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Teeratorn Pulkes - One of the best experts on this subject based on the ideXlab platform.
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Trinucleotide Repeat Expansion of tata binding protein gene associated with parkinson s disease a thai multicenter study
Parkinsonism & Related Disorders, 2016Co-Authors: Lulin Choubtum, Pirada Witoonpanich, Kongkiat Kulkantrakorn, Suchat Hanchaiphiboolkul, Sunsanee Pongpakdee, Somsak Tiamkao, Teeratorn PulkesAbstract:Abstract Introduction Spinocerebellar ataxia type 17 (SCA17) is an inherited cerebellar degeneration associated with Trinucleotide Repeat Expansions in the TATA-binding protein gene (TBP). Low-range Expansions of TBP have recently been described in association with Parkinson's disease (PD). However, these low-range Expansion alleles were also observed in healthy individuals. Prior distinct findings may result from reduced penetrance or age-dependent susceptibility, which may influence phenotypic expression. Methods A case-control study of 456 PD patients and 374 control subjects was conducted. Data and blood samples were collected during 2008–2013. Control subjects were individuals over 65 years old without parkinsonism. Sizes of TBP Trinucleotide Repeats were analyzed. All available carriers of the TBP Repeat of ≥40 Repeats were re-examined. Results A high prevalence of carriers of TBP Repeat Expansion ≥41 developed PD, mainly at an advanced age. Half of these carriers had onset after 70 years of age (range 34–84). Seven participants carried Expansion alleles of ≥42, and all had PD. Fourteen participants (six patients and eight controls) carried a heterozygous 41-Repeat allele. At the current mean age of 79 years and mean follow-up period of 4 years, three out of the eight control carriers of the 41-Repeat allele developed PD, while none of the thirteen asymptomatic carriers of the 40-Repeat allele did. Conclusions A high prevalence of PD was observed in carriers of low-range Expansions of TBP (41–45 Repeats), especially in elderly. This finding suggests that cut-off value for pathological TBP Repeat Expansion appear to be 41.
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Trinucleotide Repeat Expansion of TATA-binding protein gene associated with Parkinson's disease: A Thai multicenter study.
Parkinsonism & related disorders, 2016Co-Authors: Lulin Choubtum, Pirada Witoonpanich, Kongkiat Kulkantrakorn, Suchat Hanchaiphiboolkul, Sunsanee Pongpakdee, Somsak Tiamkao, Teeratorn PulkesAbstract:Spinocerebellar ataxia type 17 (SCA17) is an inherited cerebellar degeneration associated with Trinucleotide Repeat Expansions in the TATA-binding protein gene (TBP). Low-range Expansions of TBP have recently been described in association with Parkinson's disease (PD). However, these low-range Expansion alleles were also observed in healthy individuals. Prior distinct findings may result from reduced penetrance or age-dependent susceptibility, which may influence phenotypic expression. A case-control study of 456 PD patients and 374 control subjects was conducted. Data and blood samples were collected during 2008-2013. Control subjects were individuals over 65 years old without parkinsonism. Sizes of TBP Trinucleotide Repeats were analyzed. All available carriers of the TBP Repeat of ≥40 Repeats were re-examined. A high prevalence of carriers of TBP Repeat Expansion ≥41 developed PD, mainly at an advanced age. Half of these carriers had onset after 70 years of age (range 34-84). Seven participants carried Expansion alleles of ≥42, and all had PD. Fourteen participants (six patients and eight controls) carried a heterozygous 41-Repeat allele. At the current mean age of 79 years and mean follow-up period of 4 years, three out of the eight control carriers of the 41-Repeat allele developed PD, while none of the thirteen asymptomatic carriers of the 40-Repeat allele did. A high prevalence of PD was observed in carriers of low-range Expansions of TBP (41-45 Repeats), especially in elderly. This finding suggests that cut-off value for pathological TBP Repeat Expansion appear to be 41. Copyright © 2016 Elsevier Ltd. All rights reserved.
Michel Koenig - One of the best experts on this subject based on the ideXlab platform.
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Evolution of the Friedreich's Ataxia Trinucleotide Repeat Expansion: Founder Effect and Premutations
Proceedings of the National Academy of Sciences of the United States of America, 1997Co-Authors: Mireille Cossée, Michèle Schmitt, Victoria Campuzano, Laurence Reutenauer, Céline Moutou, Jean-louis Mandel, Michel KoenigAbstract:Friedreich's ataxia, the most frequent inherited ataxia, is caused, in the vast majority of cases, by large GAA Repeat Expansions in the first intron of the frataxin gene. The normal sequence corresponds to a moderately polymorphic Trinucleotide Repeat with bimodal size distribution. Small normal alleles have approximately eight to nine Repeats whereas a more heterogeneous mode of large normal alleles ranges from 16 to 34 GAA. The latter class accounts for approximately 17% of normal alleles. To identify the origin of the Expansion mutation, we analyzed linkage disequilibrium between Expansion mutations or normal alleles and a haplotype of five polymorphic markers within or close to the frataxin gene; 51% of the Expansions were associated with a single haplotype, and the other Expansions were associated with haplotypes that could be related to the major one by mutation at a polymorphic marker or by ancient recombination. Of interest, the major haplotype associated with Expansion is also the major haplotype associated with the larger alleles in the normal size range and was almost never found associated with the smaller normal alleles. The results indicate that most if not all large normal alleles derive from a single founder chromosome and that they represent a reservoir for larger Expansion events, possibly through "premutation" intermediates. Indeed, we found two such alleles (42 and 60 GAA) that underwent cataclysmic Expansion to pathological range in a single generation. This stepwise evolution to large Trinucleotide Expansions already was suggested for myotonic dystrophy and fragile X syndrome and may relate to a common mutational mechanism, despite sequence motif differences.
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evolution of the friedreich s ataxia Trinucleotide Repeat Expansion founder effect and premutations
Proceedings of the National Academy of Sciences of the United States of America, 1997Co-Authors: Mireille Cossée, Michèle Schmitt, Victoria Campuzano, Laurence Reutenauer, Céline Moutou, Jean-louis Mandel, Michel KoenigAbstract:Friedreich’s ataxia, the most frequent inherited ataxia, is caused, in the vast majority of cases, by large GAA Repeat Expansions in the first intron of the frataxin gene. The normal sequence corresponds to a moderately polymorphic Trinucleotide Repeat with bimodal size distribution. Small normal alleles have approximately eight to nine Repeats whereas a more heterogeneous mode of large normal alleles ranges from 16 to 34 GAA. The latter class accounts for ≈17% of normal alleles. To identify the origin of the Expansion mutation, we analyzed linkage disequilibrium between Expansion mutations or normal alleles and a haplotype of five polymorphic markers within or close to the frataxin gene; 51% of the Expansions were associated with a single haplotype, and the other Expansions were associated with haplotypes that could be related to the major one by mutation at a polymorphic marker or by ancient recombination. Of interest, the major haplotype associated with Expansion is also the major haplotype associated with the larger alleles in the normal size range and was almost never found associated with the smaller normal alleles. The results indicate that most if not all large normal alleles derive from a single founder chromosome and that they represent a reservoir for larger Expansion events, possibly through “premutation” intermediates. Indeed, we found two such alleles (42 and 60 GAA) that underwent cataclysmic Expansion to pathological range in a single generation. This stepwise evolution to large Trinucleotide Expansions already was suggested for myotonic dystrophy and fragile X syndrome and may relate to a common mutational mechanism, despite sequence motif differences.
Lulin Choubtum - One of the best experts on this subject based on the ideXlab platform.
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Trinucleotide Repeat Expansion of tata binding protein gene associated with parkinson s disease a thai multicenter study
Parkinsonism & Related Disorders, 2016Co-Authors: Lulin Choubtum, Pirada Witoonpanich, Kongkiat Kulkantrakorn, Suchat Hanchaiphiboolkul, Sunsanee Pongpakdee, Somsak Tiamkao, Teeratorn PulkesAbstract:Abstract Introduction Spinocerebellar ataxia type 17 (SCA17) is an inherited cerebellar degeneration associated with Trinucleotide Repeat Expansions in the TATA-binding protein gene (TBP). Low-range Expansions of TBP have recently been described in association with Parkinson's disease (PD). However, these low-range Expansion alleles were also observed in healthy individuals. Prior distinct findings may result from reduced penetrance or age-dependent susceptibility, which may influence phenotypic expression. Methods A case-control study of 456 PD patients and 374 control subjects was conducted. Data and blood samples were collected during 2008–2013. Control subjects were individuals over 65 years old without parkinsonism. Sizes of TBP Trinucleotide Repeats were analyzed. All available carriers of the TBP Repeat of ≥40 Repeats were re-examined. Results A high prevalence of carriers of TBP Repeat Expansion ≥41 developed PD, mainly at an advanced age. Half of these carriers had onset after 70 years of age (range 34–84). Seven participants carried Expansion alleles of ≥42, and all had PD. Fourteen participants (six patients and eight controls) carried a heterozygous 41-Repeat allele. At the current mean age of 79 years and mean follow-up period of 4 years, three out of the eight control carriers of the 41-Repeat allele developed PD, while none of the thirteen asymptomatic carriers of the 40-Repeat allele did. Conclusions A high prevalence of PD was observed in carriers of low-range Expansions of TBP (41–45 Repeats), especially in elderly. This finding suggests that cut-off value for pathological TBP Repeat Expansion appear to be 41.
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Trinucleotide Repeat Expansion of TATA-binding protein gene associated with Parkinson's disease: A Thai multicenter study.
Parkinsonism & related disorders, 2016Co-Authors: Lulin Choubtum, Pirada Witoonpanich, Kongkiat Kulkantrakorn, Suchat Hanchaiphiboolkul, Sunsanee Pongpakdee, Somsak Tiamkao, Teeratorn PulkesAbstract:Spinocerebellar ataxia type 17 (SCA17) is an inherited cerebellar degeneration associated with Trinucleotide Repeat Expansions in the TATA-binding protein gene (TBP). Low-range Expansions of TBP have recently been described in association with Parkinson's disease (PD). However, these low-range Expansion alleles were also observed in healthy individuals. Prior distinct findings may result from reduced penetrance or age-dependent susceptibility, which may influence phenotypic expression. A case-control study of 456 PD patients and 374 control subjects was conducted. Data and blood samples were collected during 2008-2013. Control subjects were individuals over 65 years old without parkinsonism. Sizes of TBP Trinucleotide Repeats were analyzed. All available carriers of the TBP Repeat of ≥40 Repeats were re-examined. A high prevalence of carriers of TBP Repeat Expansion ≥41 developed PD, mainly at an advanced age. Half of these carriers had onset after 70 years of age (range 34-84). Seven participants carried Expansion alleles of ≥42, and all had PD. Fourteen participants (six patients and eight controls) carried a heterozygous 41-Repeat allele. At the current mean age of 79 years and mean follow-up period of 4 years, three out of the eight control carriers of the 41-Repeat allele developed PD, while none of the thirteen asymptomatic carriers of the 40-Repeat allele did. A high prevalence of PD was observed in carriers of low-range Expansions of TBP (41-45 Repeats), especially in elderly. This finding suggests that cut-off value for pathological TBP Repeat Expansion appear to be 41. Copyright © 2016 Elsevier Ltd. All rights reserved.
Mireille Cossée - One of the best experts on this subject based on the ideXlab platform.
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Evolution of the Friedreich's Ataxia Trinucleotide Repeat Expansion: Founder Effect and Premutations
Proceedings of the National Academy of Sciences of the United States of America, 1997Co-Authors: Mireille Cossée, Michèle Schmitt, Victoria Campuzano, Laurence Reutenauer, Céline Moutou, Jean-louis Mandel, Michel KoenigAbstract:Friedreich's ataxia, the most frequent inherited ataxia, is caused, in the vast majority of cases, by large GAA Repeat Expansions in the first intron of the frataxin gene. The normal sequence corresponds to a moderately polymorphic Trinucleotide Repeat with bimodal size distribution. Small normal alleles have approximately eight to nine Repeats whereas a more heterogeneous mode of large normal alleles ranges from 16 to 34 GAA. The latter class accounts for approximately 17% of normal alleles. To identify the origin of the Expansion mutation, we analyzed linkage disequilibrium between Expansion mutations or normal alleles and a haplotype of five polymorphic markers within or close to the frataxin gene; 51% of the Expansions were associated with a single haplotype, and the other Expansions were associated with haplotypes that could be related to the major one by mutation at a polymorphic marker or by ancient recombination. Of interest, the major haplotype associated with Expansion is also the major haplotype associated with the larger alleles in the normal size range and was almost never found associated with the smaller normal alleles. The results indicate that most if not all large normal alleles derive from a single founder chromosome and that they represent a reservoir for larger Expansion events, possibly through "premutation" intermediates. Indeed, we found two such alleles (42 and 60 GAA) that underwent cataclysmic Expansion to pathological range in a single generation. This stepwise evolution to large Trinucleotide Expansions already was suggested for myotonic dystrophy and fragile X syndrome and may relate to a common mutational mechanism, despite sequence motif differences.
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evolution of the friedreich s ataxia Trinucleotide Repeat Expansion founder effect and premutations
Proceedings of the National Academy of Sciences of the United States of America, 1997Co-Authors: Mireille Cossée, Michèle Schmitt, Victoria Campuzano, Laurence Reutenauer, Céline Moutou, Jean-louis Mandel, Michel KoenigAbstract:Friedreich’s ataxia, the most frequent inherited ataxia, is caused, in the vast majority of cases, by large GAA Repeat Expansions in the first intron of the frataxin gene. The normal sequence corresponds to a moderately polymorphic Trinucleotide Repeat with bimodal size distribution. Small normal alleles have approximately eight to nine Repeats whereas a more heterogeneous mode of large normal alleles ranges from 16 to 34 GAA. The latter class accounts for ≈17% of normal alleles. To identify the origin of the Expansion mutation, we analyzed linkage disequilibrium between Expansion mutations or normal alleles and a haplotype of five polymorphic markers within or close to the frataxin gene; 51% of the Expansions were associated with a single haplotype, and the other Expansions were associated with haplotypes that could be related to the major one by mutation at a polymorphic marker or by ancient recombination. Of interest, the major haplotype associated with Expansion is also the major haplotype associated with the larger alleles in the normal size range and was almost never found associated with the smaller normal alleles. The results indicate that most if not all large normal alleles derive from a single founder chromosome and that they represent a reservoir for larger Expansion events, possibly through “premutation” intermediates. Indeed, we found two such alleles (42 and 60 GAA) that underwent cataclysmic Expansion to pathological range in a single generation. This stepwise evolution to large Trinucleotide Expansions already was suggested for myotonic dystrophy and fragile X syndrome and may relate to a common mutational mechanism, despite sequence motif differences.
Makoto Tamai - One of the best experts on this subject based on the ideXlab platform.
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Ophthalmological findings in patients with spinocerebellar ataxia type 1 are not correlated with neurological anticipation
Graefe's Archive for Clinical and Experimental Ophthalmology, 2001Co-Authors: Toshiaki Abe, Yasuto Itoyama, Koji Abe, Takehide Tsuda, Makoto TamaiAbstract:Background : Optic atrophy, attenuation of the oscillatory potentials (OPs) of the electroretinogram (ERG), and enlargement of corneal endothelial cells, have been reported in patients with spinocerebellar ataxia type 1 (SCA1). These patients have a Trinucleotide Repeat Expansion in the SCA1 gene and show neurological anticipation. The purpose of this study was to determine whether the ophthalmological findings are correlated with the neurological disorders, and whether ophthalmological anticipation is present in patients with SCA1. Methods : The visual acuity, ERGs, and corneal endothelial cell density were examined in 14 patients whose DNA analysis revealed an expanded Trinucleotide Repeat in an allele of the SCA1 gene. The results of the tests were compared with the Trinucleotide Repeat number and the duration of the neuronal disease. Results: The neurological disorders in the patients showed anticipation. The negative correlation between the Trinucleotide Repeat number and the neurological disorder was statistically significant ( P
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macular degeneration associated with aberrant Expansion of Trinucleotide Repeat of the sca7 gene in 2 japanese families
Archives of Ophthalmology, 2000Co-Authors: Toshiaki Abe, Yasuto Itoyama, T Tsuda, Madoka Yoshida, Yuko Wada, Tetsuya Kano, Makoto TamaiAbstract:Objective To evaluate the macular function of Japanese patients with a Trinucleotide Repeat Expansion in the spinocerebellar ataxia type 7 ( SCA7 ) gene. Methods Ophthalmic findings in patients whose DNA analysis revealed expanded alleles of the Trinucleotide Repeat in the SCA7 gene were evaluated. Results Trinucleotide Repeat was expanded from 40 to 48 in affected patients (control subjects, 12 Repeats). Affected patients were characterized by different degrees of visual acuity decrease (0.09-0.9), a tritan axis color vision, a coarse granular appearance of the macular region on scanning laser ophthalmoscopy, depression of multifocal electroretinograms, and macular degeneration. However, pigmentary changes were not observed in the retina. The Trinucleotide Repeat was longer and the onset of macular dysfunction was earlier in the younger generation. One patient in a family manifested decreased visual acuity 10 years preceding other neurologic signs. Conclusions and Clinical Relevance Patients with SCA7 mutations showed macular dysfunction or degeneration with Expansion of CAG Repeat in the SCA7 gene. However, the lesions were less pigmented than those previously reported. Patients also showed ophthalmologic anticipation, which has not been reported for the ocular changes in other patients who have Trinucleotide Repeat Expansion of the responsible genes.
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Corneal endothelial changes and Trinucleotide Repeat Expansion of DRPLA gene
British Journal of Ophthalmology, 1999Co-Authors: Norihiro Yamada, Makoto TamaiAbstract:Editor,—Dentatorubral and pallidoluysian atrophy (DRPLA) is an autosomal dominant disorder that manifests in a combination of chorea, myoclonus, seizure, ataxia, and dementia. It is caused by the unstable Expansion of a CAG Trinucleotide Repeat coding for glutamine in the DRPLA gene.1 Several other genes with an unstable Trinucleotide Repeat Expansion of CAG were cloned in some types of spinocerebellar degeneration (SCD). Several reports have also suggested an association between ocular changes and SCD.2 3 We report here the association of ocular changes in patients with an expanded allele of the Trinucleotide Repeat of the DRPLA gene. ### CASE REPORTS A 46 year old woman (IV-2 in Fig 1) noticed gait disturbance and truncal ataxia at age 36 years. When we visited her, her general condition was very severe, and visual acuities were not examined. Pupils, ocular media, and fundus examination showed normal findings. Corneal endothelial cell density was 762 cells/mm …
