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Rolle-McFarland D, Liu Y, Mostafaei F, Zauber SE, Zhou Y, Li Y, Fan Q, Zheng W, Nie LH, Wells EM. The association of bone and blood manganese with motor function in Chinese workers. Neurotoxicology 2022; 88:224-230. [PMID: 34896555 PMCID: PMC8748420 DOI: 10.1016/j.neuro.2021.12.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 12/07/2021] [Accepted: 12/08/2021] [Indexed: 01/03/2023]
Abstract
Manganese (Mn) is an essential element. However, Mn overexposure is associated with motor dysfunction. This cross-sectional study assessed the association between bone Mn (BnMn) and whole blood Mn (BMn) with motor function in 59 Chinese workers. BnMn and BMn were measured using a transportable in vivo neutron activation analysis system and inductively coupled plasma mass spectrometry, respectively. Motor function (manual coordination, postural sway, postural hand tremor, and fine motor function) was assessed using the Coordination Ability Test System (CATSYS) and the Purdue Pegboard. Relationships between Mn biomarkers and motor test scores were analyzed with linear regression models adjusted for age, education, current employment, and current alcohol consumption. BMn was significantly inversely associated with hand tremor intensity (dominant hand (β=-0.04, 95 % confidence interval (CI):-0.07, -0.01; non-dominant hand β=-0.05, 95 % CI:-0.08, -0.01) hand tremor center frequency (non-dominant hand β=-1.61, 95 % CI:-3.03, -0.19) and positively associated with the Purdue Pegboard Assembly Score (β = 4.58, 95 % CI:1.08, 8.07). BnMn was significantly inversely associated with finger-tapping performance (non-dominant hand β=-0.02, 95 % CI:-0.04,-0.004), mean sway (eyes closed and foam β=-0.68, 95 % CI:-1.31,-0.04), and positively associated with hand tremor center frequency (dominant hand, β = 0.40, 95 % CI:0.002, 0.80). These results suggest BMn is related to better postural hand tremor and fine motor control and BnMn is related to worse motor coordination and postural hand tremor but better (i.e., less) postural sway. The unexpected positive results might be explained by choice of biomarker or confounding by work-related motor activities. Larger, longitudinal studies in this area are recommended.
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Affiliation(s)
- Danelle Rolle-McFarland
- School of Health Sciences, Purdue University, West
Lafayette, IN, USA.,OncoSynergy, Inc., Greenwich, CT, USA
| | - Yingzi Liu
- School of Health Sciences, Purdue University, West
Lafayette, IN, USA.,Department of Radiation Oncology, School of Medicine, Emory
University, Atlanta, GA, USA
| | - Farshad Mostafaei
- School of Health Sciences, Purdue University, West
Lafayette, IN, USA.,Department of Radiation Oncology, Augusta University,
Medical College of Georgia, Augusta, USA
| | - S. Elizabeth Zauber
- Department of Neurology, Indiana University School of
Medicine, Indianapolis, IN, USA
| | - Yuanzhong Zhou
- School of Public Health, Zunyi Medical University, Zunyi,
Guizhou, China
| | - Yan Li
- School of Public Health, Zunyi Medical University, Zunyi,
Guizhou, China
| | - Quiyan Fan
- Zunyi Medical and Pharmaceutical College, Zunyi, Guizhou,
China
| | - Wei Zheng
- School of Health Sciences, Purdue University, West
Lafayette, IN, USA
| | - Linda H. Nie
- School of Health Sciences, Purdue University, West
Lafayette, IN, USA
| | - Ellen M. Wells
- School of Health Sciences, Purdue University, West
Lafayette, IN, USA.,Corresponding author: Address: 550
Stadium Mall Drive; West Lafayette, IN 47907; USA, Phone: 1-765-496-3535,
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O'Keeffe C, Dominguez MC, O'Rourke E, Lynch T, Reilly RB. Decreased Theta Power Reflects Disruption in Postural Control Networks of Fragile X Premutation Carriers . ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:2845-2848. [PMID: 33018599 DOI: 10.1109/embc44109.2020.9176289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
FRM1 premutation carriers exhibit various subtle deficits in balance and stability, prior to the development of the movement disorder Fragile X Associated Tremor/Ataxia Syndrome (FXTAS). Force plate posturography has increasingly been combined with the temporal sensitive imaging methods such as EEG to offer insight into the neural mechanisms which govern postural control. This study investigated cortical theta power during continuous balance and its relationship to balance performance in Fragile X premutation carriers. Eight premutation carriers and 6 controls stood on a force platform under altered sensory and cognitive conditions while postural sway and high-density EEG data were simultaneously recorded. Carriers exhibited greater sway area when sensory input was reduced (p=0.01) and cognitive load was increased (p=0.01), as well as significantly reduced frontal theta power compared to the Control Group. The relationship between theta power and postural control seen in the control group may indicate an increase in error detection caused by reduced visual input and greater discrepancies between expected and actual balance state. While the lower theta power in frontal regions of carriers may indicate a disruption in neural networks underpinning postural control. Such results provide new insight into the neural correlates of balance control in Fragile X premutation carriers.
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O'Keeffe C, Taboada LP, Feerick N, Gallagher L, Lynch T, Reilly RB. Complexity based measures of postural stability provide novel evidence of functional decline in fragile X premutation carriers. J Neuroeng Rehabil 2019; 16:87. [PMID: 31299981 PMCID: PMC6624948 DOI: 10.1186/s12984-019-0560-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 06/26/2019] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Fragile X Associated Tremor/Ataxia Syndrome (FXTAS) is a neurodegenerative movement disorder characterized by tremor, ataxic gait, and balance issues resulting from a premutation of the Fragile X Mental Retardation 1 (FMR1) gene. No biomarkers have yet been identified to allow early diagnosis of FXTAS, however, recent studies have reported subtle issues in the stability of younger premutation carriers, before disease onset. This study investigates the efficacy of multiscale entropy analysis (MSE) in detecting early changes in the motor system of premutation carriers without FXTAS. METHODS Sway complexity of 12 female Premutation carriers and 15 healthy Controls were measured under four conditions: eyes open, closed, and two dual-task conditions. A Sustained Attention Response Task (SART) and a working memory based N-Back task were employed to increase cognitive load while standing on the forceplate. A Complexity Index (Ci) was calculated for anterior-posterior (AP) and mediolateral (ML) sway. Independent t-tests were used to assess between-group differences and Oneway repeated measures ANOVA were used to assess within group differences with Bonferroni corrections to adjust for multiple comparisons. RESULTS Group performances were comparable with eyes open and closed conditions. The Carrier group's Ci was consistent across tasks and conditions while the Control group's AP Ci increased significantly during the cognitive dual-task (p = 0.001). There was also a strong correlation between CGG repeat length and complexity for the Carrier group (p = 0.004). SIGNIFICANCE Increased sway complexity is believed to stem from reallocation of attention to facilitate the increased cognitive demands of dual-tasks. Carriers' complexity did not change during dual-tasks, possibly indicating capacity interference and inefficient division of attention. Lower sway complexity in carriers suggests diminished adaptive capacity under stress as well as degradation of motor functioning. Therefore, sway complexity may be a useful tool in identifying early functional decline in FMR1 premutation carriers as well as monitoring progression towards disease onset.
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Affiliation(s)
- Clodagh O'Keeffe
- Trinity Centre for Biomedical Engineering, Trinity College, The University of Dublin, 152 - 160 Pearse St, Dublin 2, Ireland. .,School of Medicine, Trinity College, The University of Dublin, Dublin, Ireland.
| | - Laura P Taboada
- Trinity Centre for Biomedical Engineering, Trinity College, The University of Dublin, 152 - 160 Pearse St, Dublin 2, Ireland.,School of Engineering, Trinity College, The University of Dublin, Dublin, Ireland
| | - Niamh Feerick
- Trinity Centre for Biomedical Engineering, Trinity College, The University of Dublin, 152 - 160 Pearse St, Dublin 2, Ireland.,School of Medicine, Trinity College, The University of Dublin, Dublin, Ireland
| | - Louise Gallagher
- School of Medicine, Trinity College, The University of Dublin, Dublin, Ireland.,Department of Psychiatry, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Timothy Lynch
- The Dublin Neurological Institute at the Mater Misericordiae University Hospital, Dublin, Ireland.,Centre for Neuroscience, Conway Institute, University College Dublin, Dublin, Ireland.,Mater Misericordiae University Hospital, Dublin, Ireland
| | - Richard B Reilly
- Trinity Centre for Biomedical Engineering, Trinity College, The University of Dublin, 152 - 160 Pearse St, Dublin 2, Ireland.,School of Medicine, Trinity College, The University of Dublin, Dublin, Ireland.,School of Engineering, Trinity College, The University of Dublin, Dublin, Ireland
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Wang Z, Khemani P, Schmitt LM, Lui S, Mosconi MW. Static and dynamic postural control deficits in aging fragile X mental retardation 1 (FMR1) gene premutation carriers. J Neurodev Disord 2019; 11:2. [PMID: 30665341 PMCID: PMC6341725 DOI: 10.1186/s11689-018-9261-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 12/26/2018] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Individuals with premutation alleles of the fragile X mental retardation 1 (FMR1) gene are at risk of developing fragile X-associated tremor/ataxia syndrome (FXTAS) during aging. Characterization of motor issues associated with aging in FMR1 premutation carriers is needed to determine neurodegenerative processes and establish new biobehavioral indicators to help identify individuals at greatest risk of developing FXTAS. METHODS We examined postural stability in 18 premutation carriers ages 46-77 years and 14 age-matched healthy controls. Participants completed a test of static stance and two tests of dynamic postural sway on a force platform to quantify postural variability and complexity. CGG repeat length was measured for each premutation carrier, and MRI and neurological evaluations were conducted to identify carriers who currently met criteria for FXTAS. Of the 18 premutation carriers, seven met criteria for definite/probable FXTAS (FXTAS+), seven showed no MRI or neurological signs of FXTAS (FXTAS-), and four were inconclusive due to insufficient data. RESULTS Compared to controls, premutation carriers showed increased center of pressure (COP) variability in the mediolateral (COPML) direction during static stance and reduced COP variability in the anterior-posterior (COPAP) direction during dynamic AP sway. They also showed reductions in COPML complexity during each postural condition. FXTAS+ individuals showed reduced COPAP variability compared to FXTAS- carriers and healthy controls during dynamic AP sway. Across all carriers, increased sway variability during static stance and decreased sway variability in target directions during dynamic sways were associated with greater CGG repeat length and more severe neurologically rated posture and gait abnormalities. CONCLUSION Our findings indicate that aging FMR1 premutation carriers show static and dynamic postural control deficits relative to healthy controls implicating degenerative processes of spinocerebellar and cerebellar-brainstem circuits that may be independent of or precede the onset of FXTAS. Our finding that FXTAS+ and FXTAS- premutation carriers differed on their level of intentional AP sway suggests that neural mechanisms of dynamic postural control may be differentially impacted in patients with FXTAS, and its measurement may be useful for rapidly and precisely identifying disease presence and onset.
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Affiliation(s)
- Zheng Wang
- Department of Occupational Therapy, University of Florida, Gainesville, FL, 32611, USA. .,University of Florida, 1225 Center Drive, PO Box 100164, Gainesville, FL, 326100164, USA.
| | - Pravin Khemani
- Department of Neurology, Swedish Neuroscience Institute, Seattle, WA, 98121, USA
| | - Lauren M Schmitt
- Division of Developmental and Behavioral Pediatrics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, 45229, USA
| | - Su Lui
- Huaxi Magnetic Resonance Research Center (HMRRC), Department of Radiology, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
| | - 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
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Pereverzeva DS, Tyushkevich SA, Gorbachevskaya NL, Mamokhina UA, Danilina KK. Heterogeneity of clinical characteristics of FMR1-related disorders. Zh Nevrol Psikhiatr Im S S Korsakova 2019; 119:103-111. [DOI: 10.17116/jnevro2019119071103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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6
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Al Olaby RR, Tang HT, Durbin-Johnson B, Schneider A, Hessl D, Rivera SM, Tassone F. Assessment of Molecular Measures in Non-FXTAS Male Premutation Carriers. Front Genet 2018; 9:302. [PMID: 30186307 PMCID: PMC6113865 DOI: 10.3389/fgene.2018.00302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 07/17/2018] [Indexed: 11/26/2022] Open
Abstract
Approximately 30-40% of male and 8-16% of female carriers of the Fragile X premutation will develop a neurodegenerative movement disorder characterized by intentional tremor, gait ataxia, autonomic dysfunction, cognitive decline, and Parkinsonism during their lifetime. At the molecular level, premutation carriers have increased expression levels of the FMR1 and the antisense FMR1 (ASFMR1) mRNAs. Both genes undergo alternative splicing giving rise to a number of different transcripts. Alteration in the alternative splicing process might be associated with FXTAS. In this study, we have investigated the correlation between objective measures of movement (balance and tremor using the CATSYS battery) and the expression of both the FMR1 and the ASFMR1 genes. In addition, we investigated whether their expression level and that of the ASFMR1 131 bp splice isoform could distinguish between premutation carriers with FXTAS and non-FXTAS premutation carriers. Confirming previous findings, the expression levels of transcripts at the FMR1 locus positively correlated with the CGG repeat number and significantly differentiated the premutation carriers from the control groups. Furthermore, premutation carriers with and without FXTAS, showed a significant difference in the expression level of the ASFMR1 131 bp splice isoform when compared to age and gender matched controls. However, there was no significant difference in the ASFMR1 131 bp splice isoform expression level when comparing premutation carriers with and without FXTAS. Finally, our results indicate significant group differences in CATSYS dominant hand reaction time and postural sway with eyes closed in premutation carriers without FXTAS compared to controls. In addition, a significant inverse association between the tremor intensity and the expression level of ASFMR1 131 bp splice isoform in premutation carriers compared to controls, was observed, suggesting a potential role in the pathogenesis of FXTAS.
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Affiliation(s)
- Reem R. Al Olaby
- Department of Biochemistry and Molecular Medicine, UC Davis Medical Center, University of California, Davis, Davis, CA, United States
| | - Hiu-Tung Tang
- Department of Biochemistry and Molecular Medicine, UC Davis Medical Center, University of California, Davis, Davis, CA, United States
| | - Blythe Durbin-Johnson
- Department of Biostatistics, University of California, Davis, Davis, CA, United States
| | - Andrea Schneider
- Department of Pediatrics, UC Davis Medical Center, University of California, Davis, Davis, CA, United States
- MIND Institute, UC Davis Medical Center, Sacramento, CA, United States
| | - David Hessl
- MIND Institute, UC Davis Medical Center, Sacramento, CA, United States
- Department of Psychiatry and Behavioral Sciences, UC Davis Medical Center, University of California, Davis, Davis, CA, United States
| | - Susan M. Rivera
- Department of Psychiatry and Behavioral Sciences, UC Davis Medical Center, University of California, Davis, Davis, CA, United States
- Neurocognitive Development Lab, Department of Psychology, UC Davis Center for Mind and Brain, University of California, Davis, Davis, CA, United States
| | - Flora Tassone
- Department of Biochemistry and Molecular Medicine, UC Davis Medical Center, University of California, Davis, Davis, CA, United States
- Department of Pediatrics, UC Davis Medical Center, University of California, Davis, Davis, CA, United States
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7
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Abstract
The FMR1 premutation confers a 40–60% risk for males of developing a neurodegenerative disease called the Fragile X-associated Tremor Ataxia Syndrome (FXTAS). FXTAS is a late-onset disease that primarily involves progressive symptoms of tremor and ataxia, as well as cognitive decline that can develop into dementia in some patients. At present, it is not clear whether changes to brain function are detectable in motor regions prior to the onset of frank symptomatology. The present study therefore aimed to utilize an fMRI motor task for the first time in an asymptomatic premutation population. Premutation carriers without a diagnosis of FXTAS (n = 17) and a group of healthy male controls (n = 17), with an age range of 24–68 years old, were recruited for this cross-sectional study. This study utilized neuroimaging, molecular and clinical measurements, employing an fMRI finger-tapping task with a block design consisting of sequential finger-tapping, random finger-tapping and rest conditions. The imaging analysis contrasted the sequential and random conditions to investigate activation changes in response to a change in task demand. Additionally, measurements were obtained of participant tremor, co-ordination and balance using the CATSYS-2000 system and measures of FMR1 mRNA were quantified from peripheral blood samples using quantitative real-time PCR methodology. Premutation carriers demonstrated significantly less cerebellar activation than controls during sequential versus random finger tapping (FWEcorr < 0.001). In addition, there was a significant age by group interaction in the hippocampus, inferior parietal cortex and temporal cortex originating from a more negative relationship between brain activation and age in the carrier group compared to the controls (FWEcorr < 0.001). Here, we present for the first time functional imaging-based evidence for early movement-related neurodegeneration in Fragile X premutation carriers. These changes pre-exist the diagnosis of FXTAS and are greatest in older carriers suggesting that they may be indicative of FXTAS vulnerability. The authors present a cross-sectional fMRI study in male carriers of the FMR1 premutation Carriers show decreased BOLD activation at the cerebellum in response to change in task demand in a finger-tapping task Carriers exhibit a group x age interaction of BOLD response in the temporoparietal area These changes pre-exist the diagnosis of the Fragile X-associated Tremor/Ataxia Syndrome (FXTAS)
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O'Keefe JA, Robertson-Dick EE, Hall DA, Berry-Kravis E. Gait and Functional Mobility Deficits in Fragile X-Associated Tremor/Ataxia Syndrome. THE CEREBELLUM 2017; 15:475-82. [PMID: 26298472 DOI: 10.1007/s12311-015-0714-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) results from a "premutation" (PM) size CGG repeat expansion in the fragile X mental retardation 1 (FMR1) gene. Cerebellar gait ataxia is the primary feature in some FXTAS patients causing progressive disability. However, no studies have quantitatively characterized gait and mobility deficits in FXTAS. We performed quantitative gait and mobility analysis in seven FMR1 PM carriers with FXTAS and ataxia, six PM carriers without FXTAS, and 18 age-matched controls. We studied four independent gait domains, trunk range of motion (ROM), and movement transitions using an instrumented Timed Up and Go (i-TUG). We correlated these outcome measures with FMR1 molecular variables and clinical severity scales. PM carriers with FXTAS were globally impaired in every gait performance domain except trunk ROM compared to controls. These included total i-TUG duration, stride velocity, gait cycle time, cadence, double-limb support and swing phase times, turn duration, step time before turn, and turn-to-sit duration, and increased gait variability on several measures. Carriers without FXTAS did not differ from controls on any parameters, but double-limb support time was close to significance. Balance and disability scales correlated with multiple gait and movement transition parameters, while the FXTAS Rating Scale did not. This is the first study to quantitatively examine gait and movement transitions in FXTAS patients. Gait characteristics were consistent with those from previous cohorts with cerebellar ataxia. Sensitive measures like the i-TUG may help determine efficacy of interventions, characterize disease progression, and provide early markers of disease in FXTAS.
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Affiliation(s)
- Joan A O'Keefe
- Department of Anatomy and Cell Biology, Rush University Medical Center, 600 South Paulina Street, Office 505B, Chicago, IL, 60612, USA.
| | - Erin E Robertson-Dick
- Department of Anatomy and Cell Biology, Rush University Medical Center, 600 South Paulina Street, Office 505B, Chicago, IL, 60612, USA
| | - Deborah A Hall
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA
| | - Elizabeth Berry-Kravis
- Department of Neurological Sciences, Rush University Medical Center, Chicago, IL, USA.,Department of Pediatrics, Rush University Medical Center, Chicago, IL, USA.,Department of Biochemistry, Rush University Medical Center, Chicago, IL, USA
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9
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Gossett A, Sansone S, Schneider A, Johnston C, Hagerman R, Tassone F, Rivera SM, Seritan AL, Hessl D. Psychiatric disorders among women with the fragile X premutation without children affected by fragile X syndrome. Am J Med Genet B Neuropsychiatr Genet 2016; 171:1139-1147. [PMID: 27615674 PMCID: PMC6907071 DOI: 10.1002/ajmg.b.32496] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 08/19/2016] [Indexed: 11/07/2022]
Abstract
Several studies have demonstrated increased rates of anxiety and depressive disorders among female carriers of the fragile X premutation. However, the majority of these studies focused on mothers of children with fragile X syndrome, who experience higher rates of parenting stress that may contribute to the emergence of these disorders. The present study compared psychiatric symptom presentation (utilizing measures of current symptoms and lifetime DSM-IV Axis I disorders) in 24 female carriers without affected children (mean age = 32.1 years) to 26 non-carrier women from the community (mean age = 30.5 years). We also examined the association between CGG repeat size (adjusted for X activation ratio) and mRNA, with severity of psychiatric symptoms. Women with the premutation reported significantly elevated symptoms of anxiety, depression, interpersonal sensitivity, obsessive-compulsiveness, and somatization relative to controls during the past week. Carriers had significantly higher rates of lifetime social phobia (42.3%) compared to controls (12.5%); however, this comparison did not remain significant after multiple comparison adjustment. Rates of other psychiatric disorders were not significantly elevated relative to controls, though it should be noted that lifetime rates among controls were much higher than previously published population estimates. Although the sample is relatively small, the study of this unique cohort suggests the premutation confers risk for mood and anxiety disorders independent of the stress of parenting children with FXS. Screening for psychiatric disorders in women with the premutation, even before they become parents, is important and highly encouraged. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Amy Gossett
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Psychology, California School of Professional Psychology, Alliant International University, Sacramento, California
| | - Stephanie Sansone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, California
| | - Cindy Johnston
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California
| | - Randi Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Pediatrics, University of California Davis School of Medicine, Sacramento, California
| | - Flora Tassone
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Biochemistry and Molecular Medicine, University of California Davis, Davis, California
| | - Susan M. Rivera
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Psychology, University of California Davis, Davis, California
- Center for Mind and Brain, University of California Davis, Davis, California
| | - Andreea L. Seritan
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California
| | - David Hessl
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, California
- Department of Psychiatry and Behavioral Sciences, University of California Davis School of Medicine, Sacramento, California
- Correspondence to: David Hessl, Ph.D., Department of Psychiatry and Behavioral Sciences, MIND Institute, UC Davis, 2825 50th St., Sacramento, CA 95817.
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10
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Foote M, Arque G, Berman RF, Santos M. Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS) Motor Dysfunction Modeled in Mice. CEREBELLUM (LONDON, ENGLAND) 2016; 15:611-22. [PMID: 27255703 PMCID: PMC5014696 DOI: 10.1007/s12311-016-0797-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is a late-onset neurodegenerative disorder that affects some carriers of the fragile X premutation (PM). In PM carriers, there is a moderate expansion of a CGG trinucleotide sequence (55-200 repeats) in the fragile X gene (FMR1) leading to increased FMR1 mRNA and small to moderate decreases in the fragile X mental retardation protein (FMRP) expression. The key symptoms of FXTAS include cerebellar gait ataxia, kinetic tremor, sensorimotor deficits, neuropsychiatric changes, and dementia. While the specific trigger(s) that causes PM carriers to progress to FXTAS pathogenesis remains elusive, the use of animal models has shed light on the underlying neurobiology of the altered pathways involved in disease development. In this review, we examine the current use of mouse models to study PM and FXTAS, focusing on recent advances in the field. Specifically, we will discuss the construct, face, and predictive validities of these PM mouse models, the insights into the underlying disease mechanisms, and potential treatments.
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Affiliation(s)
- Molly Foote
- Department of Neurological Surgery, University of California, Davis, CA, USA.
| | - Gloria Arque
- Department of Molecular Neuroscience, Medical University of Vienna, Vienna, Austria
| | - Robert F Berman
- Department of Neurological Surgery, University of California, Davis, CA, USA
| | - Mónica Santos
- Institute of Biology, Otto-von-Guericke University, Magdeburg, Germany
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11
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Characterization and Early Detection of Balance Deficits in Fragile X Premutation Carriers With and Without Fragile X-Associated Tremor/Ataxia Syndrome (FXTAS). THE CEREBELLUM 2016; 14:650-62. [PMID: 25763861 DOI: 10.1007/s12311-015-0659-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) results from a "premutation" size 55-200 CGG repeat expansion in the fragile X mental retardation 1 (FMR1) gene. Core motor features include cerebellar gait ataxia and kinetic tremor, resulting in progressive mobility disability. There are no published studies characterizing balance deficits in FMR1 premutation carriers with and without FXTAS using a battery of quantitative measures to test the sensory integration underlying postural control, automatic postural reflexes, and dynamic postural stability limits. Computerized dynamic posturography (CDP) and two performance-based balance measures were administered in 44 premutation carriers, 21 with FXTAS and 23 without FXTAS, and 42 healthy controls to compare balance and functional mobility between these groups. Relationships between FMR1 molecular variables, age, and sex and CDP scores were explored. FXTAS subjects demonstrated significantly lower scores on the sensory organization test (with greatest reductions in the vestibular control of balance), longer response latencies to balance perturbations, and reduced stability limits compared to controls. Premutation carriers without FXTAS also demonstrated significantly delayed response latencies and disrupted sensory weighting for balance control. Advancing age, male sex, increased CGG repeat size, and reduced X activation of the normal allele in premutation carrier women predicted balance dysfunction. These postural control deficits in carriers with and without FXTAS implicate dysfunctional cerebellar neural networks and may provide valuable outcome markers for tailored rehabilitative interventions. Our findings suggest that CDP may provide sensitive measures for early detection of postural control impairments in at-risk carriers and better characterize balance dysfunction and progression in FXTAS.
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12
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Schneider A, Johnston C, Tassone F, Sansone S, Hagerman RJ, Ferrer E, Rivera SM, Hessl D. Broad autism spectrum and obsessive-compulsive symptoms in adults with the fragile X premutation. Clin Neuropsychol 2016; 30:929-43. [PMID: 27355445 DOI: 10.1080/13854046.2016.1189536] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
OBJECTIVE Clinical observations and a limited number of research studies provide evidence that the fragile X premutation may confer risk for autism, executive dysfunction, and psychopathology. The link to autism spectrum symptoms and social cognition deficits with the premutation remains uncertain, and thus was the focus of the present investigation. METHOD Our sample included 131 individuals, 42 men/22 women with the FMR1 premutation (mean age = 31.83 ± 8.59 years) with a normal neurological exam, and 48 men/19 women healthy age-matched controls (mean age = 29.48 ± 7.29 years). Individuals completed a comprehensive neuropsychological battery with additional assessments for social cognition, broad autism spectrum, and obsessive-compulsive (OC) symptoms. RESULTS Premutation carriers self-reported higher rates of autism-related symptoms (Autism Quotient; p = .001). Among males only, premutation carriers showed more atypical social interaction (p < .001) and stereotyped behavior (p = .014) during standardized clinical examination on the Autism Diagnostic Observation Schedule (ADOS) relative to controls. Female premutation carriers reported significantly higher rates of OC symptoms compared to control females (p = .012). Molecular measures defining the expanded premutation (FMR1 CGG repeat length and/or mRNA) were significantly associated with a measure of theory of mind (Reading the Mind in the Eyes Task). CONCLUSIONS The results of this study indicate a higher rate of broad autism spectrum symptoms in some males with the premutation and provide evidence for an obsessive-compulsive subtype in female premutation carriers.
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Affiliation(s)
- A Schneider
- a MIND Institute, UC Davis Medical Center , Sacramento , CA , USA.,c Department of Pediatrics , UC Davis School of Medicine , Sacramento , CA , USA
| | - C Johnston
- a MIND Institute, UC Davis Medical Center , Sacramento , CA , USA.,b Department of Psychiatry and Behavioral Sciences , UC Davis School of Medicine , Sacramento , CA , USA
| | - F Tassone
- a MIND Institute, UC Davis Medical Center , Sacramento , CA , USA.,f Department of Biochemistry and Molecular Medicine , UC Davis , Davis , CA , USA
| | - S Sansone
- a MIND Institute, UC Davis Medical Center , Sacramento , CA , USA.,g Department of Human Development , UC Davis , Davis , CA , USA
| | - R J Hagerman
- a MIND Institute, UC Davis Medical Center , Sacramento , CA , USA.,c Department of Pediatrics , UC Davis School of Medicine , Sacramento , CA , USA
| | - E Ferrer
- d Department of Psychology , UC Davis , Davis , CA , USA
| | - S M Rivera
- a MIND Institute, UC Davis Medical Center , Sacramento , CA , USA.,d Department of Psychology , UC Davis , Davis , CA , USA.,e Center for Mind and Brain, UC Davis , Davis , CA , USA
| | - D Hessl
- a MIND Institute, UC Davis Medical Center , Sacramento , CA , USA.,b Department of Psychiatry and Behavioral Sciences , UC Davis School of Medicine , Sacramento , CA , USA
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Birch RC, Hocking DR, Cornish KM, Menant JC, Georgiou-Karistianis N, Godler DE, Wen W, Hackett A, Rogers C, Trollor JN. Preliminary evidence of an effect of cerebellar volume on postural sway in FMR1 premutation males. GENES BRAIN AND BEHAVIOR 2015; 14:251-9. [PMID: 25689687 DOI: 10.1111/gbb.12204] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Revised: 01/27/2015] [Accepted: 01/28/2015] [Indexed: 11/29/2022]
Abstract
Recent evidence suggests that early changes in postural control may be discernible among females with premutation expansions (55-200 CGG repeats) of the fragile X mental retardation 1 (FMR1) gene at risk of developing fragile X-associated tremor ataxia syndrome (FXTAS). Cerebellar dysfunction is well described in males and females with FXTAS, yet the interrelationships between cerebellar volume, CGG repeat length, FMR1 messenger RNA (mRNA) levels and changes in postural control remain unknown. This study examined postural sway during standing in a cohort of 22 males with the FMR1 premutation (ages 26-80) and 24 matched controls (ages 26-77). The influence of cerebellar volume, CGG repeat length and FMR1 mRNA levels on postural sway was explored using multiple linear regression. The results provide preliminary evidence that increasing CGG repeat length and decreasing cerebellar volume were associated with greater postural sway among premutation males. The relationship between CGG repeat length and postural sway was mediated by a negative association between CGG repeat size and cerebellar volume. While FMR1 mRNA levels were significantly elevated in the premutation group and correlated with CGG repeat length, FMR1 mRNA levels were not significantly associated with postural sway scores. These findings show for the first time that greater postural sway among males with the FMR1 premutation may reflect CGG repeat-mediated disruption in vulnerable cerebellar circuits implicated in postural control. However, longitudinal studies in larger samples are required to confirm whether the relationships between cerebellar volume, CGG repeat length and postural sway indicate greater risk for neurological decline.
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Affiliation(s)
- R C Birch
- Department of Developmental Disability Neuropsychiatry, School of Psychiatry, University of New South Wales, Sydney
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14
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Berman RF, Schwartzer JJ, Hunsaker MR. Mouse Models of the Fragile X Tremor/Ataxia Syndrome (FXTAS) and the Fragile X Premutation. Mov Disord 2015. [DOI: 10.1016/b978-0-12-405195-9.00039-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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15
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Seritan AL, Nguyen DV, Mu Y, Tassone F, Bourgeois JA, Schneider A, Cogswell J, Cook K, Leehey M, Grigsby J, Olichney JM, Adams P, Legg W, Zhang L, Hagerman P, Hagerman RJ. Memantine for fragile X-associated tremor/ataxia syndrome: a randomized, double-blind, placebo-controlled trial. J Clin Psychiatry 2014; 75:264-71. [PMID: 24345444 PMCID: PMC4296896 DOI: 10.4088/jcp.13m08546] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Accepted: 07/12/2013] [Indexed: 12/13/2022]
Abstract
OBJECTIVE Memantine, an uncompetitive N-methyl-d-aspartate receptor antagonist, is currently approved by the US Food and Drug Administration for the treatment of moderate to severe Alzheimer's disease. Anecdotal reports have suggested that memantine may improve neurologic and cognitive symptoms of individuals with the neurodegenerative disease fragile X-associated tremor/ataxia syndrome (FXTAS); however, its efficacy and safety in this population have not been assessed in a controlled trial. METHOD Individuals with FXTAS aged 34-80 years were enrolled in a randomized, double-blind, placebo-controlled, 1-year trial between September 2007 and August 2012. Inclusion required definite, probable, or possible FXTAS in clinical stages 1-5 according to previously published criteria. Primary outcome measures were the Behavioral Dyscontrol Scale (BDS) score and CATSYS intention tremor severity. RESULTS Ninety-four participants were randomized from 205 screened; of those, 43 and 45 started treatment with memantine (titrated to 10 mg twice daily) and placebo, respectively. Thirty-four participants receiving memantine and 36 receiving placebo completed the 1-year endpoint assessment (n = 70). Intention-to-treat analysis showed no improvement with respect to intention tremor severity (mean [SD] values with memantine vs placebo: 1.05 [0.73] vs 1.89 [2.19], P = .047) or BDS score (16.12 [5.43] vs 15.72 [3.93], P = .727) at follow-up. Post hoc analyses of participants with early FXTAS (stage ≤ 3), those with late FXTAS (stage > 3), and those in different age groups (≤ 65 years and > 65 years) also indicated no significant improvement. More frequent mild adverse events were observed in the placebo group, while more frequent moderate adverse events occurred in the memantine group (P = .007). CONCLUSION This randomized, double-blind, placebo-controlled trial of memantine for individuals with FXTAS showed no benefit compared to placebo with respect to the selected outcome measures. TRIAL REGISTRATION ClinicalTrials.gov identifier: NCT00584948.
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Affiliation(s)
- Andreea L. Seritan
- Department of Psychiatry and Behavioral Sciences, University of California Davis Medical Center, Sacramento, CA,Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA
| | - Danh V. Nguyen
- Department of Medicine, University of California Irvine, Irvine, CA,Institute for Clinical and Translational Science, University of California Irvine, Irvine, CA
| | - Yi Mu
- Department of Public Health Sciences, University of California Davis, Davis CA
| | - Flora Tassone
- Department of Biochemistry and Molecular Medicine, University of California Davis, Davis, CA
| | - James A. Bourgeois
- Department of Psychiatry, University of California San Francisco, San Francisco, CA
| | - Andrea Schneider
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA,Department of Pediatrics, University of California Davis Medical Center, Sacramento, CA
| | - Jennifer Cogswell
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA
| | - Kylee Cook
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA
| | - Maureen Leehey
- Department of Neurology, University of Colorado School of Medicine, Denver, Colorado
| | - Jim Grigsby
- Departments of Psychology and Medicine, University of Colorado Denver, Denver, Colorado
| | - John M. Olichney
- Department of Neurology, University of California Davis, Sacramento, CA,Center for Mind and Brain, University of California Davis, Davis, CA
| | - Patrick Adams
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA
| | - Wendi Legg
- Department of Neurology, University of Colorado School of Medicine, Denver, Colorado
| | - Lin Zhang
- Department of Neurology, University of California Davis, Sacramento, CA
| | - Paul Hagerman
- Department of Biochemistry and Molecular Medicine, University of California Davis, Davis, CA
| | - Randi J. Hagerman
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute, University of California Davis Medical Center, Sacramento, CA,Department of Pediatrics, University of California Davis Medical Center, Sacramento, CA
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Cognitive-motor interference during postural control indicates at-risk cerebellar profiles in females with the FMR1 premutation. Behav Brain Res 2013; 253:329-36. [PMID: 23896050 DOI: 10.1016/j.bbr.2013.07.033] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Revised: 07/16/2013] [Accepted: 07/20/2013] [Indexed: 11/22/2022]
Abstract
Recent investigations report a higher risk of motor symptoms in females with the FMR1 premutation (PM-carriers) than has hitherto been appreciated. Here we examined basic sensorimotor and postural control under different sensory and attentional dual-task demands. Physiological performance and postural sway measures from the Physiological Profile Assessment (Lord et al., 2003 [39]) were conducted in 28 female PM-carriers (mean age: 41.32±8.03) and 31 female controls with normal FMR1 alleles (mean age: 41.61±8.3). Multiple regression analyses were conducted to examine the moderating role of CGG-repeat length on the relation between age and postural sway under dual-task interference. In female PM-carriers, our results showed significantly poorer proprioceptive awareness, slower reaction time, and greater postural displacement when performing a concurrent verbal fluency task. Significantly, these findings showed age- and genetically-modulated changes in dual-task postural displacement in the medio-lateral direction in female PM-carriers. These findings highlight the sensitivity of postural control paradigms in identifying early cerebellar postural changes that may act as surrogate markers of future decline in female PM-carriers.
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17
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Neurobehavioural evidence for the involvement of the FMR1 gene in female carriers of fragile X syndrome. Neurosci Biobehav Rev 2013; 37:522-47. [DOI: 10.1016/j.neubiorev.2013.01.010] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2012] [Revised: 12/11/2012] [Accepted: 01/06/2013] [Indexed: 12/19/2022]
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Abstract
Fragile X-associated tremor/ataxia syndrome (FXTAS) is an under-recognized disorder that is a significant cause of late-adult-onset ataxia. The etiology is expansion of a trinucleotide repeat to the premutation range (55-200 CGG repeats) in the fragile X mental retardation 1 (FMR1) gene. Expansion to >200 CGGs causes fragile X syndrome, the most common heritable cause of cognitive impairment and autism. Core features of FXTAS include progressive action tremor and gait ataxia; with frequent, more variable features of cognitive decline, especially executive dysfunction, parkinsonism, neuropathy, and autonomic dysfunction. MR imaging shows generalized atrophy and frequently abnormal signal in the middle cerebellar peduncles. Autopsy reveals intranuclear inclusions in neurons and astrocytes and dystrophic white matter. FXTAS is likely due to an RNA toxic gain-of-function of the expanded-repeat mRNA. The disorder typically affects male premutation carriers over age 50, and, less often, females. Females also are at increased risk for primary ovarian insufficiency, chronic muscle pain, and thyroid disease. Treatment targets specific symptoms, but progression of disability is relentless. Although the contribution of FXTAS to the morbidity and mortality of the aging population requires further study, the disorder is likely the most common single-gene form of tremor and ataxia in the older adult population.
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Affiliation(s)
- Maureen A Leehey
- Department of Neurology, University of Colorado at Denver Health Sciences Center, Denver, CO, USA.
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19
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Allen EG, Hunter JE, Rusin M, Juncos J, Novak G, Hamilton D, Shubeck L, Charen K, Sherman SL. Neuropsychological findings from older premutation carrier males and their noncarrier siblings from families with fragile X syndrome. Neuropsychology 2011; 25:404-411. [PMID: 21443343 DOI: 10.1037/a0021879] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE Carriers of the FMR1 premutation allele are at a significantly increased risk for a late-onset neurodegenerative disorder, fragile X-associated tremor/ataxia syndrome (FXTAS). The primary features of FXTAS are late-onset intention tremor and gait ataxia. Previous reports have shown global deficits in neuropsychological measures among males with FXTAS, particularly those related to executive functioning. The purpose of this study was to investigate the neuropsychological profile among older males with the premutation who are at risk for FXTAS. METHOD Premutation carriers, 66 with motor symptoms and 23 without, and 18 noncarrier siblings were recruited from pedigrees diagnosed with fragile X syndrome, all over age 50. Subjects were examined with a neurological test battery to identify symptoms of FXTAS and a neuropsychological test battery to investigate cognitive and behavioral profiles. Linear regression and ANCOVA were used to determine the effect of the premutation on outcome measures adjusting for age and education. RESULTS We identified a significant decrease in scores of general intelligence and a marginally significant decrease in scores of logical memory among premutation carrier males with motor symptoms compared to the noncarrier male siblings. We did not identify deficits in executive functioning in our sample of premutation carrier males with motor symptoms. CONCLUSIONS Similar to other reports, we found that the FMR1 premutation is associated with deficits in general intelligence and memory among older males with symptoms of FXTAS. However, our results differed in that we found no evidence of premutation-associated executive dysfunction. We provide possible explanations for this difference.
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Affiliation(s)
| | | | - Michele Rusin
- Department of Rehabilitation Medicine, Emory University
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20
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Ataxia Rating Scales—Psychometric Profiles, Natural History and Their Application in Clinical Trials. THE CEREBELLUM 2011; 11:488-504. [DOI: 10.1007/s12311-011-0316-8] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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21
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FMR1 premutation and full mutation molecular mechanisms related to autism. J Neurodev Disord 2011; 3:211-24. [PMID: 21617890 PMCID: PMC3261276 DOI: 10.1007/s11689-011-9084-5] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2010] [Accepted: 05/09/2011] [Indexed: 11/10/2022] Open
Abstract
Fragile X syndrome (FXS) is caused by an expanded CGG repeat (>200 repeats) in the 5′ un-translated portion of the fragile X mental retardation 1 gene (FMR1) leading to a deficiency or absence of the FMR1 protein (FMRP). FMRP is an RNA-binding protein that regulates the translation of a number of other genes that are important for synaptic development and plasticity. Furthermore, many of these genes, when mutated, have been linked to autism in the general population, which may explain the high comorbidity that exists between FXS and autism spectrum disorders (ASD). Additionally, premutation repeat expansions (55 to 200 CGG repeats) may also give rise to ASD through a different molecular mechanism that involves a direct toxic effect of FMR1 mRNA. It is believed that RNA toxicity underlies much of the premutation-related involvement, including developmental concerns like autism, as well as neurodegenerative issues with aging such as the fragile X-associated tremor ataxia syndrome (FXTAS). RNA toxicity can also lead to mitochondrial dysfunction, which is common in older premutation carriers both with and without FXTAS. Many of the problems with cellular dysregulation in both premutation and full mutation neurons also parallel the cellular abnormalities that have been documented in idiopathic autism. Research regarding dysregulation of neurotransmitter systems caused by the lack of FMRP in FXS, including metabotropic glutamate receptor 1/5 (mGluR1/5) pathway and GABA pathways, has led to new targeted treatments for FXS. Preliminary evidence suggests that these new targeted treatments will also be beneficial in non-fragile X forms of autism.
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A Quantitative Assessment of Tremor and Ataxia in Female FMR1 Premutation Carriers Using CATSYS. Curr Gerontol Geriatr Res 2011; 2011:484713. [PMID: 23008705 PMCID: PMC3114433 DOI: 10.1155/2011/484713] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2010] [Accepted: 02/28/2011] [Indexed: 11/21/2022] Open
Abstract
The fragile X-associated tremor/ataxia syndrome (FXTAS) is a relatively common cause of balance problems leading to gait disturbances in older males (40%) with the premutation. FXTAS is less common in females. We utilized the CATSYS system, a quantitative measure of movement, in 23 women with FXTAS (mean age 62.7; SD 12.3), 90 women with the premutation without FXTAS (mean age 52.9; SD 9.4), and 37 controls (mean age 56.53; SD 7.8). CATSYS distinguished differences between carriers with and without FXTAS in postural tremor, postural sway, hand coordination, and reaction time tasks. Differences were also seen between carriers without FXTAS and controls in finger tapping, reaction time, and one postural sway task. However, these differences did not persist after statistical correction for multiple comparisons. Notably, there were no differences across groups in intention tremor. This is likely due to the milder symptoms in females compared to males with FXTAS.
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23
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Juncos JL, Lazarus JT, Graves-Allen E, Shubeck L, Rusin M, Novak G, Hamilton D, Rohr J, Sherman SL. New clinical findings in the fragile X-associated tremor ataxia syndrome (FXTAS). Neurogenetics 2011; 12:123-35. [PMID: 21279400 DOI: 10.1007/s10048-010-0270-5] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2010] [Accepted: 12/03/2010] [Indexed: 01/07/2023]
Abstract
The objective of this paper was to assess the phenotypic variance in patients with the Fragile X-associated Tremor Ataxia Syndrome (FXTAS) and to further elucidate genotype-phenotype correlations in the illness. A second goal was to generate hypotheses regarding symptom progression based on careful histories in our sample that can now be tested in ongoing longitudinal studies. The variability of clinical signs and symptom progression in FXTAS complicates our understanding of its phenotype and presents a series of problems in clinical trial design. Similarly, pre-motor and non-motor symptoms have not been adequately explored to answer outstanding questions regarding genotype-phenotype associations in FXTAS. This was a cross-sectional study of FMR1 premutation carriers from known fragile X syndrome pedigrees. We report on the first 50 subjects who have completed a full neurologic evaluation and a brain MRI. Subjects were selected on the basis of motor symptoms or abnormal results (>1 SD) on a quantitative instrument designed to detect mild tremor and ataxia (CATSYS 1994). A neuropsychological battery included the WAIS-III, COWA, and WCST. Statistical analysis used ANOVA and Fisher's exact test with p < 0.05. All FMR1 premutation carriers were men of mean age 65 ± 7 years. According to the diagnostic criteria of Jacquemont et al. (Am J Hum Genet 72(4):869-878, 2003), 21 subjects met criteria for definite FXTAS, 10 for probable, 9 for possible, and 10 were indeterminate. Duration of motor symptoms was significantly longer in the definitive group (8.6 ± 6) compared to the other groups (p < 0.01). The presentations in 40 subjects, excluding the indeterminate group, included: tremor 24, ataxia 5, memory symptoms 3, parkinsonism 2, and torticollis 1. The data suggest at least two dominant phenotypic presentations: (a) a tremor-dominant subtype in which the onset of ataxia is delayed; (b) a second in which ataxia is the dominant presentation from the outset. In both subtypes, once ataxia emerges it tends to track frontal cognitive changes (p < 0.01). The data support the view that FXTAS is a late-life neurodegenerative disorder with involvement of motor, non-motor, and cognitive systems. The results suggest at least two presentations with tremor- and ataxia-predominant phenotypes. In both, global cognitive decline appears to track ataxia. Prospective longitudinal studies are needed to validate this proposed evolution of FXTAS and its relevance to future clinical trials design.
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Affiliation(s)
- Jorge L Juncos
- Department of Neurology, Emory University, Atlanta, GA 30032, USA.
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25
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Tartaglia N, Borodyanskaya M, Borodyanskya M, Hall DA. Tremor in 48,XXYY syndrome. Mov Disord 2010; 24:2001-7. [PMID: 19705466 DOI: 10.1002/mds.22700] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The 48,XXYY syndrome is a form of sex chromosome aneuploidy presenting in 1:18,000 males. Tremor has been previously reported in 47,XXY and 47,XYY syndromes, but has not been well described in 48,XXYY syndrome. Ten males with 48,XXYY syndrome had a standardized neurological examination and videotaping, which included the Clinical Rating Scale for Tremor and the International Cooperative Ataxia Rating Scale. All 10 cases had postural and kinetic tremor on physical examination. Other findings included mild gait ataxia, dysarthria, and nystagmus. Three cases are reviewed. Tremor is a common finding in children and young adults with 48,XXYY syndrome. Dosage alteration of genes on the sex chromosomes may be involved in the pathogenesis of this tremor. Karyotyping should be considered in individuals presenting with tremor and a history of developmental delay, learning disabilities, tall stature, or microorchidism.
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Affiliation(s)
- Nicole Tartaglia
- Department of Pediatrics, School of Medicine, University of Colorado Denver, Child Development Unit, The Children's Hospital, 13123 East 16th Ave, B-140, Aurora, Colorado 80045, USA.
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Brouwer J, Willemsen R, Oostra B. The FMR1 gene and fragile X-associated tremor/ataxia syndrome. Am J Med Genet B Neuropsychiatr Genet 2009; 150B:782-98. [PMID: 19105204 PMCID: PMC4320942 DOI: 10.1002/ajmg.b.30910] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The CGG-repeat present in the 5'UTR of the FMR1 gene is unstable upon transmission to the next generation. The repeat is up to 55 CGGs long in the normal population. In fragile X patients, a repeat length exceeding 200 CGGs (full mutation: FM) generally leads to methylation of the repeat and the promoter region, which is accompanied by silencing of the FMR1 gene. The gene product FMRP is involved in regulation of transport and translation of certain mRNA in the dendrite, thereby affecting synaptic plasticity. This is central to learning and memory processes. The absence of FMRP seen in FM is the cause of the mental retardation seen in fragile X patients. The premutation (PM) is defined as 55-200 CGGs. Female PM carriers are at risk of developing primary ovarian insufficiency. Recently it was discovered that elderly PM carriers might develop a progressive neurodegenerative disorder called fragile X-associated tremor/ataxia syndrome. Although arising from the mutations in the same gene, distinct mechanisms lead to fragile X syndrome (absence of FMRP) and FXTAS (toxic RNA gain of function). The pathogenic mechanisms thought to underlie these disorders are discussed, with a specific emphasis on FXTAS. This review gives insight on the implications of all possible repeat length categories seen in fragile X families.
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Affiliation(s)
- J.R. Brouwer
- Department of Clinical Genetics, ErasmusMC, Rotterdam, The Netherlands
| | - R. Willemsen
- Department of Clinical Genetics, ErasmusMC, Rotterdam, The Netherlands
| | - B.A. Oostra
- Department of Clinical Genetics, ErasmusMC, Rotterdam, The Netherlands
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