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Elias-Mas A, Wang JY, Rodríguez-Revenga L, Kim K, Tassone F, Hessl D, Rivera SM, Hagerman R. Enlarged perivascular spaces and their association with motor, cognition, MRI markers and cerebrovascular risk factors in male fragile X premutation carriers. J Neurol Sci 2024; 461:123056. [PMID: 38772058 DOI: 10.1016/j.jns.2024.123056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 05/15/2024] [Accepted: 05/16/2024] [Indexed: 05/23/2024]
Abstract
FMR1 premutation carriers (55-200 CGG repeats) are at risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative disorder associated with motor and cognitive impairment. Bilateral hyperintensities of the middle cerebellar peduncles (MCP sign) are the major radiological hallmarks of FXTAS. In the general population, enlarged perivascular spaces (PVS) are biomarkers of small vessel disease and glymphatic dysfunction and are associated with cognitive decline. Our aim was to determine if premutation carriers show higher ratings of PVS than controls and whether enlarged PVS are associated with motor and cognitive impairment, MRI features of neurodegeneration, cerebrovascular risk factors and CGG repeat length. We evaluated 655 MRIs (1-10 visits/participant) from 229 carriers (164 with FXTAS and 65 without FXTAS) and 133 controls. PVS in the basal ganglia (BG-EPVS), centrum semiovale, and midbrain were evaluated with a semiquantitative scale. Mixed-effects models were used for statistical analysis adjusting for age. In carriers with FXTAS, we revealed that (1) BG-PVS ratings were higher than those of controls and carriers without FXTAS; (2) BG-PVS severity was associated with brain atrophy, white matter hyperintensities, enlarged ventricles, FXTAS stage and abnormal gait; (3) age-related increase in BG-PVS was associated with cognitive dysfunction; and (4) PVS ratings of all three regions showed robust associations with CGG repeat length and were higher in carriers with the MCP sign than carriers without the sign. This study demonstrates clinical relevance of PVS in FXTAS especially in the basal ganglia region and suggests microangiopathy and dysfunctional cerebrospinal fluid circulation in FXTAS physiopathology.
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Affiliation(s)
- Andrea Elias-Mas
- Radiology Department, Hospital Universitari Mútua de Terrassa, Terrassa, Barcelona, Spain; Institute for Research and Innovation Parc Taulí (I3PT), Sabadell, Spain; Genetics Doctorate Program, Universitat de Barcelona (UB), Barcelona, Spain.
| | - Jun Yi Wang
- Center for Mind and Brain, University of California Davis, CA, United States.
| | - Laia Rodríguez-Revenga
- Biochemistry and Molecular Genetics Department, Hospital Clinic of Barcelona, Barcelona, Spain; CIBER of Rare Diseases (CIBERER), Instituto de Salud Carlos III, Barcelona, Spain; Fundació de Recerca Clínic Barcelona-Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
| | - Kyoungmi Kim
- Department of Public Health Sciences, University of California Davis School of Medicine, Sacramento, CA, United States.
| | - Flora Tassone
- MIND Institute, University of California Davis, Sacramento, CA, United States; Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Sacramento, CA, United States.
| | - David Hessl
- MIND Institute, University of California Davis, Sacramento, CA, United States; Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, United States.
| | - Susan M Rivera
- Center for Mind and Brain, University of California Davis, CA, United States; MIND Institute, University of California Davis, Sacramento, CA, United States; Department of Psychology, University of Maryland, College Park, MD, United States.
| | - Randi Hagerman
- MIND Institute, University of California Davis, Sacramento, CA, United States; Department of Pediatrics, University of California Davis Medical Center, Sacramento, CA, United States.
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2
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Dufour BD, Bartley T, McBride E, Allen E, McLennan YA, Hagerman RJ, Martínez-Cerdeño V. FXTAS Neuropathology Includes Widespread Reactive Astrogliosis and White Matter Specific Astrocyte Degeneration. Ann Neurol 2024; 95:558-575. [PMID: 38069470 PMCID: PMC10922917 DOI: 10.1002/ana.26851] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 01/17/2024]
Abstract
OBJECTIVE Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset progressive genetic neurodegenerative disorder that occurs in FMR1 premutation carriers. The temporal, spatial, and cell-type specific patterns of neurodegeneration in the FXTAS brain remain incompletely characterized. Intranuclear inclusion bodies are the neuropathological hallmark of FXTAS, which are largest and occur most frequently in astrocytes, glial cells that maintain brain homeostasis. Here, we characterized neuropathological alterations in astrocytes in multiple regions of the FXTAS brain. METHODS Striatal and cerebellar sections from FXTAS cases (n = 12) and controls (n = 12) were stained for the astrocyte markers glial fibrillary acidic protein (GFAP) and aldehyde dehydrogenase 1L1 (ALDH1L1) using immunohistochemistry. Reactive astrogliosis severity, the prevalence of GFAP+ fragments, and astrocyte density were scored. Double label immunofluorescence was utilized to detect co-localization of GFAP and cleaved caspase-3. RESULTS FXTAS cases showed widespread reactive gliosis in both grey and white matter. GFAP staining also revealed remarkably severe astrocyte pathology in FXTAS white matter - characterized by a significant and visible reduction in astrocyte density (-38.7% in striatum and - 32.2% in cerebellum) and the widespread presence of GFAP+ fragments reminiscent of apoptotic bodies. White matter specific reductions in astrocyte density were confirmed with ALDH1L1 staining. GFAP+ astrocytes and fragments in white matter were positive for cleaved caspase-3, suggesting that apoptosis-mediated degeneration is responsible for reduced astrocyte counts. INTERPRETATION We have established that FXTAS neuropathology includes robust degeneration of astrocytes, which is specific to white matter. Because astrocytes are essential for maintaining homeostasis within the central nervous system, a loss of astrocytes likely further exacerbates neuropathological progression of other cell types in the FXTAS brain. ANN NEUROL 2024;95:558-575.
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Affiliation(s)
- Brett D. Dufour
- Department of Psychiatry & Behavioral Sciences, UC Davis School of Medicine, Sacramento, CA, USA
- Institute for Pediatric Regenerative Medicine (IPRM), Shriner’s Hospital for Children and UC Davis School of Medicine, Sacramento, CA, USA
- Department of Pathology & Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA
- MIND Institute, UC Davis School of Medicine, Sacramento, CA, USA
| | - Trevor Bartley
- Institute for Pediatric Regenerative Medicine (IPRM), Shriner’s Hospital for Children and UC Davis School of Medicine, Sacramento, CA, USA
- Department of Pathology & Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA
| | - Erin McBride
- Institute for Pediatric Regenerative Medicine (IPRM), Shriner’s Hospital for Children and UC Davis School of Medicine, Sacramento, CA, USA
- Department of Pathology & Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA
| | - Erik Allen
- Institute for Pediatric Regenerative Medicine (IPRM), Shriner’s Hospital for Children and UC Davis School of Medicine, Sacramento, CA, USA
- Department of Pathology & Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA
| | - Yingratana A. McLennan
- Institute for Pediatric Regenerative Medicine (IPRM), Shriner’s Hospital for Children and UC Davis School of Medicine, Sacramento, CA, USA
- Department of Pathology & Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA
| | - Randi J. Hagerman
- MIND Institute, UC Davis School of Medicine, Sacramento, CA, USA
- Department of Pediatrics, UC Davis School of Medicine, Sacramento, CA, USA
| | - Verónica Martínez-Cerdeño
- Institute for Pediatric Regenerative Medicine (IPRM), Shriner’s Hospital for Children and UC Davis School of Medicine, Sacramento, CA, USA
- Department of Pathology & Laboratory Medicine, UC Davis School of Medicine, Sacramento, CA, USA
- MIND Institute, UC Davis School of Medicine, Sacramento, CA, USA
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3
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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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4
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Dijkstra AA, Haify SN, Verwey NA, Prins ND, van der Toorn EC, Rozemuller AJM, Bugiani M, den Dunnen WFA, Todd PK, Charlet-Berguerand N, Willemsen R, Hukema RK, Hoozemans JJM. Neuropathology of FMR1-premutation carriers presenting with dementia and neuropsychiatric symptoms. Brain Commun 2021; 3:fcab007. [PMID: 33709078 PMCID: PMC7936660 DOI: 10.1093/braincomms/fcab007] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 12/15/2020] [Accepted: 12/17/2020] [Indexed: 01/07/2023] Open
Abstract
CGG repeat expansions within the premutation range (55–200) of the FMR1 gene can lead to Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders. These CGG repeats are translated into a toxic polyglycine-containing protein, FMRpolyG. Pathology of Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders comprises FMRpolyG- and p62-positive intranuclear inclusions. Diagnosing a FMR1-premutation carrier remains challenging, as the clinical features overlap with other neurodegenerative diseases. Here, we describe two male cases with Fragile X-associated neuropsychiatric disorders-related symptoms and mild movement disturbances and novel pathological features that can attribute to the variable phenotype. Macroscopically, both donors did not show characteristic white matter lesions on MRI; however, vascular infarcts in cortical- and sub-cortical regions were identified. Immunohistochemistry analyses revealed a high number of FMRpolyG intranuclear inclusions throughout the brain, which were also positive for p62. Importantly, we identified a novel pathological vascular phenotype with inclusions present in pericytes and endothelial cells. Although these results need to be confirmed in more cases, we propose that these vascular lesions in the brain could contribute to the complex symptomology of FMR1-premutation carriers. Overall, our report suggests that Fragile X-associated tremor/ataxia syndrome and Fragile X-associated neuropsychiatric disorders may present diverse clinical involvements resembling other types of dementia, and in the absence of genetic testing, FMRpolyG can be used post-mortem to identify premutation carriers.
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Affiliation(s)
- Anke A Dijkstra
- Department of Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centre, Amsterdam, The Netherlands
| | - Saif N Haify
- Department of Clinical Genetics, Erasmus MC, Rotterdam, The Netherlands
| | - Niek A Verwey
- Department of Neurology, Medisch Centrum Leeuwarden, Leeuwarden, The Netherlands
| | - Niels D Prins
- Department of Neurology, Alzheimer Center, VU University Medical Center, Amsterdam Neuroscience, The Netherlands.,Brain Research Center, Amsterdam, The Netherlands
| | | | - Annemieke J M Rozemuller
- Department of Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centre, Amsterdam, The Netherlands
| | - Marianna Bugiani
- Department of Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centre, Amsterdam, The Netherlands
| | - Wilfred F A den Dunnen
- Department of Pathology and Medical Biology, University Medical Center Groningen, Groningen, The Netherlands
| | - Peter K Todd
- Department of Neurology, University of Michigan, Ann Arbor, MI, USA.,Department of Veterans Affairs, Ann Arbor Healthcare System, Ann Arbor, MI, USA
| | - Nicolas Charlet-Berguerand
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR7104, University of Strasbourg, 67400, Illkirch, France
| | - Rob Willemsen
- Department of Clinical Genetics, Erasmus MC, Rotterdam, The Netherlands
| | - Renate K Hukema
- Department of Clinical Genetics, Erasmus MC, Rotterdam, The Netherlands.,Department of Health Care Studies, Rotterdam University of Applied Sciences, Rotterdam, The Netherlands
| | - Jeroen J M Hoozemans
- Department of Pathology, Amsterdam Neuroscience, Amsterdam University Medical Centre, Amsterdam, The Netherlands
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5
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Tassanakijpanich N, Cohen J, Cohen R, Srivatsa UN, Hagerman RJ. Cardiovascular Problems in the Fragile X Premutation. Front Genet 2020; 11:586910. [PMID: 33133171 PMCID: PMC7578382 DOI: 10.3389/fgene.2020.586910] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 09/21/2020] [Indexed: 12/12/2022] Open
Abstract
There is a dearth of information about cardiovascular problems in fragile X premutation carriers who have 55–200 CGG repeats in fragile X mental retardation 1 (FMR1) gene. The FMR1 expansion in the premutation range leads to toxic RNA gain-of-function resulting in cellular dysregulation. The mechanism of RNA toxicity underlies all of the premutation disorders including fragile X-associated tremor/ataxia syndrome, fragile X-associated primary ovarian insufficiency, and fragile X-associated neuropsychiatric disorder. Cardiovascular problems particularly autonomic dysfunction, hypertension, and cardiac arrhythmias are not uncommon in premutation carriers. Some arterial problems and valvular heart diseases have also been reported. This article reviews cardiovascular problems in premutation carriers and discusses possible contributing mechanisms including RNA toxicity and mild fragile X mental retardation protein deficiency. Further research studies are needed in order to prove a direct association of the cardiovascular problems in fragile X premutation carriers because such knowledge will lead to better preventative treatment.
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Affiliation(s)
- Nattaporn Tassanakijpanich
- UC Davis MIND Institute, UC Davis Health, Sacramento, CA, United States.,Department of Pediatrics, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Jonathan Cohen
- Fragile X Alliance Clinic, Genetic Clinics Australia, Melbourne, VIC, Australia
| | - Rashelle Cohen
- Fragile X Alliance Clinic, Genetic Clinics Australia, Melbourne, VIC, Australia
| | - Uma N Srivatsa
- Division of Cardiovascular Medicine, Department of Internal Medicine, UC Davis Medical Center, Sacramento, CA, United States
| | - Randi J Hagerman
- UC Davis MIND Institute, UC Davis Health, Sacramento, CA, United States.,Department of Pediatrics, University of California, Davis, Davis, School of Medicine, Sacramento, CA, United States
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6
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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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7
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Gabis LV, Shefer S, Raas-Rothschild A. Ethical Dilemmas Linked to Fragile X Testing of Minors—a Preliminary Survey Among Professionals. J Mol Neurosci 2020; 70:254-259. [DOI: 10.1007/s12031-019-01445-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 11/13/2019] [Indexed: 11/29/2022]
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8
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Zafarullah M, Tassone F. Molecular Biomarkers in Fragile X Syndrome. Brain Sci 2019; 9:E96. [PMID: 31035599 PMCID: PMC6562871 DOI: 10.3390/brainsci9050096] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 04/22/2019] [Accepted: 04/24/2019] [Indexed: 01/01/2023] Open
Abstract
Fragile X syndrome (FXS) is the most common inherited form of intellectual disability (ID) and a known monogenic cause of autism spectrum disorder (ASD). It is a trinucleotide repeat disorder, in which more than 200 CGG repeats in the 5' untranslated region (UTR) of the fragile X mental retardation 1 (FMR1) gene causes methylation of the promoter with consequent silencing of the gene, ultimately leading to the loss of the encoded fragile X mental retardation 1 protein, FMRP. FMRP is an RNA binding protein that plays a primary role as a repressor of translation of various mRNAs, many of which are involved in the maintenance and development of neuronal synaptic function and plasticity. In addition to intellectual disability, patients with FXS face several behavioral challenges, including anxiety, hyperactivity, seizures, repetitive behavior, and problems with executive and language performance. Currently, there is no cure or approved medication for the treatment of the underlying causes of FXS, but in the past few years, our knowledge about the proteins and pathways that are dysregulated by the loss of FMRP has increased, leading to clinical trials and to the path of developing molecular biomarkers for identifying potential targets for therapies. In this paper, we review candidate molecular biomarkers that have been identified in preclinical studies in the FXS mouse animal model and are now under validation for human applications or have already made their way to clinical trials.
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Affiliation(s)
- Marwa Zafarullah
- Department of Biochemistry and Molecular Medicine, University of California Davis, School of Medicine, Sacramento, 95817 CA, USA.
| | - Flora Tassone
- Department of Biochemistry and Molecular Medicine, University of California Davis, School of Medicine, Sacramento, 95817 CA, USA.
- MIND Institute, University of California Davis Medical Center, Sacramento, 95817 CA, USA.
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9
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Abstract
Individuals carrying an FMR1 expansion between 55 and 200 CGG repeats, are at risk of developing the Fragile X-associated tremor/ataxia syndrome (FXTAS), a late onset neurodegenerative disorder characterized by cerebellar gait ataxia, intentional tremor, neuropathy, parkinsonism, cognitive decline, and psychological disorders, such as anxiety and depression. In addition, brain atrophy, white matter disease, and hyperintensities of the middle cerebellar peduncles can also be present. The neuropathological distinct feature of FXTAS is represented by the presence of eosinophilic intranuclear inclusions in neurons and astrocytes throughout the brain and in other tissues. In this chapter, protocols for available diagnostic tools, in both humans and mice, the clinical features and the basic molecular mechanisms leading to FXTAS and the animal models proposed to study this disorder are discussed.
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10
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Famula JL, McKenzie F, McLennan YA, Grigsby J, Tassone F, Hessl D, Rivera SM, Martinez-Cerdeno V, Hagerman RJ. Presence of Middle Cerebellar Peduncle Sign in FMR1 Premutation Carriers Without Tremor and Ataxia. Front Neurol 2018; 9:695. [PMID: 30186228 PMCID: PMC6113389 DOI: 10.3389/fneur.2018.00695] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 07/31/2018] [Indexed: 11/23/2022] Open
Abstract
Here we report five cases of male FMR1 premutation carriers who present without clinical symptoms of the fragile X-associated tremor/ataxia syndrome (FXTAS), but who on MRI demonstrate white matter hyperintensities in the middle cerebellar peduncles (MCP sign) and other brain regions, a rare finding. MCP sign is the major radiological feature of FXTAS; it is therefore remarkable to identify five cases in which this MRI finding is present in the absence of tremor and ataxia, the major clinical features of FXTAS. Subjects underwent a detailed neurological evaluation, neuropsychological testing, molecular testing, and MRI evaluation utilizing T2 imaging described here. Additional white matter disease was present in the corpus callosum in four of the five cases. However, all cases were asymptomatic for motor signs of FXTAS.
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Affiliation(s)
- Jessica L Famula
- MIND Institute, University of California Davis Medical Center, Sacramento, CA, United States.,Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, United States
| | - Forrest McKenzie
- MIND Institute, University of California Davis Medical Center, Sacramento, CA, United States.,Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, United States
| | - Yingratana A McLennan
- MIND Institute, University of California Davis Medical Center, Sacramento, CA, United States.,Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, United States
| | - James Grigsby
- School of Medicine, University of Colorado, Denver, CO, United States
| | - Flora Tassone
- MIND Institute, University of California Davis Medical Center, Sacramento, CA, United States.,Department of Biochemistry and Molecular Medicine, University of California Davis School of Medicine, Sacramento, CA, United States
| | - David Hessl
- MIND Institute, University of California Davis Medical Center, Sacramento, CA, United States.,Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, CA, United States
| | - Susan M Rivera
- MIND Institute, University of California Davis Medical Center, Sacramento, CA, United States.,Department of Psychology, University of California Davis, Davis, CA, United States
| | - Veronica Martinez-Cerdeno
- MIND Institute, University of California Davis Medical Center, Sacramento, CA, United States.,Department of Pathology and Laboratory Medicine, Sacramento, CA, United States.,Institute for Pediatric Regenerative Medicine and Shriners Hospitals for Children Northern California, Sacramento, CA, United States
| | - Randi J Hagerman
- MIND Institute, University of California Davis Medical Center, Sacramento, CA, United States.,Department of Pediatrics, University of California Davis School of Medicine, Sacramento, CA, United States
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11
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Wheeler A, Raspa M, Hagerman R, Mailick M, Riley C. Implications of the FMR1 Premutation for Children, Adolescents, Adults, and Their Families. Pediatrics 2017; 139:S172-S182. [PMID: 28814538 PMCID: PMC5621635 DOI: 10.1542/peds.2016-1159d] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/24/2017] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND AND OBJECTIVES Given the nature of FMR1 gene expansions, most biological mothers, and often multiple other family members of children with fragile X syndrome (FXS), will have a premutation, which may increase individual and family vulnerabilities. This article summarizes important gaps in knowledge and notes potential implications for pediatric providers with regard to developmental and medical risks for children and adolescents with an FMR1 premutation, including possible implications into adulthood. METHODS A structured electronic literature search was conducted on FMR1 pre- and full mutations, yielding a total of 306 articles examined. Of these, 116 focused primarily on the premutation and are included in this review. RESULTS Based on the literature review, 5 topic areas are discussed: genetics and epidemiology; phenotypic characteristics of individuals with the premutation; implications for carrier parents of children with FXS; implications for the extended family; and implications for pediatricians. CONCLUSIONS Although the premutation phenotype is typically less severe in clinical presentation than in FXS, premutation carriers are much more common and are therefore more likely to be seen in a typical pediatric practice. In addition, there is a wide range of medical, cognitive/developmental, and psychiatric associated features that individuals with a premutation are at increased risk for having, which underscores the importance of awareness on the part of pediatricians in identifying and monitoring premutation carriers and recognizing the impact this identification may have on family members.
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Affiliation(s)
- Anne Wheeler
- RTI International, Research Triangle Park, North Carolina;
| | - Melissa Raspa
- RTI International, Research Triangle Park, North Carolina
| | - Randi Hagerman
- MIND Institute, University of California at Davis, Sacramento, California
| | - Marsha Mailick
- Waisman Center, University of Wisconsin-Madison, Madison, Wisconsin; and
| | - Catharine Riley
- National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, Georgia
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12
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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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13
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Molecular Correlates and Recent Advancements in the Diagnosis and Screening of FMR1-Related Disorders. Genes (Basel) 2016; 7:genes7100087. [PMID: 27754417 PMCID: PMC5083926 DOI: 10.3390/genes7100087] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2016] [Revised: 10/06/2016] [Accepted: 10/08/2016] [Indexed: 12/12/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common monogenic cause of intellectual disability and autism. Molecular diagnostic testing of FXS and related disorders (fragile X-associated primary ovarian insufficiency (FXPOI) and fragile X-associated tremor/ataxia syndrome (FXTAS)) relies on a combination of polymerase chain reaction (PCR) and Southern blot (SB) for the fragile X mental retardation 1 (FMR1) CGG-repeat expansion and methylation analyses. Recent advancements in PCR-based technologies have enabled the characterization of the complete spectrum of CGG-repeat mutation, with or without methylation assessment, and, as a result, have reduced our reliance on the labor- and time-intensive SB, which is the gold standard FXS diagnostic test. The newer and more robust triplet-primed PCR or TP-PCR assays allow the mapping of AGG interruptions and enable the predictive analysis of the risks of unstable CGG expansion during mother-to-child transmission. In this review, we have summarized the correlation between several molecular elements, including CGG-repeat size, methylation, mosaicism and skewed X-chromosome inactivation, and the extent of clinical involvement in patients with FMR1-related disorders, and reviewed key developments in PCR-based methodologies for the molecular diagnosis of FXS, FXTAS and FXPOI, and large-scale (CGG)n expansion screening in newborns, women of reproductive age and high-risk populations.
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14
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Lozano R, Saito N, Reed D, Eldeeb M, Schneider A, Hessl D, Tassone F, Beckett L, Hagerman R. Aging in Fragile X Premutation Carriers. CEREBELLUM (LONDON, ENGLAND) 2016; 15:587-94. [PMID: 27334385 PMCID: PMC8020959 DOI: 10.1007/s12311-016-0805-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
It is now recognized that FMR1 premutation carriers (PC) are at risk to develop a range of neurological, psychiatric, and immune-mediated disorders during adulthood. There are conflicting findings regarding the incidence of hypertension, hypothyroidism, diabetes, and cancer in these patients that warrant further study. A retrospective controlled study was performed in a convenience sample of 248 controls (130 men, 118 women) and 397 FMR1 PC with and without fragile X-associated tremor ataxia syndrome (FXTAS) (176 men, 221 women); all participants were at least 45 years old (men: mean 62.4, SD 9.5; women: mean 62.8, SD 9.9; p = 0.63). Memory and cognitive assessments (Wechsler Adult Intelligence Scale (WAIS-III), Wechsler Memory Scale (WMS-III)) and molecular testing (CGG repeats and FMR1-mRNA levels) were performed. Additional data included body mass index (BMI), cholesterol levels, blood pressure, hemoglobin A1c (HbA1c) levels, and medical history. A higher percentage of PC subjects self-reported having a diagnosis of hypertension (50.0 vs. 35.0 %, p = 0.006) and thyroid problems (20.4 vs. 10.0 %, p = 0.012) than control subjects. When comparing controls versus PC with FXTAS, the association was higher for diabetes (p = 0.043); however, the effect was not significant after adjusting for demographic predictors. Blood pressure, blood glucose levels, HbA1c, and BMI values were not significantly different between the two groups. The PC with FXTAS group performed consistently lower in neuropsychological testing compared with the PC without FXTAS group, but the differences were very small for all but the WAIS full-scale IQ. Based on these findings, it appears that the risk for hypertension, thyroid problems, and diabetes may be more frequent in PC with FXTAS, which will require verification in future studies.
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Affiliation(s)
- Reymundo Lozano
- Seaver Autism Center for Research and Treatment, Departments of Genetics and Genomic Sciences, Psychiatry, and Pediatrics, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, Box 1230, New York, NY, USA.
| | - Naomi Saito
- Department of Public Health Sciences, UC Davis School of Medicine, Sacramento, CA, USA
| | - Dallas Reed
- Departments of Genetics and Genomic Sciences and Obstetrics, Gynecology, and Reproductive Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Marwa Eldeeb
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute and Department of Pediatrics, UC Davis School of Medicine, Sacramento, CA, USA
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute and Department of Pediatrics, UC Davis School of Medicine, Sacramento, CA, USA
| | - David Hessl
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute and Department of Psychiatry, UC Davis School of Medicine, Sacramento, CA, USA
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute and Department of Psychiatry, UC Davis School of Medicine, Sacramento, CA, USA
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute and Department of Biochemistry, UC Davis School of Medicine, Sacramento, CA, USA
| | - Laurel Beckett
- Department of Public Health Sciences, UC Davis School of Medicine, Sacramento, CA, USA
| | - Randi Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute and Department of Pediatrics, UC Davis School of Medicine, Sacramento, CA, USA
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15
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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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16
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Lorefice L, Tranquilli S, Fenu G, Murru MR, Frau J, Rolesu M, Coghe GC, Marrosu F, Marrosu MG, Cocco E. A genetic study of the FMR1 gene in a Sardinian multiple sclerosis population. Neurol Sci 2015; 36:2213-20. [PMID: 26194536 DOI: 10.1007/s10072-015-2339-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Accepted: 07/13/2015] [Indexed: 02/04/2023]
Abstract
Multiple sclerosis (MS) is a complex autoimmune disease originated from the interplay between genetic and environmental factors. An overlap of clinical and neuroradiological parameters has been described between MS and an adult-onset neurodegenerative disorder, the fragile-X-associated tremor/ataxia syndrome (FXTAS). This syndrome is caused by a trinucleotide premutation expansion of a CGG sequence in the 55-200 repeat range, which is located in the fragile-X mental retardation 1 (FMR1) gene. Female premutation carriers have an increased propensity for immune-mediated disorders. Recently, a case of co-occurrence of MS and FXTAS was reported. Assuming that the premutation expansion may play a role in the MS susceptibility, we evaluated its frequency in a cohort of MS patients from Sardinia, an island characterized by a very high frequency of MS. Nuclear DNA was extracted by standard methods, purified with bisulfite treatment and then amplified twice by PCR with specific primers. Microsatellite analysis was performed and emizogotic subjects were sequenced. Clinical data of patients were also collected. Only 1/755 MS patients exhibited the premutation expansion with a heterozygosis pattern (30/58). No pathogenic repeat expansions (>200 repeats) were found in the entire cohort. Repeats labeled as the gray zone (45-60 repeats) were observed in 15/755 patients. No specific clinical features concerning disease course, disease activity, and disability were reported for these patients. Our results do not support a possible role for premutation or gray zone alleles in MS Sardinian patients. Further studies are needed to better understand the relationship between FXTAS and MS.
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Affiliation(s)
- L Lorefice
- Department of Public Health and Clinical and Molecular Medicine, Multiple Sclerosis Center, University of Cagliari, Ospedale "Binaghi", via Is Guadazzonis, 2, 09126, Cagliari, Italy.
| | - S Tranquilli
- Department of Medical Sciences, Institute of Neurology, University of Cagliari, Cagliari, Italy
| | - G Fenu
- Department of Public Health and Clinical and Molecular Medicine, Multiple Sclerosis Center, University of Cagliari, Ospedale "Binaghi", via Is Guadazzonis, 2, 09126, Cagliari, Italy
| | - M R Murru
- ASL8-Department of Medical Sciences, Multiple Sclerosis Center, University of Cagliari, Cagliari, Italy
| | - J Frau
- Department of Public Health and Clinical and Molecular Medicine, Multiple Sclerosis Center, University of Cagliari, Ospedale "Binaghi", via Is Guadazzonis, 2, 09126, Cagliari, Italy
| | - M Rolesu
- ASL8-Department of Medical Sciences, Multiple Sclerosis Center, University of Cagliari, Cagliari, Italy
| | - G C Coghe
- Department of Public Health and Clinical and Molecular Medicine, Multiple Sclerosis Center, University of Cagliari, Ospedale "Binaghi", via Is Guadazzonis, 2, 09126, Cagliari, Italy
| | - F Marrosu
- Department of Medical Sciences, Institute of Neurology, University of Cagliari, Cagliari, Italy
| | - M G Marrosu
- Department of Medical Sciences, Multiple Sclerosis Center, University of Cagliari, Cagliari, Italy
| | - E Cocco
- Department of Public Health and Clinical and Molecular Medicine, Multiple Sclerosis Center, University of Cagliari, Ospedale "Binaghi", via Is Guadazzonis, 2, 09126, Cagliari, Italy
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17
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Simplified strategy for rapid first-line screening of fragile X syndrome: closed-tube triplet-primed PCR and amplicon melt peak analysis. Expert Rev Mol Med 2015; 17:e7. [PMID: 25936533 PMCID: PMC4836207 DOI: 10.1017/erm.2015.5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Premutation and full-mutation hyperexpansion of CGG-triplets in the X-linked Fragile X Mental Retardation 1 (FMR1) gene have been implicated in fragile X-associated tremor/ataxia syndrome, fragile X-associated primary ovarian insufficiency, and fragile X syndrome (FXS), respectively. The currently available molecular diagnostic tests are either costly or labour-intensive, which prohibits their application as a first-line FMR1 test in large-scale population-based screening programs. In this study, we demonstrate the utility of a simplified closed-tube strategy for rapid first-line screening of FXS based on melt peak temperature (Tm) analysis of direct triplet-primed polymerase chain reaction amplicons (dTP-PCR MCA). In addition, we also evaluated the correlation between Tm and CGG-repeat size based on capillary electrophoresis (CE) of dTP-PCR amplicons. The assays were initially tested on 29 FMR1 reference DNA samples, followed by a blinded validation on 107 previously characterised patient DNA samples. The dTP-PCR MCA produced distinct melt profiles of higher Tm for samples carrying an expanded allele. Among the samples tested, we also observed a good correlation between Tm and CGG-repeat size. In the blinded validation study, dTP-PCR MCA accurately classified all normal and expansion carriers, and the FMR1 genotypic classification of all samples was completely concordant with the previously determined genotypes as well as the dTP-PCR CE results. This simple and cost-effective MCA-based assay may be useful as a first-line FXS screening tool that could rapidly screen out the large majority of unaffected individuals, thus minimising the number of samples that need to be analysed by Southern blot analysis.
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18
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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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19
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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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20
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Lozano R, Rosero CA, Hagerman RJ. Fragile X spectrum disorders. Intractable Rare Dis Res 2014; 3:134-46. [PMID: 25606363 PMCID: PMC4298643 DOI: 10.5582/irdr.2014.01022] [Citation(s) in RCA: 110] [Impact Index Per Article: 11.0] [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
The fragile X mental retardation 1 gene (FMR1), which codes for the fragile X mental retardation 1 protein (FMRP), is located at Xp27.3. The normal allele of the FMR1 gene typically has 5 to 40 CGG repeats in the 5' untranslated region; abnormal alleles of dynamic mutations include the full mutation (> 200 CGG repeats), premutation (55-200 CGG repeats) and the gray zone mutation (45-54 CGG repeats). Premutation carriers are common in the general population with approximately 1 in 130-250 females and 1 in 250-810 males, whereas the full mutation and Fragile X syndrome (FXS) occur in approximately 1 in 4000 to 1 in 7000. FMR1 mutations account for a variety of phenotypes including the most common monogenetic cause of inherited intellectual disability (ID) and autism (FXS), the most common genetic form of ovarian failure, the fragile X-associated primary ovarian insufficiency (FXPOI, premutation); and fragile X-associated tremor/ataxia syndrome (FXTAS, premutation). The premutation can also cause developmental problems including ASD and ADHD especially in boys and psychopathology including anxiety and depression in children and adults. Some premutation carriers can have a deficit of FMRP and some unmethylated full mutation individuals can have elevated FMR1 mRNA that is considered a premutation problem. Therefore the term "Fragile X Spectrum Disorder" (FXSD) should be used to include the wide range of overlapping phenotypes observed in affected individuals with FMR1 mutations. In this review we focus on the phenotypes and genotypes of children with FXSD.
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Affiliation(s)
- 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:
| | - Carolina Alba Rosero
- Instituto Colombiano del Sistema Nervioso, Clínica Montserrat, Bogotá D.C, Colombia
| | - Randi J Hagerman
- UC Davis MIND Institute and Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
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Hall DA, Birch RC, Anheim M, Jønch AE, Pintado E, O'Keefe J, Trollor JN, Stebbins GT, Hagerman RJ, Fahn S, Berry-Kravis E, Leehey MA. Emerging topics in FXTAS. J Neurodev Disord 2014; 6:31. [PMID: 25642984 PMCID: PMC4141265 DOI: 10.1186/1866-1955-6-31] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 04/23/2014] [Indexed: 02/07/2023] Open
Abstract
This paper summarizes key emerging issues in fragile X-associated tremor/ataxia syndrome (FXTAS) as presented at the First International Conference on the FMR1 Premutation: Basic Mechanisms & Clinical Involvement in 2013.
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Affiliation(s)
- Deborah A Hall
- Department of Neurological Sciences, Rush University, Chicago, IL, USA
| | - Rachael C Birch
- Department of Developmental Disability Neuropsychiatry, School of Psychiatry, University of New South Wales, Sydney, Australia
| | - Mathieu Anheim
- Département de Neurologie, Hôpitaux Universitaires de Strasbourg, Hôpital de Hautepierre, 67098 Strasbourg, Cedex, France ; Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM-U964/CNRS-UMR7104/Université de Strasbourg, 67404 Illkirch, France ; Fédération de Médecine Translationnelle de Strasbourg (FMTS), Université de Strasbourg, Strasbourg, France
| | - Aia E Jønch
- Department of clinical Genetics, Kennedy Center, Rigshospitalet, Copenhagen University Hospital, Copenhagen, Denmark
| | - Elizabeth Pintado
- Department of Medical Biochemistry and Molecular Biology, University of Seville, Sevilla, Spain
| | - Joanne O'Keefe
- Department of Anatomy & Cell Biology, Rush University, Chicago, IL, USA
| | - Julian N Trollor
- Department of Developmental Disability Neuropsychiatry, School of Psychiatry, University of New South Wales, Sydney, Australia ; Centre for Healthy Brain Ageing, University of New South Wales, Sydney, Australia
| | - Glenn T Stebbins
- Department of Neurological Sciences, Rush University, Chicago, IL, USA
| | - Randi J Hagerman
- Department of Pediatrics & M.I.N.D. Institute, University of California at Davis Medical Center, Sacramento, CA, USA
| | - Stanley Fahn
- Department of Neurology, Columbia University, New York, NY, USA
| | - Elizabeth Berry-Kravis
- Department of Neurological Sciences, Rush University, Chicago, IL, USA ; Departments of Pediatrics and Biochemistry, Rush University, Chicago, IL, USA
| | - Maureen A Leehey
- Department of Neurology, University of Colorado at Denver, Denver, CO, USA
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Visootsak J, Hipp H, Clark H, Berry-Kravis E, Anderson T, Laney D. Climbing the branches of a family tree: diagnosis of fragile X syndrome. J Pediatr 2014; 164:1292-5. [PMID: 24612903 PMCID: PMC4035419 DOI: 10.1016/j.jpeds.2014.01.051] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 12/30/2013] [Accepted: 01/24/2014] [Indexed: 11/18/2022]
Abstract
OBJECTIVE To determine the average number of family members diagnosed with a Fragile X Mental Retardation-1 (FMR1) mutation after a proband receives the initial diagnosis of fragile X syndrome (FXS). STUDY DESIGN We reviewed pedigrees of families who had been evaluated at the Fragile X Syndrome Center at Emory University in Atlanta, Georgia. Through these pedigrees, we determined the number of additional family members diagnosed as FMR1 premutation carriers or with full mutation FXS after the initial diagnosis in each proband. RESULTS The fragile X pedigree review identified 176 probands, including 108 males (61%) and 68 females (39%). A total of 785 family members were diagnosed with expanded fragile X alleles, including 278 males (35%) and 507 females (65%). These family members included 227 individuals with full mutation FXS (219 males and 8 females) and 558 premutation carriers (59 males and 499 females). After the initial diagnosis of a proband with FXS, on average at least 5 additional family members were diagnosed with an FMR1 mutation. CONCLUSION Our findings confirm that obtaining a detailed family history after diagnosis of a proband with FXS is likely to identify multiple family members with FMR1 mutations. It is important that the pediatrician or other health care provider making a diagnosis of FXS recognize the value of a detailed family history for timely diagnosis and treatment of additional individuals who may be FMR1 premutation carriers or have full mutation FXS.
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Affiliation(s)
| | - Heather Hipp
- Department of Human Genetics, Emory University, Atlanta, GA
| | - Heather Clark
- Department of Human Genetics, Emory University, Atlanta, GA
| | - Elizabeth Berry-Kravis
- Departments of Pediatrics, Neurological Sciences, and Biochemistry, Rush University Medical Center, Chicago, IL
| | - Tovi Anderson
- Department of Human Genetics, Emory University, Atlanta, GA
| | - Dawn Laney
- Department of Human Genetics, Emory University, Atlanta, GA
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Careaga M, Rose D, Tassone F, Berman RF, Hagerman R, Ashwood P. Immune dysregulation as a cause of autoinflammation in fragile X premutation carriers: link between FMRI CGG repeat number and decreased cytokine responses. PLoS One 2014; 9:e94475. [PMID: 24718368 PMCID: PMC3981824 DOI: 10.1371/journal.pone.0094475] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 03/16/2014] [Indexed: 12/31/2022] Open
Abstract
Background Increased rates of autoinflammatory and autoimmune disorders have been observed in female premutation carriers of CGG repeat expansion alleles of between 55–200 repeats in the fragile X mental retardation 1 (FMR1) gene. To determine whether an abnormal immune profile was present at a cellular level that may predispose female carriers to autoinflammatory conditions, we investigated dynamic cytokine production following stimulation of blood cells. In addition, splenocyte responses were examined in an FMR1 CGG knock-in mouse model of the fragile X premutation. Methods Human monocyte and peripheral blood leukocytes (PBLs) were isolated from the blood of 36 female FMR1 premutation carriers and 15 age-matched controls. Cells were cultured with media alone, LPS or PHA. In the animal model, splenocytes were isolated from 32 CGG knock-in mice and 32 wild type littermates. Splenocytes were cultured with media alone or LPS or PMA/Ionomycin. Concentrations of cytokines (GM-CSF, IL-1β, IL-6, IL-10, IL-13, IL-17, IFNγ, TNFα, and MCP-1) were determined from the supernatants of cellular cultures via Luminex multiplex assay. Additionally, phenotypic cellular markers were assessed on cells isolated from human subjects via flow cytometry. Results We found decreases in cytokine production in human premutation carriers as well as in the FMR1 knock-in mice when compared with controls. Levels of cytokines were found to be associated with CGG repeat length in both human and mouse. Furthermore, T cells from human premutation carriers showed decreases in cell surface markers of activation when compared with controls. Conclusions In this study, FMR1 CGG repeat expansions are associated with decreased immune responses and immune dysregulation in both humans and mice. Deficits in immune responses in female premutation carriers may lead to increased susceptibility to autoimmunity and further research is warranted to determine the link between FMR1 CGG repeat lengths and onset of autoinflammatory conditions.
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Affiliation(s)
- Milo Careaga
- Department of Medical Microbiology and Immunology, University of California Davis, Davis, California, United States of America
- The M.I.N.D. Institute, University of California Davis, Davis, California, United States of America
| | - Destanie Rose
- Department of Medical Microbiology and Immunology, University of California Davis, Davis, California, United States of America
- The M.I.N.D. Institute, University of California Davis, Davis, California, United States of America
| | - Flora Tassone
- The M.I.N.D. Institute, University of California Davis, Davis, California, United States of America
- Department of Biochemistry and Molecular Medicine, University of California Davis, Davis, California, United States of America
| | - Robert F. Berman
- The M.I.N.D. Institute, University of California Davis, Davis, California, United States of America
- Department of Neurological Surgery, University of California Davis, Davis, California, United States of America
| | - Randi Hagerman
- The M.I.N.D. Institute, University of California Davis, Davis, California, United States of America
- Department of Pediatrics University of California Davis, Davis, California, United States of America
| | - Paul Ashwood
- Department of Medical Microbiology and Immunology, University of California Davis, Davis, California, United States of America
- The M.I.N.D. Institute, University of California Davis, Davis, California, United States of America
- * E-mail:
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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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Lozano R, Hare EB, Hagerman RJ. Modulation of the GABAergic pathway for the treatment of fragile X syndrome. Neuropsychiatr Dis Treat 2014; 10:1769-79. [PMID: 25258535 PMCID: PMC4172237 DOI: 10.2147/ndt.s42919] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Fragile X syndrome (FXS) is the most common genetic cause of intellectual disability and the most common single-gene cause of autism. It is caused by mutations on the fragile X mental retardation gene (FMR1) and lack of fragile X mental retardation protein, which in turn, leads to decreased inhibition of translation of many synaptic proteins. The metabotropic glutamate receptor (mGluR) hypothesis states that the neurological deficits in individuals with FXS are due mainly to downstream consequences of overstimulation of the mGluR pathway. The main efforts have focused on mGluR5 targeted treatments; however, investigation on the gamma-aminobutyric acid (GABA) system and its potential as a targeted treatment is less emphasized. The fragile X mouse models (Fmr1-knock out) show decreased GABA subunit receptors, decreased synthesis of GABA, increased catabolism of GABA, and overall decreased GABAergic input in many regions of the brain. Consequences of the reduced GABAergic input in FXS include oversensitivity to sensory stimuli, seizures, and anxiety. Deficits in the GABA receptors in different regions of the brain are associated with behavioral and attentional processing deficits linked to anxiety and autistic behaviors. The understanding of the neurobiology of FXS has led to the development of targeted treatments for the core behavioral features of FXS, which include social deficits, inattention, and anxiety. These symptoms are also observed in individuals with autism and other neurodevelopmental disorders, therefore the targeted treatments for FXS are leading the way in the treatment of other neurodevelopmental syndromes and autism. The GABAergic system in FXS represents a target for new treatments. Herein, we discuss the animal and human trials of GABAergic treatment in FXS. Arbaclofen and ganaxolone have been used in individuals with FXS. Other potential GABAergic treatments, such as riluzole, gaboxadol, tiagabine, and vigabatrin, will be also discussed. Further studies are needed to determine the safety and efficacy of GABAergic treatments for FXS.
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Affiliation(s)
- Reymundo Lozano
- MIND Institute, UC Davis Medical Center, Sacramento, CA, USA ; Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
| | - Emma B Hare
- MIND Institute, UC Davis Medical Center, Sacramento, CA, USA ; Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
| | - Randi J Hagerman
- MIND Institute, UC Davis Medical Center, Sacramento, CA, USA ; Department of Pediatrics, UC Davis Medical Center, Sacramento, CA, USA
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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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Fragile X-associated tremor/ataxia syndrome (FXTAS): pathology and mechanisms. Acta Neuropathol 2013; 126:1-19. [PMID: 23793382 DOI: 10.1007/s00401-013-1138-1] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Accepted: 05/30/2013] [Indexed: 12/17/2022]
Abstract
Since its discovery in 2001, our understanding of fragile X-associated tremor/ataxia syndrome (FXTAS) has undergone a remarkable transformation. Initially characterized rather narrowly as an adult-onset movement disorder, the definition of FXTAS is broadening; moreover, the disorder is now recognized as only one facet of a much broader clinical pleiotropy among children and adults who carry premutation alleles of the FMR1 gene. Furthermore, the intranuclear inclusions of FXTAS, once thought to be a CNS-specific marker of the disorder, are now known to be widely distributed in multiple non-CNS tissues; this observation fundamentally changes our concept of the disease, and may provide the basis for understanding the diverse medical problems associated with the premutation. Recent work on the pathogenic mechanisms underlying FXTAS indicates that the origins of the late-onset neurodegenerative disorder actually lie in early development, raising the likelihood that all forms of clinical involvement among premutation carriers have a common underlying mechanistic basis. There has also been great progress in our understanding of the triggering event(s) in FXTAS pathogenesis, which is now thought to involve sequestration of one or more nuclear proteins involved with microRNA biogenesis. Moreover, there is mounting evidence that mitochondrial dysregulation contributes to the decreased cell function and loss of viability, evident in mice even during the neonatal period. Taken together, these recent findings offer hope for early interventions for FXTAS, well before the onset of overt disease, and for the treatment of other forms of clinical involvement among premutation carriers.
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Transmission of an FMR1 premutation allele in a large family identified through newborn screening: the role of AGG interruptions. J Hum Genet 2013; 58:553-9. [PMID: 23739124 DOI: 10.1038/jhg.2013.50] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 04/02/2013] [Accepted: 04/21/2013] [Indexed: 12/19/2022]
Abstract
The CGG repeat within the premutation range in the fragile X mental retardation 1 (FMR1) gene can lead to neurodegenerative disorders and intellectual disabilities. An increase in size upon the transmission from parent to child is more likely to occur for larger alleles and without AGG interruptions. We describe the molecular structure and the transmission of an FMR1 premutation allele in a multigenerational family, identified through newborn screening for fragile X syndrome. Transmission of the premutation allele was traced through five generations in 14 of the 23 individuals who were genotyped through cascade testing. Allele size instability during transmission was observed, but no expansions to a full mutation were detected. Clinical and molecular characterizations of the participants lead to the diagnosis of fragile X-associated tremor ataxia syndrome in one subject identified as a premutation carrier. A gradual small increase in the size of the premutation allele was observed during transmission through five generations. The relative stability is likely due to the presence of two AGGs within the allele. The detection of AGG interruptions within the premutation alleles is important in genetic counseling, to better predict the risk of expansion during transmission from a premutation to a full-mutation allele.
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29
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Au J, Akins RS, Berkowitz-Sutherland L, Tang HT, Chen Y, Boyd A, Tassone F, Nguyen DV, Hagerman R. Prevalence and risk of migraine headaches in adult fragile X premutation carriers. Clin Genet 2013; 84:546-51. [PMID: 23373759 DOI: 10.1111/cge.12109] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Revised: 01/21/2013] [Accepted: 01/21/2013] [Indexed: 12/19/2022]
Abstract
FMR1 premutation carriers are common in the general population (1/130-260 females and 1/250-810 males) and can be affected by fragile X-associated tremor ataxia syndrome, fragile X-associated primary ovarian insufficiency, anxiety, depression, hypertension, sleep apnea, fibromyalgia, and hypothyroidism. Here we report the results of a pilot study to assess the prevalence and risk of migraine in FMR1 premutation carriers. Three hundred fifteen carriers (203 females; 112 males) and 154 controls (83 females; 71 males) were seen sequentially as part of a family study. A standardized medical history, physical examination and confirmation of diagnosis of migraine headaches were performed by a physician. The prevalence of migraine was 54.2% in female carriers (mean age/SD: 49.60/13.73) and 26.79% in male carriers (mean age/SD: 59.94/14.27). This prevalence was higher compared to female (25.3%; mean age/SD: 47.60/15.21; p = 0.0001) and male controls (15.5%; mean age/SD; 53.88/13.31; p = 0.0406) who underwent the same protocol and were confirmed to be negative for the FMR1 mutation by DNA testing. We hypothesize that the increased prevalence of migraine headaches in FMR1 premutation carriers is likely related to the mitochondrial abnormalities that have recently been reported. Screening for migraine should be considered when evaluating FMR1 premutation carriers in the future.
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Affiliation(s)
- J Au
- Department of Pediatrics; M.I.N.D. Institute, University of California at Davis Medical Center, Sacramento, CA, USA
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Seritan AL, Ortigas M, Seritan S, Bourgeois JA, Hagerman RJ. PSYCHIATRIC DISORDERS ASSOCIATED WITH FXTAS. ACTA ACUST UNITED AC 2013; 9:59-64. [PMID: 25620899 DOI: 10.2174/157340013805289699] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Carriers of the FMR1 premutation (with 55-200 CGG repeats) may present with multiple medical and psychiatric disorders. Middle-aged carriers (males more often than females) may suffer from fragile X-associated tremor/ataxia syndrome (FXTAS). FXTAS is a newly discovered neurodegenerative disease characterized by intention tremor and ataxia, along with several other neurological features. Psychiatric manifestations are common in premutation carriers of both genders and include attention deficits, anxiety, depression, irritability, impulse dyscontrol, and substance abuse or dependence. Major depressive disorder, panic disorder with or without agoraphobia, generalized anxiety disorder, social phobia, and specific phobia are among the psychiatric diagnoses often encountered in premutation carriers, including those with FXTAS. Later in the course of the illness, cognitive deficits (including dementia) may occur. In this paper, we discuss common psychiatric phenotypes in FXTAS, based on a thorough review of the literature, as well as our own research experience. Symptomatic pharmacologic treatments are available, although disease modifying agents have not yet been developed.
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Affiliation(s)
- Andreea L Seritan
- Department of Psychiatry and Behavioral Sciences, University of California Davis Medical Center, Sacramento, California ; Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, University of California Davis Medical Center, Sacramento, California
| | - Melina Ortigas
- Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, University of California Davis Medical Center, Sacramento, California
| | - Stefan Seritan
- University of California Santa Barbara, College for Creative Studies, Santa Barbara, California
| | - James A Bourgeois
- Department of Psychiatry and Behavioural Neurosciences, McMaster University, Hamilton, Ontario, Canada
| | - Randi J Hagerman
- Medical Investigation of Neurodevelopmental Disorders (M.I.N.D.) Institute, University of California Davis Medical Center, Sacramento, California ; Department of Pediatrics, University of California Davis Medical Center, Sacramento, California
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Abstract
Complex caregiving issues occur in multigenerational families carrying the fragile X mutation and premutation. The same family members may care for children or siblings with fragile X syndrome (FXS) and for elderly parents with fragile X-associated tremor/ataxia syndrome (FXTAS). Family caregivers experience anxiety, depression, neglect of personal health care needs, employment difficulties, and loss of social support, leading to isolation and further psychiatric consequences. There is growing awareness of caregiver burden with regard to parents of children with FXS, but much less is known about the needs of informal caregivers of patients with FXTAS. In this paper, we review the available literature to date and provide suggestions for further exploration of caregivers' needs. Evidence-based strategies to address these needs are included. Many more research studies exploring caregiver burden in multigenerational fragile X families are needed, as well as studies aimed at investigating interventions and their impact on reduction.
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Affiliation(s)
- Ana-Maria Iosif
- Department of Public Health Sciences, University of California, Davis, Davis, California
| | - Andres F Sciolla
- Department of Psychiatry, University of California, San Diego, San Diego, California
| | - Khyati Brahmbhatt
- Department of Psychiatry and Behavioral Sciences, University of California, Davis Medical Center, Sacramento, California
| | - Andreea L Seritan
- Department of Psychiatry and Behavioral Sciences, University of California, Davis Medical Center, Sacramento, California
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Tassone F, Iong KP, Tong TH, Lo J, Gane LW, Berry-Kravis E, Nguyen D, Mu LY, Laffin J, Bailey DB, Hagerman RJ. FMR1 CGG allele size and prevalence ascertained through newborn screening in the United States. Genome Med 2012; 4:100. [PMID: 23259642 PMCID: PMC4064316 DOI: 10.1186/gm401] [Citation(s) in RCA: 217] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 11/19/2012] [Accepted: 12/21/2012] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Population screening for FMR1 mutations has been a topic of considerable discussion since the FMR1 gene was identified in 1991. Advances in understanding the molecular basis of fragile X syndrome (FXS) and in genetic testing methods have led to new, less expensive methodology to use for large screening endeavors. A core criterion for newborn screening is an accurate understanding of the public health burden of a disease, considering both disease severity and prevalence rate. This article addresses this need by reporting prevalence rates observed in a pilot newborn screening study for FXS in the US. METHODS Blood spot screening of 14,207 newborns (7,312 males and 6,895 females) was conducted in three birthing hospitals across the United States beginning in November 2008, using a PCR-based approach. RESULTS The prevalence of gray zone alleles was 1:66 females and 1:112 males, while the prevalence of a premutation was 1:209 females and 1:430 males. Differences in prevalence rates were observed among the various ethnic groups; specifically higher frequency for gray zone alleles in males was observed in the White group compared to the Hispanic and African-American groups. One full mutation male was identified (>200 CGG repeats). CONCLUSIONS The presented pilot study shows that newborn screening in fragile X is technically feasible and provides overall prevalence of the premutation and gray zone alleles in the USA, suggesting that the prevalence of the premutation, particularly in males, is higher than has been previously reported.
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Affiliation(s)
- Flora Tassone
- Department of Biochemistry and Molecular Medicine, UC Davis, Sacramento, CA 95817, USA
- MIND Institute, UC Davis Medical Center, Sacramento, CA 95817, USA
| | - Ka Pou Iong
- Department of Biochemistry and Molecular Medicine, UC Davis, Sacramento, CA 95817, USA
| | - Tzu-Han Tong
- Department of Biochemistry and Molecular Medicine, UC Davis, Sacramento, CA 95817, USA
| | - Joyce Lo
- Department of Biochemistry and Molecular Medicine, UC Davis, Sacramento, CA 95817, USA
| | - Louise W Gane
- MIND Institute, UC Davis Medical Center, Sacramento, CA 95817, USA
| | - Elizabeth Berry-Kravis
- Department of Pediatrics, Neurological Sciences, and Biochemistry, Rush University Medical Center, Chicago, IL 60612, USA
| | - Danh Nguyen
- Division of Biostatistics, UC Davis, Davis, CA 95616, USA
| | - Lisa Y Mu
- Division of Biostatistics, UC Davis, Davis, CA 95616, USA
| | - Jennifer Laffin
- Department of Pediatrics, University of Wisconsin, Madison, WI 53706, USA
| | - Don B Bailey
- RTI International, Research Triangle Park, NC 27709, USA
| | - Randi J Hagerman
- MIND Institute, UC Davis Medical Center, Sacramento, CA 95817, USA
- Department of Pediatrics, UC Davis, Sacramento, CA 95817, USA
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Sorensen PL, Gane LW, Yarborough M, Hagerman RJ, Tassone F. Newborn screening and cascade testing for FMR1 mutations. Am J Med Genet A 2012; 161A:59-69. [PMID: 23239591 DOI: 10.1002/ajmg.a.35680] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 08/20/2012] [Indexed: 12/12/2022]
Abstract
We describe an ongoing pilot project in which newborn screening (NBS) for FMR1 mutations and subsequent cascade testing are performed by the MIND Institute at the University of California, Davis Medical Center (UCDMC). To date, out of 3,042 newborns initially screened, 44 extended family members have been screened by cascade testing of extended family members once a newborn is identified. Fourteen newborns (7 males and 7 females) and 27 extended family members (5 males and 22 females) have been identified with FMR1 mutations. Three family histories are discussed in detail, each demonstrating some benefits and risks of NBS and cascade testing for FMR1 mutations in extended family members. While we acknowledge inherent risks, we propose that with genetic counseling, clinical follow-up of identified individuals and cascade testing, NBS has significant benefits. Treatment for individuals in the extended family who would otherwise not have received treatment can be beneficial. In addition, knowledge of carrier status can lead to lifestyle changes and prophylactic interventions that are likely to reduce the risk of late onset neurological or psychiatric problems in carriers. Also with identification of carrier family members through NBS, reproductive choices become available to those who would not have known that they were at risk to have offspring with fragile X syndrome.
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Affiliation(s)
- Page L Sorensen
- University of California Davis Medical Center, Sacramento, CA, USA
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Winarni TI, Chonchaiya W, Sumekar TA, Ashwood P, Morales GM, Tassone F, Nguyen DV, Faradz SMH, Van de Water J, Cook K, Hamlin A, Mu Y, Hagerman PJ, Hagerman RJ. Immune-mediated disorders among women carriers of fragile X premutation alleles. Am J Med Genet A 2012; 158A:2473-81. [PMID: 22903889 DOI: 10.1002/ajmg.a.35569] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2011] [Accepted: 06/20/2012] [Indexed: 12/14/2022]
Abstract
The relative risk of immune-mediated disorders (IMDs) among women carriers of premutation alleles is estimated by a survey for IMDs among 344 carrier women (age 19-81 years; mean 46.35 and SD 12.60) and 72 controls (age 18-87 years; mean 52.40 and SD 15.40). One hundred fifty four (44.77%) women carrier had at least one IMD, as did 20 controls (27.78%). Among women carriers, autoimmune thyroid disorder was the most common (24.4%), then fibromyalgia (10.2%), irritable bowel syndrome (IBS; 9.9%), Raynaud's phenomenon (7.6%), rheumatoid arthritis (RA; 3.8%), Sjögren syndrome (2.6%), systemic lupus erythematosus (SLE; 2.03%), multiple sclerosis (1.74%). Of 55 carriers age 40 or older with FXTAS, 72.73% had at least one IMD, compared to 46.54% of those without FXTAS (n = 159), and 31.58% of controls (n = 57). The estimated odds ratio (OR) for IMD is 2.6 (95% CI 1.2-5.6, P = 0.015) for women with FXTAS relative to those without FXTAS; the likelihood of IMD in carriers without or with FXTAS was also significantly higher than for controls (OR 2.1, 95% CI 1.1-4.2, P = 0.034; OR 5.5, 95% CI 2.4-12.5, P < 0.001, respectively). Similarly, the odds of having an IMD among carriers with FXPOI is about 2.4 times higher when compared to carriers without FXPOI (95% CI 1.1-5.0; P = 0.021). The likelihood of IMD in carriers with or without FXPOI is greater (OR 2.4, 95% CI 1.1-5.0; P = 0.021) compared to that of controls.
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Affiliation(s)
- Tri Indah Winarni
- Medical Investigation of Neurodevelopmental Disorders Institute, University of California, Davis, Health System, Sacramento, USA
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Winarni TI, Mundhofir FEP, Ediati A, Belladona M, Nillesen WM, Yntema HG, Hamel BCJ, Faradz SMH, Hagerman RJ. The fragile X-associated tremor ataxia syndrome (FXTAS) in Indonesia. Clin Genet 2012; 83:263-8. [PMID: 22568721 DOI: 10.1111/j.1399-0004.2012.01899.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 05/04/2012] [Indexed: 11/29/2022]
Abstract
Fragile X-associated disorders caused by the premutation of the FMR1 gene, includes the fragile X-associated tremor/ataxia syndrome (FXTAS). FXTAS affects more than 40% of premutation males over the age of 50 and 75% over the age of 80. FMR1 molecular analysis was done using PCR and confirmed by Southern Blot. Three premutation males were diagnosed FXTAS using quantification based on the standard neurological examination. Cognitive impairment was assessed using Raven and WAIS-R test. MRI was done to identify the middle cerebellar peduncle (MCP) sign, white matter disease and/or cerebral atrophy. Three cases of FXTAS are identified, of five individuals older than 50 years in one family tree two met criteria for definite FXTAS and the third with sub-clinical symptoms, although cognitive and radiological criteria are met. These cases are the first identified FXTAS cases in rural Indonesia. In addition with lack of routine medical follow-up, complications of FXTAS, such as hypertension may go unrecognized and untreated, which may further exacerbate the central nervous system (CNS) findings of FXTAS.
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Affiliation(s)
- T I Winarni
- Division of Human Genetic Center for Biomedical Research, Faculty of Medicine, Diponegoro University, Semarang, Indonesia
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