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Santos E, Clark C, Biag HMB, Tang SJ, Kim K, Ponzini MD, Schneider A, Giulivi C, Montanaro FAM, Gipe JTE, Dayton J, Randol JL, Yao PJ, Manolopoulos A, Kapogiannis D, Hwang YH, Hagerman P, Hagerman R, Tassone F. Open-Label Sulforaphane Trial in FMR1 Premutation Carriers with Fragile-X-Associated Tremor and Ataxia Syndrome (FXTAS). Cells 2023; 12:2773. [PMID: 38132093 PMCID: PMC10741398 DOI: 10.3390/cells12242773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Revised: 11/03/2023] [Accepted: 11/28/2023] [Indexed: 12/23/2023] Open
Abstract
Fragile X (FMR1) premutation is a common mutation that affects about 1 in 200 females and 1 in 450 males and can lead to the development of fragile-X-associated tremor/ataxia syndrome (FXTAS). Although there is no targeted, proven treatment for FXTAS, research suggests that sulforaphane, an antioxidant present in cruciferous vegetables, can enhance mitochondrial function and maintain redox balance in the dermal fibroblasts of individuals with FXTAS, potentially leading to improved cognitive function. In a 24-week open-label trial involving 15 adults aged 60-88 with FXTAS, 11 participants successfully completed the study, demonstrating the safety and tolerability of sulforaphane. Clinical outcomes and biomarkers were measured to elucidate the effects of sulforaphane. While there were nominal improvements in multiple clinical measures, they were not significantly different after correction for multiple comparisons. PBMC energetic measures showed that the level of citrate synthase was higher after sulforaphane treatment, resulting in lower ATP production. The ratio of complex I to complex II showed positive correlations with the MoCA and BDS scores. Several mitochondrial biomarkers showed increased activity and quantity and were correlated with clinical improvements.
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Affiliation(s)
- Ellery Santos
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Department of Pediatrics, School of Medicine, University of California, Davis, CA 95817, USA
| | - Courtney Clark
- Department of Pediatrics, School of Medicine, University of California, Davis, CA 95817, USA
| | - Hazel Maridith B. Biag
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Department of Pediatrics, School of Medicine, University of California, Davis, CA 95817, USA
| | - Si Jie Tang
- Department of Pediatrics, School of Medicine, University of California, Davis, CA 95817, USA
| | - Kyoungmi Kim
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, CA 95616, USA
| | - Matthew D. Ponzini
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Division of Biostatistics, Department of Public Health Sciences, University of California, Davis, CA 95616, USA
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Department of Pediatrics, School of Medicine, University of California, Davis, CA 95817, USA
| | - Cecilia Giulivi
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Federica Alice Maria Montanaro
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy;
- Department of Education, Psychology, Communication, University of Bari Aldo Moro, 70121 Bari, Italy
| | - Jesse Tran-Emilia Gipe
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Jacquelyn Dayton
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
| | - Jamie L. Randol
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, CA 95616, USA
| | - Pamela J. Yao
- Laboratory of Clinical Investigation, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 212241, USA (A.M.); (D.K.)
| | - Apostolos Manolopoulos
- Laboratory of Clinical Investigation, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 212241, USA (A.M.); (D.K.)
| | - Dimitrios Kapogiannis
- Laboratory of Clinical Investigation, Intramural Research Program, National Institute on Aging, National Institutes of Health, Baltimore, MD 212241, USA (A.M.); (D.K.)
| | - Ye Hyun Hwang
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, CA 95616, USA
| | - Paul Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, CA 95616, USA
| | - Randi Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Department of Pediatrics, School of Medicine, University of California, Davis, CA 95817, USA
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health, Sacramento, CA 95817, USA (A.S.); (R.H.)
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California, Davis, CA 95616, USA
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Tassone F, Protic D, Allen EG, Archibald AD, Baud A, Brown TW, Budimirovic DB, Cohen J, Dufour B, Eiges R, Elvassore N, Gabis LV, Grudzien SJ, Hall DA, Hessl D, Hogan A, Hunter JE, Jin P, Jiraanont P, Klusek J, Kooy RF, Kraan CM, Laterza C, Lee A, Lipworth K, Losh M, Loesch D, Lozano R, Mailick MR, Manolopoulos A, Martinez-Cerdeno V, McLennan Y, Miller RM, Montanaro FAM, Mosconi MW, Potter SN, Raspa M, Rivera SM, Shelly K, Todd PK, Tutak K, Wang JY, Wheeler A, Winarni TI, Zafarullah M, Hagerman RJ. Insight and Recommendations for Fragile X-Premutation-Associated Conditions from the Fifth International Conference on FMR1 Premutation. Cells 2023; 12:2330. [PMID: 37759552 PMCID: PMC10529056 DOI: 10.3390/cells12182330] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 09/09/2023] [Accepted: 09/12/2023] [Indexed: 09/29/2023] Open
Abstract
The premutation of the fragile X messenger ribonucleoprotein 1 (FMR1) gene is characterized by an expansion of the CGG trinucleotide repeats (55 to 200 CGGs) in the 5' untranslated region and increased levels of FMR1 mRNA. Molecular mechanisms leading to fragile X-premutation-associated conditions (FXPAC) include cotranscriptional R-loop formations, FMR1 mRNA toxicity through both RNA gelation into nuclear foci and sequestration of various CGG-repeat-binding proteins, and the repeat-associated non-AUG (RAN)-initiated translation of potentially toxic proteins. Such molecular mechanisms contribute to subsequent consequences, including mitochondrial dysfunction and neuronal death. Clinically, premutation carriers may exhibit a wide range of symptoms and phenotypes. Any of the problems associated with the premutation can appropriately be called FXPAC. Fragile X-associated tremor/ataxia syndrome (FXTAS), fragile X-associated primary ovarian insufficiency (FXPOI), and fragile X-associated neuropsychiatric disorders (FXAND) can fall under FXPAC. Understanding the molecular and clinical aspects of the premutation of the FMR1 gene is crucial for the accurate diagnosis, genetic counseling, and appropriate management of affected individuals and families. This paper summarizes all the known problems associated with the premutation and documents the presentations and discussions that occurred at the International Premutation Conference, which took place in New Zealand in 2023.
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Affiliation(s)
- Flora Tassone
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, CA 95817, USA;
- MIND Institute, University of California Davis, Davis, CA 95817, USA; (B.D.); (D.H.); (V.M.-C.)
| | - Dragana Protic
- Department of Pharmacology, Clinical Pharmacology and Toxicology, Faculty of Medicine, University of Belgrade, 11129 Belgrade, Serbia;
- Fragile X Clinic, Special Hospital for Cerebral Palsy and Developmental Neurology, 11040 Belgrade, Serbia
| | - Emily Graves Allen
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA; (E.G.A.); (P.J.); (K.S.)
| | - Alison D. Archibald
- Victorian Clinical Genetics Services, Royal Children’s Hospital, Melbourne, VIC 3052, Australia;
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, VIC 3052, Australia;
- Genomics in Society Group, Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, VIC 3052, Australia
| | - Anna Baud
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614 Poznan, Poland; (A.B.); (K.T.)
| | - Ted W. Brown
- Central Clinical School, University of Sydney, Sydney, NSW 2006, Australia;
- Fragile X Association of Australia, Brookvale, NSW 2100, Australia;
- NYS Institute for Basic Research in Developmental Disabilities, New York, NY 10314, USA
| | - Dejan B. Budimirovic
- Department of Psychiatry, Fragile X Clinic, Kennedy Krieger Institute, Baltimore, MD 21205, USA;
- Department of Psychiatry & Behavioral Sciences-Child Psychiatry, School of Medicine, Johns Hopkins University, Baltimore, MD 21205, USA
| | - Jonathan Cohen
- Fragile X Alliance Clinic, Melbourne, VIC 3161, Australia;
| | - Brett Dufour
- MIND Institute, University of California Davis, Davis, CA 95817, USA; (B.D.); (D.H.); (V.M.-C.)
- Department of Pathology and Laboratory Medicine, Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, School of Medicine, University of California Davis, Sacramento, CA 95817, USA;
| | - Rachel Eiges
- Stem Cell Research Laboratory, Medical Genetics Institute, Shaare Zedek Medical Center Affiliated with the Hebrew University School of Medicine, Jerusalem 91031, Israel;
| | - Nicola Elvassore
- Veneto Institute of Molecular Medicine (VIMM), 35129 Padova, Italy; (N.E.); (C.L.)
- Department of Industrial Engineering, University of Padova, 35131 Padova, Italy
| | - Lidia V. Gabis
- Keshet Autism Center Maccabi Wolfson, Holon 5822012, Israel;
- Faculty of Medicine, Tel-Aviv University, Tel Aviv 6997801, Israel
| | - Samantha J. Grudzien
- Department of Neurology, University of Michigan, 4148 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA; (S.J.G.); (P.K.T.)
- Neuroscience Graduate Program, University of Michigan, Ann Arbor, MI 48109, USA
- Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Deborah A. Hall
- Department of Neurological Sciences, Rush University, Chicago, IL 60612, USA;
| | - David Hessl
- MIND Institute, University of California Davis, Davis, CA 95817, USA; (B.D.); (D.H.); (V.M.-C.)
- Department of Psychiatry and Behavioral Sciences, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
| | - Abigail Hogan
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Columbia, SC 29208, USA; (A.H.); (J.K.)
| | - Jessica Ezzell Hunter
- RTI International, Research Triangle Park, NC 27709, USA; (J.E.H.); (S.N.P.); (M.R.); (A.W.)
| | - Peng Jin
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA; (E.G.A.); (P.J.); (K.S.)
| | - Poonnada Jiraanont
- Faculty of Medicine, King Mongkut’s Institute of Technology Ladkrabang, Bangkok 10520, Thailand;
| | - Jessica Klusek
- Department of Communication Sciences and Disorders, Arnold School of Public Health, University of South Carolina, Columbia, SC 29208, USA; (A.H.); (J.K.)
| | - R. Frank Kooy
- Department of Medical Genetics, University of Antwerp, 2000 Antwerp, Belgium;
| | - Claudine M. Kraan
- Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Melbourne, VIC 3052, Australia;
- Diagnosis and Development, Murdoch Children’s Research Institute, Melbourne, VIC 3052, Australia
| | - Cecilia Laterza
- Veneto Institute of Molecular Medicine (VIMM), 35129 Padova, Italy; (N.E.); (C.L.)
- Department of Industrial Engineering, University of Padova, 35131 Padova, Italy
| | - Andrea Lee
- Fragile X New Zealand, Nelson 7040, New Zealand;
| | - Karen Lipworth
- Fragile X Association of Australia, Brookvale, NSW 2100, Australia;
| | - Molly Losh
- Roxelyn and Richard Pepper Department of Communication Sciences and Disorders, Northwestern University, Evanston, IL 60201, USA;
| | - Danuta Loesch
- School of Psychology and Public Health, La Trobe University, Melbourne, VIC 3086, Australia;
| | - Reymundo Lozano
- Departments of Genetics and Genomic Sciences and Pediatrics, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA;
| | - Marsha R. Mailick
- Waisman Center, University of Wisconsin-Madison, Madison, WI 53705, USA;
| | - Apostolos Manolopoulos
- Intramural Research Program, Laboratory of Clinical Investigation, National Institute on Aging, Baltimore, MD 21224, USA;
| | - Veronica Martinez-Cerdeno
- MIND Institute, University of California Davis, Davis, CA 95817, USA; (B.D.); (D.H.); (V.M.-C.)
- Department of Pathology and Laboratory Medicine, Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, School of Medicine, University of California Davis, Sacramento, CA 95817, USA;
| | - Yingratana McLennan
- Department of Pathology and Laboratory Medicine, Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children of Northern California, School of Medicine, University of California Davis, Sacramento, CA 95817, USA;
| | | | - Federica Alice Maria Montanaro
- Child and Adolescent Neuropsychiatry Unit, Department of Neuroscience, Bambino Gesù Children’s Hospital, IRCCS, 00165 Rome, Italy;
- Department of Education, Psychology, Communication, University of Bari Aldo Moro, 70121 Bari, Italy
| | - Matthew W. Mosconi
- Schiefelbusch Institute for Life Span Studies, University of Kansas, Lawrence, KS 66045, USA;
- Clinical Child Psychology Program, University of Kansas, Lawrence, KS 66045, USA
- Kansas Center for Autism Research and Training (K-CART), University of Kansas, Lawrence, KS 66045, USA
| | - Sarah Nelson Potter
- RTI International, Research Triangle Park, NC 27709, USA; (J.E.H.); (S.N.P.); (M.R.); (A.W.)
| | - Melissa Raspa
- RTI International, Research Triangle Park, NC 27709, USA; (J.E.H.); (S.N.P.); (M.R.); (A.W.)
| | - Susan M. Rivera
- Department of Psychology, University of Maryland, College Park, MD 20742, USA;
| | - Katharine Shelly
- Department of Human Genetics, Emory University School of Medicine, Atlanta, GA 30322, USA; (E.G.A.); (P.J.); (K.S.)
| | - Peter K. Todd
- Department of Neurology, University of Michigan, 4148 BSRB, 109 Zina Pitcher Place, Ann Arbor, MI 48109, USA; (S.J.G.); (P.K.T.)
- Ann Arbor Veterans Administration Healthcare, Ann Arbor, MI 48105, USA
| | - Katarzyna Tutak
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Uniwersytetu Poznańskiego 6, 61-614 Poznan, Poland; (A.B.); (K.T.)
| | - Jun Yi Wang
- Center for Mind and Brain, University of California Davis, Davis, CA 95618, USA;
| | - Anne Wheeler
- RTI International, Research Triangle Park, NC 27709, USA; (J.E.H.); (S.N.P.); (M.R.); (A.W.)
| | - Tri Indah Winarni
- Center for Biomedical Research (CEBIOR), Faculty of Medicine, Universitas Diponegoro, Semarang 502754, Central Java, Indonesia;
| | - Marwa Zafarullah
- Department of Biochemistry and Molecular Medicine, School of Medicine, University of California Davis, Sacramento, CA 95817, USA;
| | - Randi J. Hagerman
- MIND Institute, University of California Davis, Davis, CA 95817, USA; (B.D.); (D.H.); (V.M.-C.)
- Department of Pediatrics, School of Medicine, University of California Davis, Sacramento, CA 95817, USA
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Giulivi C, Wang JY, Hagerman RJ. Artificial neural network applied to fragile X-associated tremor/ataxia syndrome stage diagnosis based on peripheral mitochondrial bioenergetics and brain imaging outcomes. Sci Rep 2022; 12:21382. [PMID: 36496525 PMCID: PMC9741636 DOI: 10.1038/s41598-022-25615-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 12/01/2022] [Indexed: 12/13/2022] Open
Abstract
No proven prognosis is available for the neurodegenerative disorder fragile X-associated tremor/ataxia syndrome (FXTAS). Artificial neural network analyses (ANN) were used to predict FXTAS progression using data from 127 adults (noncarriers and FMR1 premutation carriers with and without FXTAS) with five outcomes from brain MRI imaging and 22 peripheral bioenergetic outcomes from two cell types. Diagnosis accuracy by ANN predictions ranged from 41.7 to 86.3% (depending on the algorithm used), and those misclassified usually presented a higher FXTAS stage. ANN prediction of FXTAS stages was based on a combination of two imaging findings (white matter hyperintensity and whole-brain volumes adjusted for intracranial volume) and four bioenergetic outcomes. Those at Stage 3 vs. 0-2 showed lower mitochondrial mass, higher oxidative stress, and an altered electron transfer consistent with mitochondrial unfolded protein response activation. Those at Stages 4-5 vs. 3 had higher oxidative stress and glycerol-3-phosphate-linked ATP production, suggesting that targeting mGPDH activity may prevent a worse prognosis. This was confirmed by the bioenergetic improvement of inhibiting mGPDH with metformin in affected fibroblasts. ANN supports the prospect of an unbiased molecular definition in diagnosing FXTAS stages while identifying potential targets for personalized medicine.
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Affiliation(s)
- Cecilia Giulivi
- Department of Molecular Biosciences, School of Veterinary Medicine, University of California Davis, Davis, CA, USA.
- MIND Institute, University of California at Davis Medical Center, Sacramento, CA, USA.
| | - Jun Yi Wang
- MIND Institute, University of California at Davis Medical Center, Sacramento, CA, USA
- Center for Mind and Brain, University of California Davis, Davis, CA, USA
| | - Randi J Hagerman
- MIND Institute, University of California at Davis Medical Center, Sacramento, CA, USA
- Department of Pediatrics, University of California at Davis Medical Center, Sacramento, CA, USA
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Tosin MHS, Stebbins GT, Goetz CG, Hagerman RJ, Hessl D, Zolecki MA, Todd PK, Leehey MA, Hall DA. Fragile X-associated tremor ataxia syndrome rating scale: Revision and content validity using a mixed method approach. Front Neurol 2022; 13:977380. [PMID: 36188408 PMCID: PMC9515309 DOI: 10.3389/fneur.2022.977380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Accepted: 08/24/2022] [Indexed: 11/29/2022] Open
Abstract
Background The original Fragile X-associated Tremor Ataxia Syndrome Rating Scale (FXTAS-RS) contained 61 items, some requiring modifications to better meet recommendations for patient-focused rating scale development. Purpose Provide initial validation of a revised version of the FXTAS-RS for motor signs. Method We conducted a two-phase mixed-method approach. In Phase 1, revision, we implemented a Delphi technique identifying pertinent domains/subdomains and developing items through expert consensus. In Phase 2, content validation, we conducted cognitive pretesting assessing comprehensibility, comprehensiveness, and relevance of items to FXTAS motor signs. Results After five rounds of Delphi panel and two rounds of cognitive pretesting, the revised version of the FXTAS-RS was established with 18 items covering five domains and 13 subdomains of motor signs. Cognitive pretesting revealed adequate content validity for the assessment of FXTAS motor signs. Conclusion The revised FXTAS-RS has been successfully validated for content and it is now ready for large-scale field validation.
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Affiliation(s)
- Michelle H. S. Tosin
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, United States
| | - Glenn T. Stebbins
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, United States
| | - Christopher G. Goetz
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, United States
| | - Randi J. Hagerman
- Department of Pediatrics and the MIND Institute, University of California, Davis School of Medicine, Sacramento, CA, United States
| | - David Hessl
- Department of Psychiatry and Behavioral Sciences and the MIND Institute, University of California Davis School of Medicine, Sacramento, CA, United States
| | | | - Peter K. Todd
- University of Michigan, Ann Harbor, MI, United States
- Ann Arbor Veterans Administration Healthcare System, Ann Arbor, MI, United States
| | - Maureen A. Leehey
- University of Colorado School of Medicine, Aurora, CO, United States
| | - Deborah A. Hall
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, United States
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Zhang S, Shen L, Jiao B. Cognitive Dysfunction in Repeat Expansion Diseases: A Review. Front Aging Neurosci 2022; 14:841711. [PMID: 35478698 PMCID: PMC9036481 DOI: 10.3389/fnagi.2022.841711] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 02/24/2022] [Indexed: 11/16/2022] Open
Abstract
With the development of the sequencing technique, more than 40 repeat expansion diseases (REDs) have been identified during the past two decades. Moreover, the clinical features of these diseases show some commonality, and the nervous system, especially the cognitive function was affected in part by these diseases. However, the specific cognitive domains impaired in different diseases were inconsistent. Here, we survey literature on the cognitive consequences of the following disorders presenting cognitive dysfunction and summarizing the pathogenic genes, epidemiology, and different domains affected by these diseases. We found that the cognitive domains affected in neuronal intranuclear inclusion disease (NIID) were widespread including the executive function, memory, information processing speed, attention, visuospatial function, and language. Patients with C9ORF72-frontotemporal dementia (FTD) showed impairment in executive function, memory, language, and visuospatial function. While in Huntington's disease (HD), the executive function, memory, and information processing speed were affected, in the fragile X-associated tremor/ataxia syndrome (FXTAS), executive function, memory, information processing speed, and attention were impaired. Moreover, the spinocerebellar ataxias showed broad damage in almost all the cognitive domains except for the relatively intact language ability. Some other diseases with relatively rare clinical data also indicated cognitive dysfunction, such as myotonic dystrophy type 1 (DM1), progressive myoclonus epilepsy (PME), Friedreich ataxia (FRDA), Huntington disease like-2 (HDL2), and cerebellar ataxia, neuropathy, vestibular areflexia syndrome (CANVAS). We drew a cognitive function landscape of the related REDs that might provide an aspect for differential diagnosis through cognitive domains and effective non-specific interventions for these diseases.
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Affiliation(s)
- Sizhe Zhang
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
| | - Lu Shen
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, China
- Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, China
- Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
| | - Bin Jiao
- Department of Neurology, Xiangya Hospital, Central South University, Changsha, China
- National Clinical Research Center for Geriatric Disorders, Central South University, Changsha, China
- Engineering Research Center of Hunan Province in Cognitive Impairment Disorders, Central South University, Changsha, China
- Hunan International Scientific and Technological Cooperation Base of Neurodegenerative and Neurogenetic Diseases, Changsha, China
- Key Laboratory of Hunan Province in Neurodegenerative Disorders, Central South University, Changsha, China
- *Correspondence: Bin Jiao
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Frequency of FMR1 Premutation Alleles in Patients with Undiagnosed Cerebellar Ataxia and Multiple System Atrophy in the Japanese Population. CEREBELLUM (LONDON, ENGLAND) 2021; 21:954-962. [PMID: 34845661 DOI: 10.1007/s12311-021-01329-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 09/26/2021] [Indexed: 10/19/2022]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is an adult-onset neurodegenerative disorder caused by FMR1 premutation expansion of CGG repeats. FXTAS can be misdiagnosed with many neurodegenerative disorders manifesting with cerebellar ataxias owing to their overlapping clinical and radiological features. The frequency of the FMR1 premutation allele in Japan has not been fully determined. Herein, we aimed to determine the frequency of FMR1 premutation alleles in Japanese patients with undiagnosed cerebellar ataxia and multiple system atrophy, using repeat-primed PCR in 186 patients with adult onset of undiagnosed cerebellar ataxia and 668 patients with multiple system atrophy, to identify expanded CGG repeats as well as to detect AGG interruptions within the expanded alleles. The size of expansions was estimated using fragment length analysis of PCR products obtained by conventional PCR employing a pair of unique primers flanking the repeat sequence. We identified FMR1 premutation alleles in three male patients. One patient revealed 84 repeat units with one AGG interruption and another patient showed 103 repeat units. Both had presented with sporadic cerebellar ataxia, giving an estimated frequency of 3.7% among Japanese male patients with sporadic cerebellar ataxia with age at onset above 50 years. One patient with the clinical diagnosis of multiple system atrophy harbored 60 repeat units with four AGG interruptions. FMR1 intermediate alleles were observed in two males and one female among the multiple system atrophy patients. We found that genetic tests for FMR1 premutation should be considered in Japanese male patients with cerebellar ataxia with the age at onset above 50 years.
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Gläser D, Deutsche Gesellschaft Für Humangenetik E V, Berufsverband Deutscher Humangenetiker E V, Hinderhofer K. Leitlinien zur molekulargenetischen Diagnostik: Fragiles-X-Syndrom und andere FMR1-assoziierte Syndrome. MED GENET-BERLIN 2021; 33:65-73. [PMID: 38836214 PMCID: PMC11006362 DOI: 10.1515/medgen-2021-2059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Affiliation(s)
- Dieter Gläser
- Genetikum, Wegenerstr. 15, D-89231Neu-Ulm, Deutschland
| | - Deutsche Gesellschaft Für Humangenetik E V
- Genetikum, Wegenerstr. 15, D-89231Neu-Ulm, Deutschland
- Universitätsklinikum Heidelberg, Institut für Humangenetik, Im Neuenheimer Feld 366, D-69120Heidelberg, Deutschland
| | - Berufsverband Deutscher Humangenetiker E V
- Genetikum, Wegenerstr. 15, D-89231Neu-Ulm, Deutschland
- Universitätsklinikum Heidelberg, Institut für Humangenetik, Im Neuenheimer Feld 366, D-69120Heidelberg, Deutschland
| | - Katrin Hinderhofer
- Universitätsklinikum Heidelberg, Institut für Humangenetik, Im Neuenheimer Feld 366, D-69120Heidelberg, Deutschland
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8
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Li J, Kim S, Pappas SS, Dauer WT. CNS critical periods: implications for dystonia and other neurodevelopmental disorders. JCI Insight 2021; 6:142483. [PMID: 33616084 PMCID: PMC7934928 DOI: 10.1172/jci.insight.142483] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Critical periods are discrete developmental stages when the nervous system is especially sensitive to stimuli that facilitate circuit maturation. The distinctive landscapes assumed by the developing CNS create analogous periods of susceptibility to pathogenic insults and responsiveness to therapy. Here, we review critical periods in nervous system development and disease, with an emphasis on the neurodevelopmental disorder DYT1 dystonia. We highlight clinical and laboratory observations supporting the existence of a critical period during which the DYT1 mutation is uniquely harmful, and the implications for future therapeutic development.
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Affiliation(s)
- Jay Li
- Medical Scientist Training Program, University of Michigan, Ann Arbor, Michigan, USA
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Sumin Kim
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, Michigan, USA
| | | | - William T. Dauer
- Peter O’Donnell Jr. Brain Institute
- Department of Neurology, and
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, Texas, USA
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9
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Holm KN, Herren AW, Taylor SL, Randol JL, Kim K, Espinal G, Martiínez-Cerdeño V, Pessah IN, Hagerman RJ, Hagerman PJ. Human Cerebral Cortex Proteome of Fragile X-Associated Tremor/Ataxia Syndrome. Front Mol Biosci 2021; 7:600840. [PMID: 33585555 PMCID: PMC7879451 DOI: 10.3389/fmolb.2020.600840] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/27/2020] [Indexed: 01/10/2023] Open
Abstract
Background: Fragile X-associated tremor/ataxia syndrome (FXTAS) is an adult-onset neurodegenerative disorder associated with premutation CGG-repeat expansions (55–200 repeats) in the 5′ non-coding portion of the fragile X mental retardation 1 (FMR1) gene. Core features of FXTAS include progressive tremor/ataxia, cognitive decline, variable brain volume loss, and white matter disease. The principal histopathological feature of FXTAS is the presence of central nervous system (CNS) and non-CNS intranuclear inclusions. Objective: To further elucidate the molecular underpinnings of FXTAS through the proteomic characterization of human FXTAS cortexes. Results: Proteomic analysis of FXTAS brain cortical tissue (n = 8) identified minor differences in protein abundance compared to control brains (n = 6). Significant differences in FXTAS relative to control brain predominantly involved decreased abundance of proteins, with the greatest decreases observed for tenascin-C (TNC), cluster of differentiation 38 (CD38), and phosphoserine aminotransferase 1 (PSAT1); proteins typically increased in other neurodegenerative diseases. Proteins with the greatest increased abundance include potentially novel neurodegeneration-related proteins and small ubiquitin-like modifier 1/2 (SUMO1/2). The FMRpolyG peptide, proposed in models of FXTAS pathogenesis but only identified in trace amounts in the earlier study of FXTAS inclusions, was not identified in any of the FXTAS or control brains in the current study. Discussion: The observed proteomic shifts, while generally relatively modest, do show a bias toward decreased protein abundance with FXTAS. Such shifts in protein abundance also suggest altered RNA binding as well as loss of cell–cell adhesion/structural integrity. Unlike other neurodegenerative diseases, the proteome of end-stage FXTAS does not suggest a strong inflammation-mediated degenerative response.
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Affiliation(s)
- Katharine Nichole Holm
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Davis, CA, United States
| | - Anthony W Herren
- Mass Spectrometry Research Core, University of California Davis, Davis, CA, United States
| | - Sandra L Taylor
- Department of Public Health Sciences, Division of Biostatistics, University of California Davis School of Medicine, Davis, CA, United States
| | - Jamie L Randol
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Davis, CA, United States
| | - Kyoungmi Kim
- Department of Public Health Sciences, Division of Biostatistics, University of California Davis School of Medicine, Davis, CA, United States.,Medical Investigation of Neurodevelopmental Disorders Institute, University of California Davis School of Medicine, Davis, CA, United States
| | - Glenda Espinal
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Davis, CA, United States
| | - Verónica Martiínez-Cerdeño
- Medical Investigation of Neurodevelopmental Disorders Institute, University of California Davis School of Medicine, Davis, CA, United States.,Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Davis, CA, United States
| | - Isaac N Pessah
- Medical Investigation of Neurodevelopmental Disorders Institute, University of California Davis School of Medicine, Davis, CA, United States.,Department of Molecular Biosciences, University of California Davis School of Veterinary Medicine, Davis, CA, United States
| | - Randi J Hagerman
- Medical Investigation of Neurodevelopmental Disorders Institute, University of California Davis School of Medicine, Davis, CA, United States.,Department of Pediatrics, University of California Davis School of Medicine, Davis, CA, United States
| | - Paul J Hagerman
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Davis, CA, United States.,Medical Investigation of Neurodevelopmental Disorders Institute, University of California Davis School of Medicine, Davis, CA, United States
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10
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Schneider A, Summers S, Tassone F, Seritan A, Hessl D, Hagerman P, Hagerman R. Women with Fragile X-associated Tremor/Ataxia Syndrome. Mov Disord Clin Pract 2020; 7:910-919. [PMID: 33163562 PMCID: PMC7604678 DOI: 10.1002/mdc3.13084] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 06/16/2020] [Accepted: 08/03/2020] [Indexed: 12/17/2022] Open
Abstract
BACKGROUND Fragile X-associated tremor and ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder linked to the FMR1 premutation. OBJECTIVES FXTAS in women is far less common than in men, and this study represents the largest sample reported to date. METHODS A total of 53 female premutation carriers with FXTAS (meanage, 66.83 years; FXTAS stages 2-5) and 55 age-matched and demographic background-matched control participants (meanage, 61.94 years) underwent a comprehensive molecular, physiological, neuropsychological, and psychiatric assessment. RESULTS The large sample of female premutation carriers showed a wide range of variability of clinical signs and symptom progression. The imaging results showed a middle cerebellar peduncles sign in only 6 patients; another symptom included high-signal intensity in the splenium of the corpus callosum, and diffuse cerebral deep white matter changes (e.g., in the pons) are more common. The rate of psychiatric disorders, especially depression, is higher than in the general population. There is a clear impairment in executive functioning and fine motor skills in connection with a higher FXTAS stage. CONCLUSIONS The manifestation of FXTAS symptoms in female carriers can be diverse with a milder phenotype and a lower penetrance than those observed in male premutation carriers. The middle cerebellar peduncles sign is present in only a small percentage of the sample, and we propose that the imaging criteria for FXTAS in women need to be expanded.
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Affiliation(s)
- Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders InstituteSacramentoCaliforniaUSA
- Department of Pediatrics, School of MedicineUniversity of California–Davis, Medical CenterSacramentoCaliforniaUSA
| | - Scott Summers
- Department of Psychiatry and Behavioral SciencesUniversity of California–Davis, Medical CenterSacramentoCaliforniaUSA
| | - Flora Tassone
- Department of BiochemistryUniversity of California–Davis, Medical CenterSacramentoCaliforniaUSA
| | - Andreea Seritan
- Department of Psychiatry, UCSF Weill Institute for NeurosciencesUniversity of CaliforniaSan FranciscoCaliforniaUSA
| | - David Hessl
- Medical Investigation of Neurodevelopmental Disorders InstituteSacramentoCaliforniaUSA
- Department of Psychiatry and Behavioral SciencesUniversity of California–Davis, Medical CenterSacramentoCaliforniaUSA
| | - Paul Hagerman
- Department of BiochemistryUniversity of California–Davis, Medical CenterSacramentoCaliforniaUSA
| | - Randi Hagerman
- Medical Investigation of Neurodevelopmental Disorders InstituteSacramentoCaliforniaUSA
- Department of Pediatrics, School of MedicineUniversity of California–Davis, Medical CenterSacramentoCaliforniaUSA
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11
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O'Keefe JA, Bang D, Robertson EE, Biskis A, Ouyang B, Liu Y, Pal G, Berry‐Kravis E, Hall DA. Prodromal Markers of Upper Limb Deficits in FMR1 Premutation Carriers and Quantitative Outcome Measures for Future Clinical Trials in Fragile X-associated Tremor/Ataxia Syndrome. Mov Disord Clin Pract 2020; 7:810-819. [PMID: 33043077 PMCID: PMC7533995 DOI: 10.1002/mdc3.13045] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/09/2020] [Accepted: 07/13/2020] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) is a rare, late-onset neurodegenerative disorder characterized by tremor and cerebellar gait ataxia, affecting premutation carriers (PMC) of CGG expansions (range, 55-200) in the fragile X mental retardation 1 (FMR1) gene. Discovery of early predictors for FXTAS and quantitative characterization of motor deficits are critical for identifying disease onset, monitoring disease progression, and determining efficacy of interventions. METHODS A total of 39 PMC with FXTAS, 20 PMC without FXTAS, and 27 healthy controls performed a series of upper extremity (UE) motor tasks assessing tremor, bradykinesia, and rapid alternating movements that were quantified using an inertial-based sensor system (Kinesia One; Great Lakes NeuroTechnologies, Cleveland, OH, USA). Sub-scores from the clinician-rated FXTAS Rating Scale were correlated with the severity scores generated by the sensor system to determine its validity in FXTAS. RESULTS PMC with FXTAS had significantly worse postural and kinetic tremor compared with PMC without FXTAS (P = 0.02, 0.03) and controls (P = 0.001, 0.0001), respectively, and slower finger tap (P = 0.001), hand movement (P = 0.0001), and rapid alternating movement speed (P = 0.003) and amplitude (P = 0.04) than controls. PMC without FXTAS had significantly worse right finger tap (P = 0.004), hand movement (P = 0.01), and rapid alternating movement speed (P = 0.003) and amplitude (P = 0.02) than controls. FXTAS Rating Scale subscores significantly correlated with all tremorography scores except for finger taps and left rapid alternating movement. CONCLUSIONS These findings support the use of inertial sensor quantification systems as promising measures for preclinical FXTAS symptom detection in PMC, characterization of the natural history of FXTAS, assessment of medication responses, and outcome assessment in clinical trials.
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Affiliation(s)
- Joan A. O'Keefe
- Department of Cell & Molecular MedicineRush University Medical CenterChicagoIllinoisUSA
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
| | - Deborah Bang
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
| | - Erin E. Robertson
- Department of Cell & Molecular MedicineRush University Medical CenterChicagoIllinoisUSA
| | - Alexandras Biskis
- Department of Cell & Molecular MedicineRush University Medical CenterChicagoIllinoisUSA
- Department of PediatricsRush University Medical CenterChicagoIllinoisUSA
| | - Bichun Ouyang
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
| | - Yuanqing Liu
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
| | - Gian Pal
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
| | - Elizabeth Berry‐Kravis
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
- Department of BiochemistryRush University Medical CenterChicagoIllinoisUSA
| | - Deborah A. Hall
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
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12
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Elevated FMR1-mRNA and lowered FMRP - A double-hit mechanism for psychiatric features in men with FMR1 premutations. Transl Psychiatry 2020; 10:205. [PMID: 32576818 PMCID: PMC7311546 DOI: 10.1038/s41398-020-00863-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Revised: 05/19/2020] [Accepted: 05/22/2020] [Indexed: 01/07/2023] Open
Abstract
Fragile X syndrome (FXS) is caused by a full mutation of the FMR1 gene (>200 CGG repeats and subsequent methylation), such that there is little or no FMR1 protein (FMRP) produced, leading to intellectual disability (ID). Individuals with the premutation allele (55-200 CGG repeats, generally unmethylated) have elevated FMR1 mRNA levels, a consequence of enhanced transcription, resulting in neuronal toxicity and a spectrum of premutation-associated disorders, including the neurodegenerative disorder fragile X-associated tremor/ataxia syndrome (FXTAS). Here we described 14 patients who had both lowered FMRP and elevated FMR1 mRNA levels, representing dual mechanisms of clinical involvement, which may combine features of both FXS and FXTAS. In addition, the majority of these cases show psychiatric symptoms, including bipolar disorder, and/or psychotic features, which are rarely seen in those with just FXS.
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13
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Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS): Pathophysiology and Clinical Implications. Int J Mol Sci 2020; 21:ijms21124391. [PMID: 32575683 PMCID: PMC7352421 DOI: 10.3390/ijms21124391] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 05/23/2020] [Accepted: 05/28/2020] [Indexed: 02/06/2023] Open
Abstract
The fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder seen in older premutation (55-200 CGG repeats) carriers of FMR1. The premutation has excessive levels of FMR1 mRNA that lead to toxicity and mitochondrial dysfunction. The clinical features usually begin in the 60 s with an action or intention tremor followed by cerebellar ataxia, although 20% have only ataxia. MRI features include brain atrophy and white matter disease, especially in the middle cerebellar peduncles, periventricular areas, and splenium of the corpus callosum. Neurocognitive problems include memory and executive function deficits, although 50% of males can develop dementia. Females can be less affected by FXTAS because of a second X chromosome that does not carry the premutation. Approximately 40% of males and 16% of female carriers develop FXTAS. Since the premutation can occur in less than 1 in 200 women and 1 in 400 men, the FXTAS diagnosis should be considered in patients that present with tremor, ataxia, parkinsonian symptoms, neuropathy, and psychiatric problems. If a family history of a fragile X mutation is known, then FMR1 DNA testing is essential in patients with these symptoms.
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14
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Salcedo-Arellano MJ, Cabal-Herrera AM, Tassanakijpanich N, McLennan YA, Hagerman RJ. Ataxia as the Major Manifestation of Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS): Case Series. Biomedicines 2020; 8:E136. [PMID: 32466255 PMCID: PMC7277845 DOI: 10.3390/biomedicines8050136] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Revised: 05/20/2020] [Accepted: 05/21/2020] [Indexed: 11/30/2022] Open
Abstract
Fragile X-associated tremor and ataxia syndrome (FXTAS) is a neurodegenerative disease developed by carriers of a premutation in the fragile X mental retardation 1 (FMR1) gene. The core clinical symptoms usually manifest in the early 60s, typically beginning with intention tremor followed by cerebellar ataxia. Ataxia can be the only symptom in approximately 20% of the patients. FXTAS has a slow progression, and patients usually experience advanced deterioration 15 to 25 years after the initial diagnosis. Common findings in brain imaging include substantial brain atrophy and white matter disease (WMD). We report three cases with an atypical clinical presentation, all presenting with gait problems as their initial manifestation and with ataxia as the dominant symptom without significant tremor, as well as a faster than usual clinical progression. Magnetic resonance imaging (MRI) was remarkable for severe brain atrophy, ventriculomegaly, thinning of the corpus callosum, and periventricular WMD. Two cases were diagnosed with definite FXTAS on the basis of clinical and radiological findings, with one individual also developing moderate dementia. Factors such as environmental exposure and general anesthesia could have contributed to their clinical deterioration. FXTAS should be considered in the differential diagnosis of patients presenting with ataxia, even in the absence of tremor, and FMR1 DNA testing should be sought in those with a family history of fragile X syndrome or premutation disorders.
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Affiliation(s)
- Maria Jimena Salcedo-Arellano
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA 95817, USA; (M.J.S.-A.); (Y.A.M.)
- MIND Institute, University of California Davis, Sacramento, CA 95817, USA; (A.M.C.-H.); (N.T.)
| | - Ana Maria Cabal-Herrera
- MIND Institute, University of California Davis, Sacramento, CA 95817, USA; (A.M.C.-H.); (N.T.)
- Group on Congenital Malformations and Dysmorphology (MACOS), Faculty of Health, Universidad del Valle, Cali, Valle del Cauca 760041, Colombia
| | - Nattaporn Tassanakijpanich
- MIND Institute, University of California Davis, Sacramento, CA 95817, USA; (A.M.C.-H.); (N.T.)
- Department of Pediatrics, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
| | - Yingratana A. McLennan
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA 95817, USA; (M.J.S.-A.); (Y.A.M.)
- MIND Institute, University of California Davis, Sacramento, CA 95817, USA; (A.M.C.-H.); (N.T.)
| | - Randi J. Hagerman
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA 95817, USA; (M.J.S.-A.); (Y.A.M.)
- MIND Institute, University of California Davis, Sacramento, CA 95817, USA; (A.M.C.-H.); (N.T.)
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15
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Hill EJ, Goetz CG, Stebbins GT, Hagerman R, Ouyang B, Hall DA. Placebo Response in Fragile X-associated Tremor/Ataxia Syndrome. Mov Disord Clin Pract 2020; 7:298-302. [PMID: 32258228 PMCID: PMC7111569 DOI: 10.1002/mdc3.12919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 02/17/2020] [Accepted: 02/20/2020] [Indexed: 11/08/2022] Open
Abstract
BACKGROUND Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder characterized by intention tremor, cerebellar ataxia, and executive dysfunction in carriers of a CGG repeat expansion premutation (55-200 repeats) in the fragile X mental retardation 1 (FMR1) gene. Given reports of poor insight in FXTAS, we postulated that patients with FXTAS would be less likely to exhibit placebo response. OBJECTIVE To analyze placebo response from the first randomized controlled trial in FXTAS that evaluated cognitive and motor outcomes after 1 year of treatment with memantine. METHODS Data from the placebo arm of the first randomized controlled trial in FXTAS were analyzed. There were 2 coprimary outcomes. Based on studies in Parkinson's disease, placebo responders were defined as individuals with an improvement of at least 50% in the coprimary outcomes. Improvements of 20% and 30% served as secondary cutoff values based on the suggested magnitude of placebo response in other movement disorders. RESULTS A total of 36 participants in the placebo group completed baseline and follow-up evaluations. The average age was 66 ± 7 years, and 60% were men. Average CGG repeat size was 86 ± 18. A total of 19 participants had stage 3 disease. Only 1 patient showed 50% improvement in both coprimary outcomes. At 30% and 20% improvement, there were 2 and 3 patients showing placebo response in the coprimary outcomes, respectively. CONCLUSIONS Patients with FXTAS exhibited low rates of placebo response in a randomized controlled trial. Further studies on the relationship between baseline insight and placebo responsivity are applicable to FXTAS and other disorders exhibiting cognitive impairment.
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Affiliation(s)
- Emily J. Hill
- Department of NeurologyBaylor College of MedicineHoustonTexasUSA
| | - Christopher G. Goetz
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
| | - Glenn T. Stebbins
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
| | - Randi Hagerman
- University of California Davis Medical Investigation of Neurodevelopmental Disorders (MIND) InstituteSacramentoCaliforniaUSA
- Department of PediatricsUniversity of California Davis Medical CenterSacramentoCaliforniaUSA
| | - Bichun Ouyang
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
| | - Deborah A. Hall
- Department of Neurological SciencesRush University Medical CenterChicagoIllinoisUSA
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16
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Aydin EY, Schneider A, Protic D, Wang JY, Martínez-Cerdeño V, Tassone F, Tang HT, Perlman S, Hagerman RJ. Rapidly Progressing Neurocognitive Disorder in a Male with FXTAS and Alzheimer's Disease. Clin Interv Aging 2020; 15:285-292. [PMID: 32161452 PMCID: PMC7051898 DOI: 10.2147/cia.s240314] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2019] [Accepted: 01/09/2020] [Indexed: 11/29/2022] Open
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder that usually begins in the early 60s and affects carriers of premutation expansion (55-200 CGG repeats) of the fragile X mental retardation 1 (FMR1) gene. Additional disorders can co-occur with FXTAS including Alzheimer's disease (AD). Here we discuss a case report of a male with 67 CGG repeats in FMR1 who had mild late-onset FXTAS symptoms followed by neurocognitive disorder symptoms consistent with AD. The patient has developed tremor and ataxia that are the two characteristic symptoms of FXTAS. In addition, he shows rapid cognitive decline, brain atrophy most substantial in the medial temporal lobe, and decreased metabolism in the brain regions that are the characteristic findings of AD. The purpose of this study is to describe a patient profile with both diseases and review the details of an overlap between these two diseases.
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Affiliation(s)
- Elber Yuksel Aydin
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA
- Istanbul Faculty of Medicine, Istanbul University, Istanbul, Turkey
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, USA
| | - Dragana Protic
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA
- Department of Pharmacology, Clinical Pharmacology and Toxicology, School of Medicine, University of Belgrade, Belgrade, Serbia
| | - Jun Yi Wang
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA
- Center for Mind and Brain, University of California Davis School of Medicine, Sacramento, CA, USA
| | - Veronica Martínez-Cerdeño
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA
- Department of Pathology and Laboratory Medicine, Institute for Pediatric Regenerative Medicine, University of California Davis School of Medicine and Shriners Hospital, Sacramento, CA, USA
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Sacramento, CA, USA
| | - Hiu-Tung Tang
- Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Sacramento, CA, USA
| | - Susan Perlman
- Department of Neurology, University of California Los Angeles School of Medicine, Los Angeles, CA, USA
| | - Randi J Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis, Sacramento, CA, USA
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, USA
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17
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Suardi GAM, Haddad LA. FMRP ribonucleoprotein complexes and RNA homeostasis. ADVANCES IN GENETICS 2020; 105:95-136. [PMID: 32560791 DOI: 10.1016/bs.adgen.2020.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The Fragile Mental Retardation 1 gene (FMR1), at Xq27.3, encodes the fragile mental retardation protein (FMRP), and displays in its 5'-untranslated region a series of polymorphic CGG triplet repeats that may undergo dynamic mutation. Fragile X syndrome (FXS) is the leading cause of inherited intellectual disability among men, and is most frequently due to FMR1 full mutation and consequent transcription repression. FMR1 premutations may associate with at least two other clinical conditions, named fragile X-associated primary ovarian insufficiency (FXPOI) and tremor and ataxia syndrome (FXTAS). While FXPOI and FXTAS appear to be mediated by FMR1 mRNA accumulation, relative reduction of FMRP, and triplet repeat translation, FXS is due to the lack of the RNA-binding protein FMRP. Besides its function as mRNA translation repressor in neuronal and stem/progenitor cells, RNA editing roles have been assigned to FMRP. In this review, we provide a brief description of FMR1 transcribed microsatellite and associated clinical disorders, and discuss FMRP molecular roles in ribonucleoprotein complex assembly and trafficking, as well as aspects of RNA homeostasis affected in FXS cells.
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Affiliation(s)
- Gabriela Aparecida Marcondes Suardi
- Human Genome and Stem Cell Research Center, Department of Genetics and Evolutionary Biology, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil
| | - Luciana Amaral Haddad
- Human Genome and Stem Cell Research Center, Department of Genetics and Evolutionary Biology, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.
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18
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Lenka A, Louis ED. Revisiting the Clinical Phenomenology of "Cerebellar Tremor": Beyond the Intention Tremor. THE CEREBELLUM 2019; 18:565-574. [PMID: 30565088 DOI: 10.1007/s12311-018-0994-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Tremor is an involuntary, rhythmic, oscillatory movement of a body part. It is a central feature of a range of diseases resulting from pathological changes in the cerebellum. Interestingly, in modern times, the terms "cerebellar tremor" and "intention tremor" are often used synonymously and interchangeably. However, "cerebellar tremor" (i.e., tremors of cerebellar origin) do not always present exclusively as intention tremor. In this article, we comprehensively revisit the clinical phenomenology of tremors observed in various diseases that are based in the cerebellum. By this, we mean diseases for which the cerebellum and its various connections are often seen as playing a central and defining role. These include spinocerebellar ataxias, essential tremor, orthostatic tremor, dystonia, acute cerebellitis, cerebellar tumors, paraneoplastic cerebellar degeneration, and cerebellar strokes. The theme of this article is to highlight, through published data available in the current literature, that the clinical phenomenology of tremor of cerebellar origin is heterogeneous, and it extends beyond that of intention tremor to include postural tremors, kinetic tremor, rest tremor, and orthostatic tremor. This heterogeneity is consistent with the seminal work of Gordon Holmes, in which he described a variety of tremors aside from intention tremor in the setting of cerebellar lesions. In the end, it would seem that the notion that intention tremor is the sole signature of cerebellar lesions is an over-simplification and is not correct. Future studies are warranted to identify and further characterize the heterogeneity of tremors arising from the various cerebellar etiologies.
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Affiliation(s)
- Abhishek Lenka
- Department of Neurology, MedStar Georgetown University Hospital, Washington, DC, USA
| | - Elan D Louis
- Division of Movement Disorders, Department of Neurology, Yale School of Medicine, Yale University, New Haven, CT, USA. .,Department of Chronic Disease Epidemiology, Yale School of Public Health, Yale University, New Haven, CT, USA. .,Department of Neurology, Center for Neuroepidemiology and Clinical Neurological Research, Yale School of Medicine, Yale University, 15 York Street, PO Box 208018, New Haven, CT, 06520-8018, USA.
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19
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McKinney WS, Wang Z, Kelly S, Khemani P, Lui S, White SP, Mosconi MW. Precision Sensorimotor Control in Aging FMR1 Gene Premutation Carriers. Front Integr Neurosci 2019; 13:56. [PMID: 31632248 PMCID: PMC6783559 DOI: 10.3389/fnint.2019.00056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Accepted: 09/18/2019] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Individuals with premutation alleles of the FMR1 gene are at risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative condition affecting sensorimotor function. Information on quantitative symptom traits associated with aging in premutation carriers is needed to clarify neurodegenerative processes contributing to FXTAS. MATERIALS AND METHODS 26 FMR1 premutation carriers ages 44-77 years and 31 age-matched healthy controls completed rapid (2 s) and sustained (8 s) visually guided precision gripping tasks. Individuals pressed at multiple force levels to determine the impact of increasing the difficulty of sensorimotor actions on precision behavior. During initial pressing, reaction time, the rate at which individuals increased their force, the duration of pressing, and force accuracy were measured. During sustained gripping, the complexity of the force time series, force variability, and mean force were examined. During relaxation, the rate at which individuals decreased their force was measured. We also examined the relationships between visuomotor behavior and cytosine-guanine-guanine (CGG) repeat length and clinically rated FXTAS symptoms. RESULTS Relative to controls, premutation carriers showed reduced rates of initial force generation during rapid motor actions and longer durations of their initial pressing with their dominant hand. During sustained force, premutation carriers demonstrated reduced force complexity, though this effect was specific to younger premutation carries during dominant hand pressing and was more severe for younger relative to older premutation carriers at low and medium force levels. Increased reaction time and lower sustained force complexity each were associated with greater CGG repeat length for premutation carriers. Increased reaction time and increased sustained force variability were associated with more severe clinically rated FXTAS symptoms. CONCLUSION Overall our findings suggest multiple sensorimotor processes are disrupted in aging premutation carriers, including initial force control guided by feedforward mechanisms and sustained sensorimotor behaviors guided by sensory feedback control processes. Results indicating that sensorimotor issues in aging premutation carriers relate to both greater CGG repeat length and clinically rated FXTAS symptoms suggest that quantitative tests of precision sensorimotor ability may serve as key targets for monitoring FXTAS risk and progression.
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Affiliation(s)
- Walker S. McKinney
- Clinical Child Psychology Program, Life Span Institute and Kansas Center for Autism Research and Training (K-CART), University of Kansas, Lawrence, KS, United States
| | - Zheng Wang
- Department of Occupational Therapy, University of Florida, Gainesville, FL, United States
| | - Shannon Kelly
- Clinical Child Psychology Program, Life Span Institute and Kansas Center for Autism Research and Training (K-CART), University of Kansas, Lawrence, KS, United States
| | - Pravin Khemani
- Department of Neurology, Swedish Neuroscience Institute, Seattle, WA, United States
| | - Su Lui
- Department of Radiology, Huaxi Magnetic Resonance Research Center, West China Hospital of Sichuan University, Chengdu, China
| | - Stormi P. White
- Department of Pediatrics, Marcus Autism Center, Emory University School of Medicine, Atlanta, GA, United States
| | - Matthew W. Mosconi
- Clinical Child Psychology Program, Life Span Institute and Kansas Center for Autism Research and Training (K-CART), University of Kansas, Lawrence, KS, United States
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Fay-Karmon T, Hassin-Baer S. The spectrum of tremor among carriers of the FMR1 premutation with or without the fragile X-associated tremor/ataxia syndrome (FXTAS). Parkinsonism Relat Disord 2019; 65:32-38. [DOI: 10.1016/j.parkreldis.2019.05.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 05/01/2019] [Accepted: 05/06/2019] [Indexed: 10/26/2022]
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Mishra SK, Khosa S, Trikamji B, Khanli HM, Scheuner MT, Jamal NI, Hanssen AM. A case of Fragile X-associated tremor/ataxia syndrome (FXTAS). J Clin Neurosci 2019; 66:269-270. [DOI: 10.1016/j.jocn.2019.05.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 05/27/2019] [Indexed: 11/26/2022]
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Ligsay A, El-Deeb M, Salcedo-Arellano MJ, Schloemerkemper N, Grayson JS, Hagerman R. General Anesthetic Use in Fragile X Spectrum Disorders. J Neurosurg Anesthesiol 2019; 31:285-290. [PMID: 29734272 PMCID: PMC6215737 DOI: 10.1097/ana.0000000000000508] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The fragile X premutation is characterized by a repeat expansion mutation (between 55 to 200 CGG repeats) in the fragile X mental retardation 1 (FMR1) gene, which leads to RNA toxicity at the cellular level. This may cause patients with the premutation to be particularly susceptible to environmental toxins, which could manifest clinically as new or worsening ataxia and memory loss. Multiple published case reports have also suggested general anesthetics as a potential toxin leading to negative side effects when used in patients with fragile X-associated disorders. However, at this time, there have been no formal research studies regarding cellular changes or long-term clinical manifestations after general anesthetic use in this population. This review aims to highlight previous case reports regarding sequelae related to general anesthetic use in fragile X-associated disorders. New case reports related to this phenomenon are also included.
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Affiliation(s)
- Andrew Ligsay
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, CA, USA
- University of California, Davis School of Medicine, Sacramento, CA, USA
| | - Marwa El-Deeb
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, CA, USA
- Department of Pediatrics, University of California, Davis Medical Center, Sacramento, CA, USA
| | - Maria J Salcedo-Arellano
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, CA, USA
- Department of Pediatrics, University of California, Davis Medical Center, Sacramento, CA, USA
| | - Nina Schloemerkemper
- Department of Anesthesiology and Pain Medicine, University of California, Davis Medical Center, Sacramento, CA, USA
| | - Jeremy S. Grayson
- Department of Anesthesia, Rutgers University Robert Wood Johnson Medical School, New Brunswick, NJ, USA
| | - Randi Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California, Davis Medical Center, Sacramento, CA, USA
- Department of Pediatrics, University of California, Davis Medical Center, Sacramento, CA, USA
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Hall DA, Stebbins GT, Jacquemont S, Berry-Kravis E, Goetz CG, Hagerman R, Zhang L, Leehey MA. Clinimetric Properties of the Fragile X-associated Tremor Ataxia Syndrome Rating Scale. Mov Disord Clin Pract 2019; 6:120-124. [PMID: 30838310 DOI: 10.1002/mdc3.12708] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 08/27/2018] [Accepted: 09/15/2018] [Indexed: 11/07/2022] Open
Abstract
Background There are currently no proven treatments for fragile X-associated tremor and ataxia syndrome (FXTAS). Validated outcome measures are needed in order to plan and conduct clinical trials to aid in the development of therapy. Methods This study examined the reliability and construct validity of the FXTAS Rating Scale. The study was conducted by using ratings from movement disorder specialists, who were blinded to gene status, on the FXTAS Rating Scale. Results In 295 premutation carriers with and without FXTAS, 33 scale items showed a high level of overall reliability, adequate item-to-total correlations and construct validity. Factor analysis revealed four components. Conclusions The result demonstrates that many items in the scale meet standard clinimetric criteria, but modification of the scale improved the overall utility.
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Affiliation(s)
- Deborah A Hall
- Department of Neurological Sciences and Pediatrics Rush University Chicago Illinois United States
| | - Glenn T Stebbins
- Department of Neurological Sciences and Pediatrics Rush University Chicago Illinois United States
| | | | - Elizabeth Berry-Kravis
- Department of Neurological Sciences and Pediatrics Rush University Chicago Illinois United States
- Department of Pediatrics Rush University Chicago Illinois United States
| | - Christopher G Goetz
- Department of Neurological Sciences and Pediatrics Rush University Chicago Illinois United States
| | - Randi Hagerman
- MIND Institute and Department of Pediatrics University of California Davis School of Medicine Sacramento CA United States
| | - Lin Zhang
- Department of Neurology University of California Davis School of Medicine Sacramento CA United States
| | - Maureen A Leehey
- Department of Neurology University of Colorado School of Medicine Aurora Colorado United States
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Fragile X syndrome and fragile X-associated tremor ataxia syndrome. HANDBOOK OF CLINICAL NEUROLOGY 2018; 147:377-391. [PMID: 29325626 DOI: 10.1016/b978-0-444-63233-3.00025-7] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Fragile X-associated disorders encompass several conditions, which are caused by expansion mutations in the fragile X mental retardation 1 (FMR1) gene. Fragile X syndrome is the most common inherited etiology of intellectual disability and results from a full mutation or >200 CGG repeats in FMR1. It is associated with developmental delay, autism spectrum disorder, and seizures. Fragile X-associated tremor/ataxia syndrome is a progressive neurodegenerative disease that occurs in premutation carriers of 55-200 CGG repeats in FMR1 and is characterized by kinetic tremor, gait ataxia, parkinsonism, executive dysfunction, and neuropathy. Fragile X-associated primary ovarian insufficiency also occurs in premutation carrier women and manifests with infertility and early menopause. The diseases constituting fragile X-associated disorders differ mechanistically, due to the distinct molecular properties of premutation versus full mutations. Fragile X syndrome occurs when there is a lack of fragile X mental retardation protein (FMRP) due to FMR1 methylation and silencing. In fragile X-associated tremor ataxia syndrome, a toxic gain of function is postulated with the production of excess CGG repeat-containing FMR1 mRNA, abnormal translation of the repeat sequence leading to production of polyglycine, polyalanine, and other polypeptides and to outright deficits in translation leading to reduced FMRP at larger premutation sizes. The changes in underlying brain chemistry due to FMR1 mutations have led to therapeutic studies in these disorders, with some progress being made in fragile X syndrome. This paper also summarizes indications for testing, genetic counseling issues, and what the future holds for these disorders.
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Derbis M, Konieczny P, Walczak A, Sekrecki M, Sobczak K. Quantitative Evaluation of Toxic Polyglycine Biosynthesis and Aggregation in Cell Models Expressing Expanded CGG Repeats. Front Genet 2018; 9:216. [PMID: 29971092 PMCID: PMC6018535 DOI: 10.3389/fgene.2018.00216] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2018] [Accepted: 05/28/2018] [Indexed: 12/23/2022] Open
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder caused by expanded CGG (CGGexp) trinucleotides in the 5′UTR of the FMR1 gene encoding fragile X mental retardation protein (FMRP). The patients, with the number of the repeats ranging from 55 to 200, show specific manifestation of clinical symptoms that include intention tremor, gait ataxia, cognitive deficits, and brain atrophy. Accumulation of toxic polyglycine (FMRpolyG), a by-product of the CGGexp repeat-associated non-ATG (RAN) translation, is considered to be one of the main factors triggering neurodegenerative processes in FXTAS patients. Nevertheless, the nature of the FMRpolyG-induced cell damage, especially in the context of its soluble and inclusion-associated forms, is still elusive. Targeting either biosynthesis, cellular stability or aggregation capacity of toxic FMRpolyG could be considered as a potential therapeutic strategy for FXTAS. Therefore, we tested a variety of quantitative methods based on forced expression of genetic constructs carrying CGGexp repeats in the context of the FMR1 5′UTR fused to GFP, mCherry or Firefly luciferase gene in or out of frame to the polyglycine encoding sequence. We show that FMRpolyG translation either from native or an AUG-induced start codon as well as the translation yield of the FMRP open reading frame equivalent located downstream of the CGGexp element can be effectively estimated using fluorescence microscopy, flow cytometry or luciferase assay. We also quantitatively estimated soluble fraction and insoluble form of FMRpolyG aggregated in foci using an electrophoretic separation of cell lysates and fluorescence microscopy, respectively. Importantly, we show that dependent on a fusion tag, FMRpolyG has a different potential for aggregate formation. Our established protocols enable sensitive tracking of FMRP and FMRpolyG quantitative and qualitative changes after treatment with potential therapeutic agents for FXTAS. Furthermore, they can be modified for application to other RAN translation- and aggregation-related diseases.
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Affiliation(s)
- Magdalena Derbis
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, Poland
| | - Patryk Konieczny
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, Poland
| | - Agnieszka Walczak
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, Poland
| | - Michal Sekrecki
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, Poland
| | - Krzysztof Sobczak
- Department of Gene Expression, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznań, Poland
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Abstract
PURPOSE OF REVIEW Tremor, which is a rhythmic oscillation of a body part, is among the most common involuntary movements. Rhythmic oscillations may manifest in a variety of ways; as a result, a rich clinical phenomenology surrounds tremor. For this reason, diagnosing tremor disorders can be particularly challenging. The aim of this article is to provide the reader with a straightforward approach to the diagnosis and management of patients with tremor. RECENT FINDINGS Scientific understanding of the pathophysiologic basis of tremor disorders has grown considerably in recent years with the use of a broad range of neuroimaging approaches and rigorous, controlled postmortem studies. The basal ganglia and cerebellum are structures that seem to play a prominent role. SUMMARY The diagnosis of tremor disorders is challenging. The approach to tremor involves a history and a neurologic examination that is focused on the nuances of tremor phenomenology, of which there are many. The evaluation should begin with a tremor history and a focused neurologic examination. The examination should attend to the many subtleties of tremor phenomenology. Among other things, the history and examination are used to establish whether the main type of tremor is an action tremor (ie, postural, kinetic, or intention tremor) or a resting tremor. The clinician should then formulate two sets of differential diagnoses: disorders in which action tremor is the predominant tremor versus those in which resting tremor is the main tremor. Among the most common of the former type are essential tremor, enhanced physiologic tremor, drug-induced tremor, dystonic tremor, orthostatic tremor, and cerebellar tremor. Parkinson disease is the most common form of resting tremor, along with drug-induced resting tremor. This article details the clinical features of each of these as well as other tremor disorders.
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27
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Autistic Phenotype of Permutation and Intermediate Alleles of FMR1 Gene. IRANIAN JOURNAL OF PEDIATRICS 2017. [DOI: 10.5812/ijp.9445] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Transmission of double FMR1 allelic premutations in a family. Genes Genomics 2017. [DOI: 10.1007/s13258-016-0506-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Wang JY, Hessl D, Hagerman RJ, Simon TJ, Tassone F, Ferrer E, Rivera SM. Abnormal trajectories in cerebellum and brainstem volumes in carriers of the fragile X premutation. Neurobiol Aging 2017; 55:11-19. [PMID: 28391068 DOI: 10.1016/j.neurobiolaging.2017.03.018] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 01/27/2017] [Accepted: 03/10/2017] [Indexed: 10/19/2022]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder typically affecting male premutation carriers with 55-200 CGG trinucleotide repeat expansions in the FMR1 gene after age 50. The aim of this study was to examine whether cerebellar and brainstem changes emerge during development or aging in late life. We retrospectively analyzed magnetic resonance imaging scans from 322 males (age 8-81 years). Volume changes in the cerebellum and brainstem were contrasted with those in the ventricles and whole brain. Compared to the controls, premutation carriers without FXTAS showed significantly accelerated volume decrease in the cerebellum and whole brain, flatter inverted U-shaped trajectory of the brainstem, and larger ventricles. Compared to both older controls and premutation carriers without FXTAS, carriers with FXTAS exhibited significant volume decrease in the cerebellum and whole brain and accelerated volume decrease in the brainstem. We therefore conclude that cerebellar and brainstem volumes were likely affected during both development and progression of neurodegeneration in premutation carriers, suggesting that interventions may need to start early in adulthood to be most effective.
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Affiliation(s)
- Jun Yi Wang
- Center for Mind and Brain, University of California-Davis, Davis, CA, USA.
| | - David Hessl
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California-Davis Medical Center, Sacramento, CA, USA; Department of Psychiatry and Behavioral Sciences, University of California-Davis, School of Medicine, Sacramento, CA, USA
| | - Randi J Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California-Davis Medical Center, Sacramento, CA, USA; Department of Pediatrics, University of California-Davis, School of Medicine, Sacramento, CA, USA
| | - Tony J Simon
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California-Davis Medical Center, Sacramento, CA, USA; Department of Psychiatry and Behavioral Sciences, University of California-Davis, School of Medicine, Sacramento, CA, USA
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California-Davis Medical Center, Sacramento, CA, USA; Department of Biochemistry and Molecular Medicine, University of California-Davis, School of Medicine, Sacramento, CA, USA
| | - Emilio Ferrer
- Department of Psychology, University of California-Davis, Davis, CA, USA
| | - Susan M Rivera
- Center for Mind and Brain, University of California-Davis, Davis, CA, USA; Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California-Davis Medical Center, Sacramento, CA, USA; Department of Psychology, University of California-Davis, Davis, CA, USA
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Leitlinien zur molekulargenetischen Diagnostik: Fragiles-X Syndrom und andere FMR1-assoziierte Syndrome. MED GENET-BERLIN 2017. [DOI: 10.1007/s11825-016-0113-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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31
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Seritan AL, Kim K, Benjamin I, Seritan I, Hagerman RJ. Risk Factors for Cognitive Impairment in Fragile X-Associated Tremor/Ataxia Syndrome. J Geriatr Psychiatry Neurol 2016; 29:328-337. [PMID: 27647792 PMCID: PMC5357600 DOI: 10.1177/0891988716666379] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disease with motor, psychiatric, and cognitive manifestations that occurs in carriers of the fragile X mental retardation 1 ( FMR1) gene premutations. This was a retrospective chart review of 196 individuals (127 men and 69 women) with FXTAS. Forty-six (23%) participants were cognitively impaired, of whom 19 (10%) had dementia. Risk factors for dementia were examined (CGG repeat size; alcohol, benzodiazepine, and opioid use; diabetes; hyperlipidemia; hypertension; hypothyroidism; obesity; sleep apnea; surgeries with general anesthesia; depression; family history of dementia). Thirteen individuals with FXTAS and dementia were then compared to 13 cognitively intact individuals matched on age, gender, and FXTAS stage. CGG repeat size was significantly higher (mean = 98.5, standard deviation [SD] = 22.2) in the dementia group, compared to the cognitively intact group (mean = 81.6, SD = 11.5; P = .0256). These results show that CGG repeat size is a risk factor for FXTAS dementia.
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Affiliation(s)
- Andreea L. Seritan
- Department of Psychiatry, University of California, San Francisco, San Francisco, California
| | - Kyoungmi Kim
- Department of Public Health Sciences, Division of Biostatistics, University of California, Davis, Davis California,Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, Sacramento, California
| | | | - Ioana Seritan
- University of California, Berkeley, Berkeley, California
| | - Randi J. Hagerman
- Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, Sacramento, California,Department of Pediatrics, University of California, Davis Medical Center, Sacramento, California
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Entezari A, Khaniani MS, Bahrami T, Derakhshan SM, Darvish H. Screening for intermediate CGG alleles of FMR1 gene in male Iranian patients with Parkinsonism. Neurol Sci 2016; 38:123-128. [DOI: 10.1007/s10072-016-2723-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 09/01/2016] [Indexed: 02/01/2023]
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Robertson EE, Hall DA, McAsey AR, O'Keefe JA. Fragile X-associated tremor/ataxia syndrome: phenotypic comparisons with other movement disorders. Clin Neuropsychol 2016; 30:849-900. [PMID: 27414076 PMCID: PMC7336900 DOI: 10.1080/13854046.2016.1202239] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 06/12/2016] [Indexed: 12/16/2022]
Abstract
OBJECTIVE The purpose of this paper is to review the typical cognitive and motor impairments seen in fragile X-associated tremor/ataxia syndrome (FXTAS), essential tremor (ET), Parkinson disease (PD), spinocerebellar ataxias (SCAs), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP) in order to enhance diagnosis of FXTAS patients. METHODS We compared the cognitive and motor phenotypes of FXTAS with each of these other movement disorders. Relevant neuropathological and neuroimaging findings are also reviewed. Finally, we describe the differences in age of onset, disease severity, progression rates, and average lifespan in FXTAS compared to ET, PD, SCAs, MSA, and PSP. We conclude with a flow chart algorithm to guide the clinician in the differential diagnosis of FXTAS. RESULTS By comparing the cognitive and motor phenotypes of FXTAS with the phenotypes of ET, PD, SCAs, MSA, and PSP we have clarified potential symptom overlap while elucidating factors that make these disorders unique from one another. In summary, the clinician should consider a FXTAS diagnosis and testing for the Fragile X mental retardation 1 (FMR1) gene premutation if a patient over the age of 50 (1) presents with cerebellar ataxia and/or intention tremor with mild parkinsonism, (2) has the middle cerebellar peduncle (MCP) sign, global cerebellar and cerebral atrophy, and/or subcortical white matter lesions on MRI, or (3) has a family history of fragile X related disorders, intellectual disability, autism, premature ovarian failure and has neurological signs consistent with FXTAS. Peripheral neuropathy, executive function deficits, anxiety, or depression are supportive of the diagnosis. CONCLUSIONS Distinct profiles in the cognitive and motor domains between these movement disorders may guide practitioners in the differential diagnosis process and ultimately lead to better medical management of FXTAS patients.
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Affiliation(s)
- Erin E Robertson
- a Department of Anatomy and Cell Biology , Rush University , Chicago , IL , USA
| | - Deborah A Hall
- b Department of Neurological Sciences , Rush University , Chicago , IL , USA
| | - Andrew R McAsey
- a Department of Anatomy and Cell Biology , Rush University , Chicago , IL , USA
| | - Joan A O'Keefe
- a Department of Anatomy and Cell Biology , Rush University , Chicago , IL , USA
- b Department of Neurological Sciences , Rush University , Chicago , IL , USA
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Abstract
Many physicians are unaware of the many phenotypes associated with the fragile X premutation, an expansion in the 5' untranslated region of the fragile X mental retardation 1 (FMR1) gene that consists of 55-200 CGG repeats. The most severe of these phenotypes is fragile X-associated tremor/ataxia syndrome (FXTAS), which occurs in the majority of ageing male premutation carriers but in fewer than 20% of ageing women with the premutation. The prevalence of the premutation is 1 in 150-300 females, and 1 in 400-850 males, so physicians are likely to see people affected by FXTAS. Fragile X DNA testing is broadly available in the Western world. The clinical phenotype of FXTAS at presentation can vary and includes intention tremor, cerebellar ataxia, neuropathic pain, memory and/or executive function deficits, parkinsonian features, and psychological disorders, such as depression, anxiety and/or apathy. FXTAS causes brain atrophy and white matter disease, usually in the middle cerebellar peduncles, the periventricular area, and the splenium and/or genu of the corpus callosum. Here, we review the complexities involved in the clinical management of FXTAS and consider how targeted treatment for these clinical features of FXTAS will result from advances in our understanding of the molecular mechanisms that underlie this neurodegenerative disorder. Such targeted approaches should also be more broadly applicable to earlier forms of clinical involvement among premutation carriers.
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Tamás G, Kovács N, Varga NÁ, Barsi P, Erőss L, Molnár MJ, Balás I. Deep brain stimulation or thalamotomy in fragile X-associated tremor/ataxia syndrome? Case report. Neurol Neurochir Pol 2016; 50:303-8. [PMID: 27375149 DOI: 10.1016/j.pjnns.2016.04.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Revised: 03/17/2016] [Accepted: 04/13/2016] [Indexed: 10/21/2022]
Abstract
We present the case of a 66-year-old man who has been treated for essential tremor since the age of 58. He developed mild cerebellar gait ataxia seven years after tremor onset. Moderate, global brain atrophy was identified on MRI scans. At the age of 68, only temporary tremor relief could be achieved by bilateral deep brain stimulation of the ventral intermedius nucleus of the thalamus. Bilateral stimulation of the subthalamic nucleus also resulted only in transient improvement. In the meantime, progressive gait ataxia and tetraataxia developed accompanied by other cerebellar symptoms, such as nystagmus and scanning speech. These correlated with progressive development of bilateral symmetric hyperintensity of the middle cerebellar peduncles on T2 weighted MRI scans. Genetic testing revealed premutation of the FMR1 gene, establishing the diagnosis of fragile X-associated tremor/ataxia syndrome. Although this is a rare disorder, it should be taken into consideration during preoperative evaluation of essential tremor. Postural tremor ceased two years later after thalamotomy on the left side, while kinetic tremor of the right hand also improved.
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Affiliation(s)
- Gertrúd Tamás
- Department of Neurology, Semmelweis University, Budapest, Hungary.
| | - Norbert Kovács
- Department of Neurology, University of Pécs, Pécs, Hungary
| | - Noémi Ágnes Varga
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - Péter Barsi
- MR Research Centre, Semmelweis University, Budapest, Hungary
| | - Loránd Erőss
- National Institute of Clinical Neurosciences, Budapest, Hungary
| | - Mária Judit Molnár
- Institute of Genomic Medicine and Rare Disorders, Semmelweis University, Budapest, Hungary
| | - István Balás
- Department of Neurosurgery, University of Pécs, Pécs, Hungary
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Martínez-Cerdeño V, Lechpammer M, Lott A, Schneider A, Hagerman R. Fragile X-Associated Tremor/Ataxia Syndrome in a Man in His 30s. JAMA Neurol 2015; 72:1070-3. [PMID: 26368352 DOI: 10.1001/jamaneurol.2015.1138] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Verónica Martínez-Cerdeño
- Department of Pathology and Laboratory Medicine, University of California-Davis2Institute for Pediatric Regenerative Medicine, Shriners Hospitals for Children-Northern California, Sacramento3MIND Institute, University of California-Davis Medical Center
| | - Mirna Lechpammer
- Department of Pathology and Laboratory Medicine, University of California-Davis
| | - Aisha Lott
- MIND Institute, University of California-Davis Medical Center
| | - Andrea Schneider
- MIND Institute, University of California-Davis Medical Center4Department of Pediatrics, University of California-Davis Medical Center
| | - Randi Hagerman
- MIND Institute, University of California-Davis Medical Center4Department of Pediatrics, University of California-Davis Medical Center
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De Pablo-Fernandez E, Doherty KM, Holton JL, Revesz T, Djamshidian A, Limousin P, Bhatia KP, Warner TT, Lees AJ, Ling H. Concomitant fragile X-associated tremor ataxia syndrome and Parkinson's disease: a clinicopathological report of two cases. J Neurol Neurosurg Psychiatry 2015; 86:934-6. [PMID: 25476004 PMCID: PMC4516009 DOI: 10.1136/jnnp-2014-309460] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 11/13/2014] [Indexed: 11/25/2022]
Affiliation(s)
- Eduardo De Pablo-Fernandez
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, UK Queen Square Brain Bank for Neurological Disorders, UCL Institute of Neurology, London, UK
| | - Karen M Doherty
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, UK Queen Square Brain Bank for Neurological Disorders, UCL Institute of Neurology, London, UK
| | - Janice L Holton
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, UK Queen Square Brain Bank for Neurological Disorders, UCL Institute of Neurology, London, UK National Hospital for Neurology and Neurosurgery, Queen Square, UCL Hospitals NHS Foundation Trust, London, UK
| | - Tamas Revesz
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, UK Queen Square Brain Bank for Neurological Disorders, UCL Institute of Neurology, London, UK
| | - Atbin Djamshidian
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, UK
| | - Patricia Limousin
- National Hospital for Neurology and Neurosurgery, Queen Square, UCL Hospitals NHS Foundation Trust, London, UK Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK
| | - Kailash P Bhatia
- National Hospital for Neurology and Neurosurgery, Queen Square, UCL Hospitals NHS Foundation Trust, London, UK Sobell Department of Motor Neuroscience, UCL Institute of Neurology, London, UK
| | - Thomas T Warner
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, UK Queen Square Brain Bank for Neurological Disorders, UCL Institute of Neurology, London, UK National Hospital for Neurology and Neurosurgery, Queen Square, UCL Hospitals NHS Foundation Trust, London, UK
| | - Andrew J Lees
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, UK Queen Square Brain Bank for Neurological Disorders, UCL Institute of Neurology, London, UK
| | - Helen Ling
- Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, London, UK Queen Square Brain Bank for Neurological Disorders, UCL Institute of Neurology, London, UK
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Muzar Z, Lozano R, Schneider A, Adams PE, Faradz SMH, Tassone F, Hagerman RJ. Methadone use in a male with the FMRI premutation and FXTAS. Am J Med Genet A 2015; 167:1354-9. [PMID: 25900641 DOI: 10.1002/ajmg.a.37030] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2013] [Accepted: 02/08/2015] [Indexed: 01/18/2023]
Abstract
The fragile X-associated tremor ataxia syndrome (FXTAS) is caused by the premutation in FMR1 gene. Recent reports of environmental toxins appear to worsen the progression of FXTAS. Here we present a case of male adult with FXTAS and a long history of methadone use. The patient shows a faster progression in both symptoms of disease and MRI changes compared to what is typically seen in FXTAS. There has been no research regarding the role of narcotics in onset, progression, and severity of FXTAS symptoms. However, research has shown that narcotics can have a negative impact on several neurodegenerative diseases, and we hypothesize that in this particular case, methadone may have contributed to a faster progression of FXTAS as well as exacerbating white matter disease through RNA toxicity seen in premutation carriers.
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Affiliation(s)
- Zukhrofi Muzar
- Center for Biomedical Research, Faculty of Medicine Diponegoro University Semarang, Central Java, Indonesia.,Medical Investigation of Neurodevelopmental Disorders MIND Institute, University of California Davis Medical Center, Sacramento, California
| | - Reymundo Lozano
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, UC Davis Medical Center, Sacramento, California
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, UC Davis Medical Center, Sacramento, California
| | - Patrick E Adams
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, UC Davis Medical Center, Sacramento, California
| | - Sultana M H Faradz
- Center for Biomedical Research, Faculty of Medicine Diponegoro University Semarang, Central Java, Indonesia
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, University of California Davis Medical Center, Sacramento, California.,Department of Biochemistry and Molecular Medicine, School of Medicine, University of California at Davis, Davis, Califonia
| | - Randi J Hagerman
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, University of California Davis Medical Center, Sacramento, California.,Department of Pediatrics, UC Davis Medical Center, Sacramento, California
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Hagerman PJ, Hagerman RJ. Fragile X-associated tremor/ataxia syndrome. Ann N Y Acad Sci 2015; 1338:58-70. [PMID: 25622649 PMCID: PMC4363162 DOI: 10.1111/nyas.12693] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 12/04/2014] [Accepted: 12/18/2014] [Indexed: 12/20/2022]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder that affects some but not all carriers of small, noncoding CGG-repeat expansions (55-200 repeats; premutation) within the fragile X gene (FMR1). Principal features of FXTAS include intention tremor, cerebellar ataxia, Parkinsonism, memory and executive function deficits, autonomic dysfunction, brain atrophy with white matter disease, and cognitive decline. Although FXTAS was originally considered to be confined to the premutation range, rare individuals with a gray zone (45-54 repeats) or an unmethylated full mutation (>200 repeats) allele have now been described, the constant feature of the disorder remaining the requirement for FMR1 expression, in contradistinction to the gene silencing mechanism of fragile X syndrome. Although transcriptional activity is required for FXTAS pathogenesis, the specific trigger(s) for FXTAS pathogenesis remains elusive, highlighting the need for more research in this area. This need is underscored by recent neuroimaging findings of changes in the central nervous system that consistently appear well before the onset of clinical symptoms, thus creating an opportunity to delay or prevent the appearance of FXTAS.
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Affiliation(s)
- Paul J Hagerman
- Department of Biochemistry and Molecular Medicine, University of California , Davis , School of Medicine, Davis, California; The MIND Institute, University of California , Davis , Health System, Sacramento, California
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40
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Berman RF, Schwartzer JJ, Hunsaker MR. Mouse Models of the Fragile X Tremor/Ataxia Syndrome (FXTAS) and the Fragile X Premutation. Mov Disord 2015. [DOI: 10.1016/b978-0-12-405195-9.00039-1] [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] Open
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Muzar Z, Adams PE, Schneider A, Hagerman RJ, Lozano R. Addictive substances may induce a rapid neurological deterioration in fragile X-associated tremor ataxia syndrome: A report of two cases. Intractable Rare Dis Res 2014; 3:162-5. [PMID: 25606366 PMCID: PMC4298646 DOI: 10.5582/irdr.2014.01023] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 11/28/2014] [Indexed: 12/13/2022] Open
Abstract
A debilitating late-onset disorder of the premutation in the FMR1 gene is the neurodegenerative disorder fragile X-associated tremor ataxia syndrome (FXTAS). We report two patients with FXTAS who have a history of substance abuse (opiates, alcohol, and cocaine) which may have exacerbated their rapid neurological deterioration with FXTAS. There has been no case report regarding the role of substance abuse in onset, progression, and severity of FXTAS symptoms. However, research has shown that substance abuse can have a negative impact on several neurodegenerative diseases, and we propose that in these cases, substance abuse contributed to a faster progression of FXTAS as well as exacerbated white matter disease.
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Affiliation(s)
- Zukhrofi Muzar
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, Sacramento, CA, USA
| | - Patrick E. Adams
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, Sacramento, CA, USA
- Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, Sacramento, CA, USA
- Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
| | - Randi J. Hagerman
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, Sacramento, CA, USA
- Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
- Address correspondence to: Dr. Randi J. Hagerman, MIND Institute, UC Davis Health System, 2825 50th Street, Sacramento, CA 95817, USA. E-mail:
| | - Reymundo Lozano
- Medical Investigation of Neurodevelopmental Disorders MIND Institute, Sacramento, CA, USA
- Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
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42
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Muzar Z, Lozano R. Current research, diagnosis, and treatment of fragile X-associated tremor/ataxia syndrome. Intractable Rare Dis Res 2014; 3:101-9. [PMID: 25606360 PMCID: PMC4298640 DOI: 10.5582/irdr.2014.01029] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 11/30/2014] [Indexed: 12/13/2022] Open
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is caused by a premutation CGG-repeat expansion in the 5'UTR of the fragile X mental retardation 1 (FMR1) gene. The classical clinical manifestations include tremor, cerebellar ataxia, cognitive decline and psychiatric disorders. Other less frequent features are peripheral neuropathy and autonomic dysfunction. Cognitive decline, a form of frontal subcortical dementia, memory loss and executive function deficits are also characteristics of this disorder. In this review, we present an expansion of recommendations for genetic testing for adults with suspected premutation disorders and provide an update of the clinical, radiological and molecular research of FXTAS, as well as the current research in the treatment for this intractable complex neurodegenerative genetic disorder.
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Affiliation(s)
- Zukhrofi Muzar
- UC Davis MIND Institute and Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
| | - Reymundo Lozano
- UC Davis MIND Institute and Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
- Address correspondence to: Dr. Reymundo Lozano, UC Davis MIND Institute and Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA. E-mail:
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Schneider A, Ligsay A, Hagerman RJ. Fragile X syndrome: an aging perspective. ACTA ACUST UNITED AC 2014; 18:68-74. [PMID: 23949830 DOI: 10.1002/ddrr.1129] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 04/24/2012] [Accepted: 06/19/2012] [Indexed: 11/11/2022]
Abstract
Cognitive and behavioral correlates of molecular variations related to the FMR1 gene have been studied rather extensively, but research about the long-term outcome in individuals with fragile X spectrum disorders remains sparse. In this review, we present an overview of aging research and recent findings in regard to cellular and clinical manifestations of aging in fragile X syndrome, and the FMR1 premutation.
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Affiliation(s)
- Andrea Schneider
- MIND Institute, University of California at Davis Medical Center, Sacramento, California, USA.
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Seritan AL, Nguyen DV, Mu Y, Tassone F, Bourgeois JA, Schneider A, Cogswell J, Cook K, Leehey M, Grigsby J, Olichney JM, Adams P, Legg W, Zhang L, Hagerman P, Hagerman RJ. Memantine for fragile X-associated tremor/ataxia syndrome: a randomized, double-blind, placebo-controlled trial. J Clin Psychiatry 2014; 75:264-71. [PMID: 24345444 PMCID: PMC4296896 DOI: 10.4088/jcp.13m08546] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Accepted: 07/12/2013] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Memantine, an uncompetitive N-methyl-d-aspartate receptor antagonist, is currently approved by the US Food and Drug Administration for the treatment of moderate to severe Alzheimer's disease. Anecdotal reports have suggested that memantine may improve neurologic and cognitive symptoms of individuals with the neurodegenerative disease fragile X-associated tremor/ataxia syndrome (FXTAS); however, its efficacy and safety in this population have not been assessed in a controlled trial. METHOD Individuals with FXTAS aged 34-80 years were enrolled in a randomized, double-blind, placebo-controlled, 1-year trial between September 2007 and August 2012. Inclusion required definite, probable, or possible FXTAS in clinical stages 1-5 according to previously published criteria. Primary outcome measures were the Behavioral Dyscontrol Scale (BDS) score and CATSYS intention tremor severity. RESULTS Ninety-four participants were randomized from 205 screened; of those, 43 and 45 started treatment with memantine (titrated to 10 mg twice daily) and placebo, respectively. Thirty-four participants receiving memantine and 36 receiving placebo completed the 1-year endpoint assessment (n = 70). Intention-to-treat analysis showed no improvement with respect to intention tremor severity (mean [SD] values with memantine vs placebo: 1.05 [0.73] vs 1.89 [2.19], P = .047) or BDS score (16.12 [5.43] vs 15.72 [3.93], P = .727) at follow-up. Post hoc analyses of participants with early FXTAS (stage ≤ 3), those with late FXTAS (stage > 3), and those in different age groups (≤ 65 years and > 65 years) also indicated no significant improvement. More frequent mild adverse events were observed in the placebo group, while more frequent moderate adverse events occurred in the memantine group (P = .007). CONCLUSION This randomized, double-blind, placebo-controlled trial of memantine for individuals with FXTAS showed no benefit compared to placebo with respect to the selected outcome measures. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT00584948.
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Affiliation(s)
- Andreea L. Seritan
- Department of Psychiatry and Behavioral Sciences, University of California Davis Medical Center, Sacramento, CA,Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA
| | - Danh V. Nguyen
- Department of Medicine, University of California Irvine, Irvine, CA,Institute for Clinical and Translational Science, University of California Irvine, Irvine, CA
| | - Yi Mu
- Department of Public Health Sciences, University of California Davis, Davis CA
| | - Flora Tassone
- Department of Biochemistry and Molecular Medicine, University of California Davis, Davis, CA
| | - James A. Bourgeois
- Department of Psychiatry, University of California San Francisco, San Francisco, CA
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA,Department of Pediatrics, University of California Davis Medical Center, Sacramento, CA
| | - Jennifer Cogswell
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA
| | - Kylee Cook
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA
| | - Maureen Leehey
- Department of Neurology, University of Colorado School of Medicine, Denver, Colorado
| | - Jim Grigsby
- Departments of Psychology and Medicine, University of Colorado Denver, Denver, Colorado
| | - John M. Olichney
- Department of Neurology, University of California Davis, Sacramento, CA,Center for Mind and Brain, University of California Davis, Davis, CA
| | - Patrick Adams
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA
| | - Wendi Legg
- Department of Neurology, University of Colorado School of Medicine, Denver, Colorado
| | - Lin Zhang
- Department of Neurology, University of California Davis, Sacramento, CA
| | - Paul Hagerman
- Department of Biochemistry and Molecular Medicine, University of California Davis, Davis, CA
| | - Randi J. Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA,Department of Pediatrics, University of California Davis Medical Center, Sacramento, CA
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Polussa J, Schneider A, Hagerman R. Molecular Advances Leading to Treatment Implications for Fragile X Premutation Carriers. BRAIN DISORDERS & THERAPY 2014; 3:1000119. [PMID: 25436181 PMCID: PMC4245015 DOI: 10.4172/2168-975x.1000119] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fragile X syndrome (FXS) is the most common single gene cause of intellectual disability and it is characterized by a CGG expansion of more than 200 repeats in the FMR1 gene, leading to methylation of the promoter and gene silencing. The fragile X premutation, characterized by a 55 to 200 CGG repeat expansion, causes health problems and developmental difficulties in some, but not all, carriers. The premutation causes primary ovarian insufficiency in approximately 20% of females, psychiatric problems (including depression and/or anxiety) in approximately 50% of carriers and a neurodegenerative disorder, the fragile X-associated tremor ataxia syndrome (FXTAS), in approximately 40% of males and 16% of females later in life. Recent clinical studies in premutation carriers have expanded the health problems that may be seen. Advances in the molecular pathogenesis of the premutation have shown significant mitochondrial dysfunction and oxidative stress in neurons which may be amenable to treatment. Here we review the clinical problems of carriers and treatment recommendations.
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Affiliation(s)
- Jonathan Polussa
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health System, Sacramento, California, USA
- Department of Pediatrics, University of California Davis Health System, Sacramento, California, USA
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health System, Sacramento, California, USA
- Department of Pediatrics, University of California Davis Health System, Sacramento, California, USA
| | - Randi Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Health System, Sacramento, California, USA
- Department of Pediatrics, University of California Davis Health System, Sacramento, California, USA
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Trost N, Cook M, Hammersley E, Bui MQ, Brotchie P, Burgess T, Slater H, Storey E, Loesch DZ. White matter changes in patients with Parkinson's disease carrying small CGG expansion FMR1 alleles: a pilot study. NEURODEGENER DIS 2013; 14:67-76. [PMID: 24401315 DOI: 10.1159/000356190] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Accepted: 10/05/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND/AIMS Alleles of the FMR1 gene containing small expansions of the CGG-trinucleotide repeat comprise premutation and grey-zone alleles. Premutation alleles may cause late-onset Fragile X-associated tremor/ataxia syndrome attributed to the neurotoxic effect of elevated FMR1 transcripts. Our earlier data suggested that both grey-zone and low-end premutation alleles might also play a significant role in the acquisition of the parkinsonian phenotype due to mitochondrial dysfunction caused by elevated FMR1 mRNA toxicity. These data were obtained through clinical and molecular comparisons between carriers of grey-zone/low-end premutation alleles and group-matched non-carrier controls from patients with idiopathic Parkinson's disease (iPD). We aimed to explore the relationship between grey-zone alleles, parkinsonism and white matter changes. METHODS This study compared the extent and severity of white matter hyperintensity (WMH) on magnetic resonance imaging, using a semi-quantitative method, between 11 grey-zone/low-end premutation carriers and 20 non-carrier controls with iPD from our earlier study. Relationships between WMH scores, and cognitive and motor test scores were assessed for carriers and non-carriers. RESULTS Supratentorial WMH scores, and tremor and ataxia motor scores were significantly higher in carriers compared with disease controls. Moreover, some associations between cognitive decline and WMH scores were specific for each respective carrier status category. CONCLUSIONS The results support our earlier claim that grey-zone alleles contribute to the severity of parkinsonism and white matter changes.
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Affiliation(s)
- Nicholas Trost
- MRI Centre, St. Vincent's Hospital Melbourne, Fitzroy, Vic., Australia
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47
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Santa María L, Pugin A, Alliende MA, Aliaga S, Curotto B, Aravena T, Tang HT, Mendoza-Morales G, Hagerman R, Tassone F. FXTAS in an unmethylated mosaic male with fragile X syndrome from Chile. Clin Genet 2013; 86:378-82. [PMID: 24028275 DOI: 10.1111/cge.12278] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 09/04/2013] [Accepted: 09/10/2013] [Indexed: 01/31/2023]
Abstract
Carriers of an FMR1 premutation allele (55-200 CGG repeats) often develop the neurodegenerative disorders, fragile X-associated tremor/ataxia syndrome (FXTAS). Neurological signs of FXTAS, parkinsonism and rapid onset of cognitive decline have not been reported in individuals with an unmethylated full mutation (FM). Here, we report a Chilean family affected with FXS, inherited from a parent carrier of an FMR1 unmethylated full mosaic allele, who presented with a fast progressing FXTAS. This case suggests that the definition of FXTAS may need to be broadened to not only include those with a premutation but also those with an expanded allele in FM range with a lack of methylation leading to elevated FMR1-mRNA expression levels and subsequent RNA toxicity.
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Affiliation(s)
- L Santa María
- Center for Diagnosis and Treatment of Fragile X Syndrome (CDTSXF), INTA University of Chile, Santiago, Chile
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48
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Hagerman R, Hagerman P. Advances in clinical and molecular understanding of the FMR1 premutation and fragile X-associated tremor/ataxia syndrome. Lancet Neurol 2013; 12:786-98. [PMID: 23867198 DOI: 10.1016/s1474-4422(13)70125-x] [Citation(s) in RCA: 238] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Fragile X syndrome, the most common heritable form of cognitive impairment, is caused by epigenetic silencing of the fragile X (FMR1) gene owing to large expansions (>200 repeats) of a non-coding CGG-repeat element. Smaller, so-called premutation expansions (55-200 repeats) can cause a family of neurodevelopmental phenotypes (attention deficit hyperactivity disorder, autism spectrum disorder, seizure disorder) and neurodegenerative (fragile X-associated tremor/ataxia syndrome [FXTAS]) phenotypes through an entirely distinct molecular mechanism involving increased FMR1 mRNA production and toxicity. Results of basic cellular, animal, and human studies have helped to elucidate the underlying RNA toxicity mechanism, while clinical research is providing a more nuanced picture of the range of clinical manifestations. Advances of knowledge on both mechanistic and clinical fronts are driving new approaches to targeted treatment, but two important necessities are emerging: to define the extent to which the mechanisms contributing to FXTAS also contribute to other neurodegenerative and medical disorders, and to redefine FXTAS in view of its differing presentations and associated features.
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Affiliation(s)
- Randi Hagerman
- Department of Pediatrics and the MIND Institute, University of California, Davis, School of Medicine, Davis, CA, USA
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Louis ED, Bain PG, Hallett M, Jankovic J, Vonsattel JPG. What is It? Difficult to Pigeon Hole Tremor: a Clinical-Pathological Study of a Man with Jaw Tremor. TREMOR AND OTHER HYPERKINETIC MOVEMENTS (NEW YORK, N.Y.) 2013; 3. [PMID: 23864988 PMCID: PMC3712322 DOI: 10.7916/d8rn36j6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2013] [Accepted: 05/17/2013] [Indexed: 12/01/2022]
Abstract
Background The phenomenology of tremor is broad and its classification is complicated. Furthermore, the full range of tremor phenomenology with respect to specific neurological and neurodegenerative diseases has not been fully elaborated. Case Report This right-handed man had a chief complaint of jaw tremor, which began approximately 20 years prior to death at age 101 years. He had been diagnosed with essential tremor (ET) by a local doctor. His examination at age 100 years was notable for marked jaw tremor at rest in the absence of other clear features of parkinsonism, mild kinetic tremor of the hands and, in the last year of life, a score of 22/41 on a cognitive screen. A senior movement disorder neurologist raised doubt about the “ET” diagnosis. The history and videotaped examination were reviewed by three additional senior tremor experts, who raised a number of diagnostic possibilities. A complete postmortem examination was performed by a senior neuropathologist, and was notable for the presence of tufted astrocytes, AT8-labeled glial cytoplasmic inclusions, and globose neuronal tangles. These changes were widespread and definitive. A neuropathological diagnosis of progressive supranuclear palsy was assigned. Discussion This case presents with mixed and difficult to clinically classify tremor phenomenology and other neurological findings. The postmortem diagnosis was not predicted based on the clinical features, and it is possible that it does not account for all of the features. The case raises many interesting issues and provides a window into the complexity of the interpretation, nosology, and classification of tremor phenomenology.
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Affiliation(s)
- Elan D Louis
- Department of Neurology, College of Physicians and Surgeons, Columbia University, New York, New York, United States of America ; Department of Epidemiology, Mailman School of Public Health, Columbia University, New York, New York, United States of America
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50
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Abstract
This article summarizes the clinical findings, genetics, pathophysiology, and treatment of fragile X-associated tremor ataxia syndrome. The disorder occurs from a CGG repeat (55-200) expansion in the fragile X mental retardation 1 gene. It manifests clinically in kinetic tremor, gait ataxia, and executive dysfunction, usually in older men who carry the genetic abnormality. The disorder has distinct radiographic and pathologic findings. Symptomatic treatment is beneficial in some patients. The inheritance is X-linked and family members may be at risk for other fragile X-associated disorders. This information is useful to neurologists, general practitioners, and geneticists.
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