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Tremor/ataxia Syndrome (ataxia + syndrome)
Kinds of Tremor/ataxia Syndrome Selected AbstractsFragile X-associated Tremor/Ataxia Syndrome (FXTAS)DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2004Paul J. Hagerman Abstract Carriers of fragile X mental retardation 1 (FMR1) premutation alleles (55 to 200 CGG repeats) are generally spared the more serious neurodevelopmental problems associated with the full-mutation carriers (>200 repeats) of fragile X syndrome. However, some adult male premutation carriers (55,200 repeats) develop a neurological syndrome involving intention tremor, ataxia, dementia, parkinsonism, and autonomic dysfunction. In excess of one-third of male premutation carriers over 50 years of age develop the fragile X- associated tremor/ataxia syndrome (FXTAS). FXTAS also represents a new form of inclusion disease, with eosinophilic intranuclear inclusions found throughout the brain in both neurons and astrocytes. Because FXTAS appears to be relatively specific to male premutation carriers, who are known to possess elevated levels of FMR1 mRNA, the neuropathology may arise as a consequence of a toxic gain-of-function of the mRNA itself, although this proposal requires additional direct testing. One of the critical needs at present is a better estimate for the prevalence of this disorder, because FXTAS is likely to be underdiagnosed in the adult movement disorders clinics. MRDD Research Reviews 2004;10:25,30. © 2004 Wiley-Liss, Inc. [source] An Investigation of FRAXA Intermediate Allele Phenotype in A Longitudinal SampleANNALS OF HUMAN GENETICS, Issue 2 2006S. Ennis Abstract The FRAXA trinucleotide repeat at Xq27.3 gives rise to fragile X syndrome when fully expanded, and both premature ovarian failure (POF) and fragile X tremor and ataxia syndrome (FXTAS) when in the premutation range. Reports of phenotypic effects extending into the intermediate repeat range are inconsistent but some studies suggest that these smaller expansions predispose to special educational needs (SEN). This study utilises the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort to investigate cognitive and behavioural variables that might be associated with FRAXA intermediate alleles. The current study failed to find any strong evidence of association of FRAXA intermediate alleles with SEN, behavioural problems or cognitive difficulties. However, our findings illustrate some of the difficulties encountered in identifying individuals with SEN. The power to identify specific components of cognitive and behavioural difficulties was reduced due to elective drop-out, which is characteristic of longitudinal studies. Our findings demonstrate the non-random loss of participants from this cohort and highlight problems that may arise when such data are used in genetic association studies. [source] RNA-mediated neurodegeneration in repeat expansion disordersANNALS OF NEUROLOGY, Issue 3 2010Peter K. Todd MD Most neurodegenerative disorders are thought to result primarily from the accumulation of misfolded proteins, which interfere with protein homeostasis in neurons. For a subset of diseases, however, noncoding regions of RNAs assume a primary toxic gain-of-function, leading to degeneration in many tissues, including the nervous system. Here we review a series of proposed mechanisms by which noncoding repeat expansions give rise to nervous system degeneration and dysfunction. These mechanisms include transcriptional alterations and the generation of antisense transcripts, sequestration of mRNA-associated protein complexes that lead to aberrant mRNA splicing and processing, and alterations in cellular processes, including activation of abnormal signaling cascades and failure of protein quality control pathways. We place these potential mechanisms in the context of known RNA-mediated disorders, including the myotonic dystrophies and fragile X tremor ataxia syndrome, and discuss recent results suggesting that mRNA toxicity may also play a role in some presumably protein-mediated neurodegenerative disorders. Lastly, we comment on recent progress in therapeutic development for these RNA-dominant diseases. ANN NEUROL 2010;67:291,300 [source] FUS-Immunoreactive Intranuclear Inclusions in Neurodegenerative DiseaseBRAIN PATHOLOGY, Issue 3 2010John Woulfe Abstract Neuronal intranuclear inclusions (NIIs) are a histopathological hallmark of several neurodegenerative disorders. However, the role played by NIIs in neurodegenerative pathogenesis remains enigmatic. Defining their molecular composition represents an important step in understanding the pathophysiology of these disorders. Recently, a nuclear protein, "fused-in-sarcoma" (FUS) was identified as the pathological protein in two forms of frontotemporal lobar degeneration (FTLD-IF, formerly known as neuronal intermediate filament inclusion disease, and FTLD-UPS, formerly known as atypical FTLD-U), both of which are characterized by the presence of NII. The objective of the present study was to determine the range of neurodegenerative disorders characterized by FUS-positive NIIs. Immunostaining for FUS revealed intense reactivity of NIIs in FTLD-IF and FTLD-UPS as well as in Huntington's disease, spinocerebellar ataxias 1 and 3, and neuronal intranuclear inclusion body disease. In contrast, there was no FUS staining of NIIs in inherited forms of FTLD-TDP caused by GRN and VCP mutations, fragile-X-associated tremor ataxia syndrome, or oculopharyngeal muscular dystrophy. In a cell culture model of Huntington's disease, NIIs were intensely FUS-positive. NII-bearing cells displayed loss of the normal diffuse nuclear pattern of FUS staining. This suggests that sequestration of nuclear FUS by NIIs may interfere with its normal nuclear localization. [source] Clinical involvement in daughters of men with fragile X-associated tremor ataxia syndromeCLINICAL GENETICS, Issue 1 2010W Chonchaiya Chonchaiya W, Nguyen DV, Au J, Campos L, Berry-Kravis EM, Lohse K, Mu Y, Utari A, Hervey C, Wang L, Sorensen P, Cook K, Gane L, Tassone F, Hagerman RJ. Clinical involvement in daughters of men with fragile X-associated tremor ataxia syndrome. Women with the fragile X mental retardation 1 (FMR1) premutation often have concerns about neurological and medical problems, as they become older and if their fathers experience fragile X-associated tremor/ataxia syndrome (FXTAS). We therefore determined the prevalence of these problems in 110 daughters of men with FXTAS [mean age of 44.8 years (SD 8.2)]. We compared them with 43 female controls with normal FMR1 alleles [mean age of 43.8 years (SD 8.1)] and 36 premutation carrier daughters of parents with the premutation, but without FXTAS [mean age of 43.5 years (SD 7.7)]. Overall, daughters of men with FXTAS have a higher prevalence of neurological symptoms including tremor, balance problems, memory problems, and dizziness, menopausal symptoms, and psychiatric involvement including sleep problems and anxiety when compared with non-carrier female controls. Reported balance problems and menopausal symptoms were significantly higher in daughters of men with FXTAS than in carrier daughters of parents without FXTAS, suggesting the potential influence of background gene effects. Therefore, neurological, psychological and gynecological surveillance should be warranted to better provide appropriate counseling, management and care for daughters of men with FXTAS. Biological markers of additional gene effects that predispose individuals with the premutation to FXTAS need to be developed. [source] Fragile X-associated Tremor/Ataxia Syndrome (FXTAS)DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2004Paul J. Hagerman Abstract Carriers of fragile X mental retardation 1 (FMR1) premutation alleles (55 to 200 CGG repeats) are generally spared the more serious neurodevelopmental problems associated with the full-mutation carriers (>200 repeats) of fragile X syndrome. However, some adult male premutation carriers (55,200 repeats) develop a neurological syndrome involving intention tremor, ataxia, dementia, parkinsonism, and autonomic dysfunction. In excess of one-third of male premutation carriers over 50 years of age develop the fragile X- associated tremor/ataxia syndrome (FXTAS). FXTAS also represents a new form of inclusion disease, with eosinophilic intranuclear inclusions found throughout the brain in both neurons and astrocytes. Because FXTAS appears to be relatively specific to male premutation carriers, who are known to possess elevated levels of FMR1 mRNA, the neuropathology may arise as a consequence of a toxic gain-of-function of the mRNA itself, although this proposal requires additional direct testing. One of the critical needs at present is a better estimate for the prevalence of this disorder, because FXTAS is likely to be underdiagnosed in the adult movement disorders clinics. MRDD Research Reviews 2004;10:25,30. © 2004 Wiley-Liss, Inc. [source] Characterisation of FXTAS related isolated intranuclear protein inclusions using laser tweezers Raman spectroscopyJOURNAL OF RAMAN SPECTROSCOPY, Issue 1 2010Tobias J. Moritz Abstract We report the analysis of the vibrational modes of intranuclear protein inclusions isolated from the brain of human subjects with the Fragile X-associated tremor/ataxia syndrome (FXTAS). In this preliminary study, Raman spectra of optically trapped inclusions were measured and analysed to determine protein composition and structure. Our main findings are as follows: (1) The spectra of protein inclusions are characteristic of H2A and H2B histones, which correlate with previous mass spectrometry (MS) studies; (2) Tyrosine is present in its OH form and exposed at the protein surface; (3) Zn and to a lesser extent Cu bound to histidine side chains are detected in the inclusions; (4) The tryptophan side-chain torsion angle is calculated to be 102°; (5) Several potential spectroscopic markers for the inclusions of FXTAS are identified. These results show the capability of using laser tweezers Raman spectroscopy to identify protein inclusions in a non-perturbative way and to gain further insight into the pathogenesis and progression of FXTAS in human subjects and in experimental models of this disorder. Copyright © 2009 John Wiley & Sons, Ltd. [source] Screen for expanded FMR1 alleles in patients with essential tremorMOVEMENT DISORDERS, Issue 8 2004Dolores Garcia Arocena MS Abstract Fragile X-associated tremor/ataxia syndrome (FXTAS), a neurodegenerative disorder, was described recently among male carriers of expanded alleles (55,200 CGG repeats; premutation range) of the fragile X mental retardation 1 (FMR1) gene. Major features of the syndrome include intention tremor, gait ataxia, and parkinsonism in men over 50 years of age. This disorder is believed to be relatively common, possibly affecting 1 in 3,000 men over the age of 50 years in the general population. This raises the possibility that some patients presenting with essential tremor (ET) may harbor expanded FMR1 alleles. We screened 81 ET patients (40 males, 41 females) for expanded FMR1 alleles to determine whether ET is associated with such alleles. None of the ET cases had the premutation genotype. CGG repeat sizes ranged from 5 to 47 repeats within this study population, suggesting that expanded FMR1 alleles are uncommon among patients with ET. Screening of movement disorder patients with other clinical features of FXTAS (e.g., ataxia and parkinsonism) may be more likely to yield expanded FMR1 alleles. © 2004 Movement Disorder Society [source] Treatment of imbalance with varenicline (Chantix®): report of a patient with fragile X tremor/ataxia syndromeACTA NEUROLOGICA SCANDINAVICA, Issue 2 2009T. A. Zesiewicz We describe the case of a man with Fragile X tremor/ataxia syndrome, whose ataxia and imbalance improved with the use of varenicline (Chantix®) and reverted to baseline 10 days after varenicline was discontinued. Varenicline was started as part of a smoking cessation program. [source] Clinical involvement in daughters of men with fragile X-associated tremor ataxia syndromeCLINICAL GENETICS, Issue 1 2010W Chonchaiya Chonchaiya W, Nguyen DV, Au J, Campos L, Berry-Kravis EM, Lohse K, Mu Y, Utari A, Hervey C, Wang L, Sorensen P, Cook K, Gane L, Tassone F, Hagerman RJ. Clinical involvement in daughters of men with fragile X-associated tremor ataxia syndrome. Women with the fragile X mental retardation 1 (FMR1) premutation often have concerns about neurological and medical problems, as they become older and if their fathers experience fragile X-associated tremor/ataxia syndrome (FXTAS). We therefore determined the prevalence of these problems in 110 daughters of men with FXTAS [mean age of 44.8 years (SD 8.2)]. We compared them with 43 female controls with normal FMR1 alleles [mean age of 43.8 years (SD 8.1)] and 36 premutation carrier daughters of parents with the premutation, but without FXTAS [mean age of 43.5 years (SD 7.7)]. Overall, daughters of men with FXTAS have a higher prevalence of neurological symptoms including tremor, balance problems, memory problems, and dizziness, menopausal symptoms, and psychiatric involvement including sleep problems and anxiety when compared with non-carrier female controls. Reported balance problems and menopausal symptoms were significantly higher in daughters of men with FXTAS than in carrier daughters of parents without FXTAS, suggesting the potential influence of background gene effects. Therefore, neurological, psychological and gynecological surveillance should be warranted to better provide appropriate counseling, management and care for daughters of men with FXTAS. Biological markers of additional gene effects that predispose individuals with the premutation to FXTAS need to be developed. [source] |