
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant neurocutaneous disease affecting approximately 1 in 6,000 people, and represents one of the most common genetic causes of epilepsy. Epilepsy affects 90% of the patients and appears in the first 2 years of life in the majority of them. Early onset of epilepsy in the first 12 months of life is associated with high risk of cognitive decline and neuropsychiatric problems including autism. Prenatal or early infantile diagnosis of TSC, before the onset of epilepsy, provides a unique opportunity to monitor EEG before the onset of clinical seizures, thus enabling early intervention in the process of epileptogenesis. In this review, we discuss the current status of knowledge on epileptogenesis in TSC, and present recommendations of American and European experts in the field of epilepsy.
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Affiliation(s)
- Maria Paola Canevini
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | | | - Paolo Curatolo
- Department of Pediatric Neuropsychiatry, Tor Vergata University, Rome, Italy
| | - Francesca La Briola
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Angela Peron
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Milan, Italy.,Division of Medical Genetics, Department of Pediatrics, University of Utah, Salt Lake City, Utah
| | - Monika Słowińska
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland.,Department of Pediatric Neurology, Warsaw Medical University, Warsaw, Poland
| | - Jolanta Strzelecka
- Department of Pediatric Neurology, Warsaw Medical University, Warsaw, Poland
| | - Aglaia Vignoli
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Sergiusz Jóźwiak
- Department of Neurology and Epileptology, The Children's Memorial Health Institute, Warsaw, Poland.,Department of Pediatric Neurology, Warsaw Medical University, Warsaw, Poland
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12
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Peron A, Au KS, Northrup H. Genetics, genomics, and genotype-phenotype correlations of TSC: Insights for clinical practice. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:281-290. [PMID: 30255984 DOI: 10.1002/ajmg.c.31651] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 08/22/2018] [Indexed: 01/28/2023]
Abstract
Tuberous Sclerosis Complex (TSC) is a multisystem autosomal dominant condition caused by inactivating pathogenic variants in either the TSC1 or the TSC2 gene, leading to hyperactivation of the mTOR pathway. Here, we present an update on the genetic and genomic aspects of TSC, with a focus on clinical and laboratory practice. We briefly summarize the structure of TSC1 and TSC2 as well as their protein products, and discuss current diagnostic testing, addressing mosaicism. We consider genotype-phenotype correlations as an example of precision medicine, and discuss genetic counseling in TSC, with the aim of providing geneticists and health care practitioners involved in the care of TSC individuals with useful tools for their practice.
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Affiliation(s)
- Angela Peron
- Child Neuropsychiatry Unit-Epilepsy Center (Service of Medical Genetics), San Paolo Hospital, Department of Health Sciences, Università degli Studi di Milano, Milan, Italy.,Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, Salt Lake City, Utah
| | - Kit Sing Au
- Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Hope Northrup
- Department of Pediatrics, Division of Medical Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
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13
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Papadopoulou A, Dinopoulos A, Koutsodontis G, Pons R, Vorgia P, Koute V, Vratimos A, Zafeiriou D. Screening for TSC1 and TSC2 mutations using NGS in Greek children with tuberous sclerosis syndrome. Eur J Paediatr Neurol 2018; 22:419-426. [PMID: 29500070 DOI: 10.1016/j.ejpn.2018.01.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 01/12/2018] [Accepted: 01/31/2018] [Indexed: 01/15/2023]
Abstract
Tuberous Sclerosis Complex (TSC) is a rare neurocutaneous syndrome inherited by an autosomal dominant manner. The disorder is commonly manifested by the presence of multiple benign tumors located in numerous tissues, including the brain, heart, skin and kidneys. Seizures, autism, developmental and behavioral delay, as well as non-neurological phenotypic findings, are suggestive of TSC. The identification of one pathogenic mutation in either the TSC1 or TSC2 genes is considered to be an independent diagnostic criterion. In our study, seventeen Greek patients, 2yo on average, were analyzed for the presence of pathogenic germline mutations in the aforementioned loci by Next-Generation Sequencing. A TSC1/2 gene panel was designed for the molecular diagnosis of the disease. Patients underwent initial diagnosis based on their clinical symptoms, most frequently involving the presence of skin lesions and/or epilepsy. Only one case was familial. Sixteen different genetic alterations were identified in TSC1 and TSC2 genes in fifteen patients, giving a 88% detection rate by employing NGS technology. Overall, most pathogenic mutations (11/15) identified were located in the TSC2 gene with exon 41 being the most frequent. With respect to genotype-phenotype association, no patient TSC1 (+) developed SEGA or renal cysts. No significant differences were observed between different types of TSC2 mutations and any clinical feature. Sequencing also revealed 18 different SNPs across the TSC1 and 20 across the TSC2 genes. This is the first registry of the genetic profile of TSC patients in Greece using a custom-made gene panel as molecular diagnostic tool.
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Affiliation(s)
| | - Argyrios Dinopoulos
- 3rd Department of Pediatrics, University General Hospital « Attikon », University of Athens, Greece
| | | | - Roser Pons
- 1st Department of Pediatrics, Agia Sofia Hospital, National and Kapodistrian University of Athens, Athens, Greece
| | - Pelagia Vorgia
- Pediatric Department, University Hospital of Heraklion, Crete, Greece
| | - Vasiliki Koute
- Pediatric Department, University Hospital of Larissa, University of Thessaly, Larissa, Greece
| | | | - Dimitrios Zafeiriou
- 1st Department of Pediatrics, « Hippokratio » General Hospital, Aristotle University, Thessaloniki, Greece.
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14
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Peron A, Vignoli A, Briola FL, Morenghi E, Tansini L, Alfano RM, Bulfamante G, Terraneo S, Ghelma F, Banderali G, Viskochil DH, Carey JC, Canevini MP. Deep phenotyping of patients with Tuberous Sclerosis Complex and no mutation identified in TSC1 and TSC2. Eur J Med Genet 2018; 61:403-410. [PMID: 29432982 DOI: 10.1016/j.ejmg.2018.02.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/12/2018] [Accepted: 02/08/2018] [Indexed: 01/08/2023]
Abstract
Tuberous Sclerosis Complex (TSC) is a multisystemic condition caused by mutations in TSC1 or TSC2, but a pathogenic variant is not identified in up to 10% of the patients. The aim of this study was to delineate the phenotype of pediatric and adult patients with a definite clinical diagnosis of TSC and no mutation identified in TSC1 or TSC2. We collected molecular and clinical data of 240 patients with TSC, assessing over 50 variables. We compared the phenotype of the homogeneous group of individuals with No Mutation Identified (NMI) with that of TSC patients with a TSC1 and TSC2 pathogenic variant. 9.17% of individuals were classified as NMI. They were diagnosed at an older age (p = 0.001), had more frequent normal cognition (p < 0.001) and less frequent epilepsy (p = 0.010), subependymal nodules (p = 0.022) and giant cell astrocytomas (p = 0.008) than patients with TSC2 pathogenic variants. NMI individuals showed more frequent bilateral and larger renal angiomyolipomas (p = 0.001; p = 0.003) and pulmonary involvement (trend) than patients with TSC1 pathogenic variants. Only one NMI individual had intellectual disability. None presented with a subependymal giant cell astrocytoma. Other medical problems not typical of TSC were found in 42.86%, without a recurrent pattern of abnormalities. Other TSC-associated neuropsychiatric disorders and drug-resistance in epilepsy were equally frequent in the three groups. This study provides a systematic clinical characterization of patients with TSC and facilitates the delineation of a distinctive phenotype indicative of NMI patients, with important implications for surveillance.
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Affiliation(s)
- Angela Peron
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy; Department of Health Sciences, Università degli Studi di Milano, Milan, Italy; Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA.
| | - Aglaia Vignoli
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy; Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
| | - Francesca La Briola
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy
| | - Emanuela Morenghi
- Biostatistics Unit, Humanitas Clinical and Research Center, Milan, Italy; Department of Biomedical Sciences, Humanitas University, Milan, Italy
| | - Lucia Tansini
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy
| | - Rosa Maria Alfano
- Human Pathology and Molecular Pathology Unit, San Paolo Hospital, Milan, Italy
| | - Gaetano Bulfamante
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy; Human Pathology and Molecular Pathology Unit, San Paolo Hospital, Milan, Italy
| | - Silvia Terraneo
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy; Respiratory Unit, San Paolo Hospital, Milan, Italy
| | - Filippo Ghelma
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy; DAMA (Disabled Advanced Medical Assistance), San Paolo Hospital, Milan, Italy
| | - Giuseppe Banderali
- Department of Health Sciences, Università degli Studi di Milano, Milan, Italy; Pediatrics Unit, San Paolo Hospital, Milan, Italy
| | - David H Viskochil
- Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - John C Carey
- Department of Pediatrics, Division of Medical Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Maria Paola Canevini
- Child Neuropsychiatry Unit - Epilepsy Center, San Paolo Hospital, Milan, Italy; Department of Health Sciences, Università degli Studi di Milano, Milan, Italy
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15
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Farach LS, Gibson WT, Sparagana SP, Nellist M, Stumpel CTRM, Hietala M, Friedman E, Pearson DA, Creighton SP, Wagemans A, Segel R, Ben-Shalom E, Au KS, Northrup H. TSC2 c.1864C>T variant associated with mild cases of tuberous sclerosis complex. Am J Med Genet A 2017; 173:771-775. [PMID: 28211972 DOI: 10.1002/ajmg.a.38083] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2016] [Accepted: 11/21/2016] [Indexed: 11/08/2022]
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominantly inherited disorder with variable expressivity associated with hamartomatous tumors, abnormalities of the skin, and neurologic problems including seizures, intellectual disability, and autism. TSC is caused by pathogenic variants in either TSC1 or TSC2. In general, TSC2 pathogenic variants are associated with a more severe phenotype than TSC1 pathogenic variants. Here, we report a pathogenic TSC2 variant, c.1864C>T, p.(Arg622Trp), associated with a mild phenotype, with most carriers meeting fewer than two major clinical diagnostic criteria for TSC. This finding has significant implications for counseling patients regarding prognosis. More patient data are required before changing the surveillance recommendations for patients with the reported variant. However, consideration should be given to tailoring surveillance recommendations for all pathogenic TSC1 and TSC2 variants with documented milder clinical sequelae. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Laura S Farach
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - William T Gibson
- Department of Medical Genetics, BC Children's Hospital and UBC, Vancouver, British Columbia, Canada
| | - Steven P Sparagana
- Division of Neurology, Texas Scottish Rite Hospital for Children and University of Texas Southwestern Medical School, Dallas, Texas
| | - Mark Nellist
- Department of Clinical Genetics, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Connie T R M Stumpel
- Department of Clinical Genetics and School for Oncology and Developmental Biology (GROW), Maastricht University Medical Center (MUMC), Maastricht, The Netherlands
| | - Marja Hietala
- Department of Clinical Genetics and Department of Medical Biochemistry and Genetics, University of Turku and Turku University Hospital, Turku, Finland
| | - Elliott Friedman
- Department of Diagnostic and Interventional Imaging, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Deborah A Pearson
- Division of Child and Adolescent Psychiatry, Department of Psychiatry, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Susan P Creighton
- Department of Medical Genetics, BC Women's Hospital and UBC, Vancouver, British Columbia, Canada
| | - Annemiek Wagemans
- Department of Clinical Genetics and School for Oncology and Developmental Biology (GROW), Maastricht University Medical Center (MUMC), Maastricht, The Netherlands.,Koraalgroep, Maasveld, Maastricht, The Netherlands
| | - Reveel Segel
- Medical Genetics Institute, Shaare Zedek Medical Center and the Hebrew University School of Medicine, Jerusalem, Israel
| | - Efrat Ben-Shalom
- Department of Pediatric Nephrology, Shaare Zedek Medical Center, Jerusalem, Israel
| | - Kit Sing Au
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
| | - Hope Northrup
- Division of Medical Genetics, Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas
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16
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Rosset C, Vairo F, Bandeira IC, Correia RL, de Goes FV, da Silva RTB, Bueno LSM, de Miranda Gomes MCS, Galvão HDCR, Neri JICF, Achatz MI, Netto CBO, Ashton-Prolla P. Molecular analysis of TSC1 and TSC2 genes and phenotypic correlations in Brazilian families with tuberous sclerosis. PLoS One 2017; 12:e0185713. [PMID: 28968464 PMCID: PMC5624610 DOI: 10.1371/journal.pone.0185713] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 09/18/2017] [Indexed: 12/22/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant multisystem disorder characterized by the development of multiple hamartomas in many organs and tissues. It occurs due to inactivating mutations in either of the two genes, TSC1 and TSC2, following a second hit in a tumor suppressor gene in most hamartomas. Comprehensive screening for mutations in both the TSC1 and TSC2 loci has been performed in several cohorts of patients and a broad spectrum of pathogenic mutations have been described. In Brazil, there is no data regarding incidence and prevalence of tuberous sclerosis and mutations in TSC1 and TSC2. We analyzed both genes in 53 patients with high suspicion of tuberous sclerosis using multiplex-ligation dependent probe amplification and a customized next generation sequencing panel. Confirmation of all variants was done by the Sanger method. We identified 50 distinct variants in 47 (89%) of the patients. Five were large rearrangements and 45 were point mutations. The symptoms presented by our series of patients were not different between male and female individuals, except for the more common occurrence of shagreen patch in women (p = 0.028). In our series, consistent with other studies, TSC2 mutations were associated with a more severe phenotypic spectrum than TSC1 mutations. This is the first study that sought to characterize the molecular spectrum of Brazilian individuals with tuberous sclerosis.
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Affiliation(s)
- Clévia Rosset
- Laboratório de Medicina Genômica – Centro de Pesquisa Experimental – Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Programa de pós-graduação em genética e biologia molecular, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Filippo Vairo
- Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Isabel Cristina Bandeira
- Laboratório de Medicina Genômica – Centro de Pesquisa Experimental – Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Rudinei Luis Correia
- Laboratório de Medicina Genômica – Centro de Pesquisa Experimental – Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
| | - Fernanda Veiga de Goes
- Instituto Fernandes Figueira, Fundação Osvaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | | | | | - João I. C. F. Neri
- Centro Especializado em Reabilitação e Habilitação, Natal, Rio Grande do Norte, Brazil
| | - Maria Isabel Achatz
- A.C. Camargo Cancer Center, São Paulo, São Paulo, Brazil
- Clinical Genetics Branch, Division of Cancer Epidemiology & Genetics, National Cancer Institute, National Institutes of Health, Rockville, United States of America
| | | | - Patricia Ashton-Prolla
- Laboratório de Medicina Genômica – Centro de Pesquisa Experimental – Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Programa de pós-graduação em genética e biologia molecular, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
- Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre, Porto Alegre, Rio Grande do Sul, Brazil
- Departamento de Genética - Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
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17
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Novel TSC1 and TSC2 gene mutations in Chinese patients with tuberous sclerosis complex. Clin Neurol Neurosurg 2017; 154:104-108. [DOI: 10.1016/j.clineuro.2017.01.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/26/2016] [Accepted: 01/21/2017] [Indexed: 11/18/2022]
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18
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Rosset C, Netto CBO, Ashton-Prolla P. TSC1 and TSC2 gene mutations and their implications for treatment in Tuberous Sclerosis Complex: a review. Genet Mol Biol 2017; 40:69-79. [PMID: 28222202 PMCID: PMC5409767 DOI: 10.1590/1678-4685-gmb-2015-0321] [Citation(s) in RCA: 85] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 03/01/2016] [Indexed: 01/08/2023] Open
Abstract
Tuberous sclerosis complex is an autosomal dominant disorder characterized by skin
manifestations and formation of multiple tumors in different organs, mainly in the
central nervous system. Tuberous sclerosis is caused by the mutation of one of two
tumor suppressor genes, TSC1 or TSC2. Currently,
the development of novel techniques and great advances in high-throughput genetic
analysis made mutation screening of the TSC1 and
TSC2 genes more widely available. Extensive studies of the
TSC1 and TSC2 genes in patients with TSC
worldwide have revealed a wide spectrum of mutations. Consequently, the discovery of
the underlying genetic defects in TSC has furthered our
understanding of this complex genetic disorder, and genotype-phenotype correlations
are becoming possible, although there are still only a few clearly established
correlations. This review focuses on the main symptoms and genetic alterations
described in TSC patients from 13 countries in three continents, as well as on
genotype-phenotype correlations established to date. The determination of
genotype-phenotype correlations may contribute to the establishment of successful
personalized treatment for TSC.
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Affiliation(s)
- Clévia Rosset
- Laboratório de Medicina Genômica, Centro de Pesquisa Experimental. Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil.,Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
| | | | - Patricia Ashton-Prolla
- Laboratório de Medicina Genômica, Centro de Pesquisa Experimental. Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil.,Programa de Pós-Graduação em Genética e Biologia Molecular, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.,Serviço de Genética Médica, Hospital de Clínicas de Porto Alegre (HCPA), Porto Alegre, RS, Brazil.,Departamento de Genética, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil
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19
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Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder that affects multiple organ systems and is caused by loss-of-function mutations in one of two genes: TSC1 or TSC2. The disorder can affect both adults and children. First described in depth by Bourneville in 1880, it is now estimated that nearly 2 million people are affected by the disease worldwide. The clinical features of TSC are distinctive and can vary widely between individuals, even within one family. Major features of the disease include tumours of the brain, skin, heart, lungs and kidneys, seizures and TSC-associated neuropsychiatric disorders, which can include autism spectrum disorder and cognitive disability. TSC1 (also known as hamartin) and TSC2 (also known as tuberin) form the TSC protein complex that acts as an inhibitor of the mechanistic target of rapamycin (mTOR) signalling pathway, which in turn plays a pivotal part in regulating cell growth, proliferation, autophagy and protein and lipid synthesis. Remarkable progress in basic and translational research, in addition to several randomized controlled trials worldwide, has led to regulatory approval of the use of mTOR inhibitors for the treatment of renal angiomyolipomas, brain subependymal giant cell astrocytomas and pulmonary lymphangioleiomyomatosis, but further research is needed to establish full indications of therapeutic treatment. In this Primer, we review the state-of-the-art knowledge in the TSC field, including the molecular and cellular basis of the disease, medical management, major knowledge gaps and ongoing research towards a cure.
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Affiliation(s)
- Elizabeth P Henske
- Pulmonary and Critical Care Medicine Division, Brigham and Women's Hospital, Harvard Medical School, 15 Francis Street, Boston, Massachusetts 02115, USA
| | - Sergiusz Jóźwiak
- Department of Pediatric Neurology, Medical University of Warsaw, Warsaw, Poland.,Children's Memorial Health Institute, Warsaw, Poland
| | | | - Julian R Sampson
- Institute of Medical Genetics, Division of Cancer and Genetics, Cardiff University School of Medicine, Cardiff, UK
| | - Elizabeth A Thiele
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
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20
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Curatolo P, Moavero R, Roberto D, Graziola F. Genotype/Phenotype Correlations in Tuberous Sclerosis Complex. Semin Pediatr Neurol 2015; 22:259-73. [PMID: 26706013 DOI: 10.1016/j.spen.2015.10.002] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Tuberous sclerosis complex (TSC) is an autosomal dominant disorder characterized by the development of widespread hamartomatous lesions in various organs, including brain, skin, kidneys, heart, and eyes. Central nervous system is almost invariably involved, with up to 85% of patients presenting with epilepsy, and at least half of patients having intellectual disability or other neuropsychiatric disorders including autism spectrum disorder. TSC is caused by the mutation in one of the 2 genes TSC1, at 9q34, and TSC2, at 16p13.3. They respectively encode for hamartin and tuberin, which form an intracellular complex inhibiting the mammalian target of rapamycin. Mammalian target of rapamycin overactivation following the genetic defect determines the cell growth and proliferation responsible for TSC-related lesions, as well as the alterations in neuronal excitability and synaptogenesis leading to epilepsy and neuropsychiatric disorders. A causative mutation for the disorder is identified in about 85% of patients with a clinical diagnosis of TSC. Mosaicism and technology limits likely explain most of the no mutation identified cases. This review confirms that patients with TSC2 mutations considered as a group usually present a more severe phenotype, characterized by higher number of tubers, earlier age at seizure onset and higher prevalence of intellectual disability. However, the clinical phenotype of the disease presents a high variability, thus making the prediction of the phenotype on an individual basis still challenging. The increasing application of new molecular techniques to subjects with TSC has the potential to significantly reduce the rate of patients with no mutation demonstrated and to identify an increasing higher number of mutations. This would hopefully allow a better characterization of higher risk mutations, which might help clinicians to plan individualized surveillance plans. Furthermore, the increasing availability of disease registries to collect clinical and genetics data of patients help to define more valid and clinically oriented genotype or phenotype correlations.
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Affiliation(s)
- Paolo Curatolo
- (⁎)Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital of Rome, Rome, Italy.
| | - Romina Moavero
- (⁎)Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital of Rome, Rome, Italy; Child Neurology Unit, Department of Neuroscience and Neurorehabilitation, Bambino Gesù Children's Hospital, IRCCS, Rome, Italy
| | - Denis Roberto
- (⁎)Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital of Rome, Rome, Italy
| | - Federica Graziola
- (⁎)Child Neurology and Psychiatry Unit, Systems Medicine Department, Tor Vergata University Hospital of Rome, Rome, Italy
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21
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Vignoli A, La Briola F, Turner K, Scornavacca G, Chiesa V, Zambrelli E, Piazzini A, Savini MN, Alfano RM, Canevini MP. Epilepsy in TSC: certain etiology does not mean certain prognosis. Epilepsia 2013; 54:2134-42. [PMID: 24304436 DOI: 10.1111/epi.12430] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/20/2013] [Indexed: 01/03/2023]
Abstract
PURPOSE Prevalence and long-term outcome of epilepsy in tuberous sclerosis complex (TSC) is reported to be variable, and the reasons for this variability are still controversial. METHODS We reviewed the clinical characteristics of patients with TSC who were regularly followed since 2000 at the San Paolo Multidisciplinary Tuberous Sclerosis Centre in Milan, Italy. From patient charts we collected data about age at epilepsy onset, seizure frequency and seizure type, history of infantile spasms (IS), epileptic syndrome, evolution to refractory epilepsy or to seizure freedom and/or medication freedom, electroencephalography (EEG) features, magnetic resonance imaging (MRI) findings, cognitive outcome, and genetic background. KEY FINDINGS Among the 160 subjects (120 adults and 40 children), 116 (72.5%) had epilepsy: 57 (35.6%) were seizure-free, and 59 (36.9%) had drug-resistant epilepsy. Most seizure-free patients had a focal epilepsy (89.5%), with 54.4% of them drug resistant for a period of their lives. Epilepsy onset in the first year of life with IS and/or focal seizures was characteristic of the drug-resistant group of patients, as well as cognitive impairment and TSC2 mutation (p < 0.05). A small group of patients (7 patients, 4.4%) experienced a seizure only once; all of them had normal cognition. SIGNIFICANCE Although epilepsy management can be challenging in TSC, more than one third of patients had their seizures controlled: through monotherapy in 56% and by polytherapy in 32%. Moreover, 12% of the patients became seizure-free and were off medication. Identifying predictive features of epilepsy and cognitive outcome can ensure better management for patients with TSC and delineate genotype-phenotype correlations.
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Affiliation(s)
- Aglaia Vignoli
- Neurology Unit, Epilepsy Center - Neurology Unit 2, San Paolo Hospital, DISS University of Milan, Milan, Italy
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Clinical utility gene card for: tuberous sclerosis complex (TSC1, TSC2). Eur J Hum Genet 2013; 22:ejhg2013129. [PMID: 23756443 DOI: 10.1038/ejhg.2013.129] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
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Magri L, Cominelli M, Cambiaghi M, Cursi M, Leocani L, Minicucci F, Poliani PL, Galli R. Timing of mTOR activation affects tuberous sclerosis complex neuropathology in mouse models. Dis Model Mech 2013; 6:1185-97. [PMID: 23744272 PMCID: PMC3759338 DOI: 10.1242/dmm.012096] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Tuberous sclerosis complex (TSC) is a dominantly inherited disease with high penetrance and morbidity, and is caused by mutations in either of two genes, TSC1 or TSC2. Most affected individuals display severe neurological manifestations – such as intractable epilepsy, mental retardation and autism – that are intimately associated with peculiar CNS lesions known as cortical tubers (CTs). The existence of a significant genotype-phenotype correlation in individuals bearing mutations in either TSC1 or TSC2 is highly controversial. Similar to observations in humans, mouse modeling has suggested that a more severe phenotype is associated with mutation in Tsc2 rather than in Tsc1. However, in these mutant mice, deletion of either gene was achieved in differentiated astrocytes. Here, we report that loss of Tsc1 expression in undifferentiated radial glia cells (RGCs) early during development yields the same phenotype detected upon deletion of Tsc2 in the same cells. Indeed, the same aberrations in cortical cytoarchitecture, hippocampal disturbances and spontaneous epilepsy that have been detected in RGC-targeted Tsc2 mutants were observed in RGC-targeted Tsc1 mutant mice. Remarkably, thorough characterization of RGC-targeted Tsc1 mutants also highlighted subventricular zone (SVZ) disturbances as well as STAT3-dependent and -independent developmental-stage-specific defects in the differentiation potential of ex-vivo-derived embryonic and postnatal neural stem cells (NSCs). As such, deletion of either Tsc1 or Tsc2 induces mostly overlapping phenotypic neuropathological features when performed early during neurogenesis, thus suggesting that the timing of mTOR activation is a key event in proper neural development.
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Affiliation(s)
- Laura Magri
- Neural Stem Cell Biology Unit, Division of Regenerative Medicine, Stem Cells and Gene Therapy, San Raffaele Scientific Institute, Via Olgettina 58, Milan 20132, Italy
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