湖南汉族人群遗传性脊髓小脑型共济失调患者三核苷酸突变频率分布

目的：研究湖南汉族人群中脊髓小脑性共济失调（SCAs）不同基因亚型的分布状况。方法：应用聚合酶链式反应（PCR）和变性聚丙烯胺凝胶电泳以及测序技术，检测分析了139个常染色体显性遗传SCA家系和61个散发SCA患者的SCA1，SCA2，SCA3，SCA6，SCA7，SCA17，齿状核红核苍白球路易体萎缩（DRPLA）三核苷酸重复序列突变。结果：在139个SCA家系中，11个家系（7．9％）有SCA1突变，9个家系（6．5％）有SCA2突变，71个SCA家系（51.1％）有SCA3突变，4个家系（2．9％）有SCA6突变，2个家系（1．4％）有SCA7突变。未检出SCA17，DRPLA亚型。在散发患者中发现1例SCA2患者、3例SCA3患者、1例SCA6患者。结论：SCA3为最常见类型；其次为SCA1，SCA2；SCA6，SCA7患者少见。     

脊髓小脑型共济失调的研究进展

脊髓小脑型共济失调(spinocerebellar ataxias,SCAs)是累及人类神经系统的主要遗传疾病之一,也是遗传性共济失调的主要类型,作为动态突变的遗传特征而备受关注。尽管共济失调是所有SCA的主要症状,但是对每一种特定SCA而言,其临床表现却是多种多样的:SCAs具有极强的遗传异质性和     

脊髓小脑型共济失调三核苷酸重复频率的检测

遗传性脊髓小脑型共济失调（ｓｐｉｎｏｃｅｒｅｂｅｌａｒａｔａｘｉａ，ＳＣＡ）是一组小脑、脊髓及脑干的神经元变性疾病，多为常染色体显性遗传，临床上以进行性小脑性共济失调为主要症状。国外自１９９３年起相继发现ＳＣＡ相关基因，包括ＳＣＡ１、ＳＣＡ２、ＳＣＡ...     

脊髓小脑性共济失调分子遗传学研究进展

遗传性共济失调是一类由于遗传因素造成的单基因神经系统变性疾病,不同位点的三核苷酸重复扩增导致不同的遗传亚型。现已发现20余种亚型的脊髓小脑性共济失调,多数是由于致病基因内存在CAG重复片段异常扩增,导致含有多聚谷氨酰胺链的突变蛋白在细胞核内沉积形成核内包涵体。     

河南汉族一脊髓小脑性共济失调家系基因突变检测

目的检测和分析河南汉族一脊髓小脑性共济失调(SCA)家系亚型分型。方法采用聚合酶链式反应(PCR)技术和DNA直接测序法分析该家系患病者SCA1、SCA2、SCA3、SCA6、SCA7、SCA12、SCA17共7种常见SCA亚型基因序列,并与家系中其他正常个体及50例健康个体基因序列进行比较分析。结果检测到该家系4例患者及家系中2例健康成员SCA3基因的1个等位基因三核苷酸序列CAG异常重复扩增,异常重复次数在71~81次。其余6种亚型基因检测无异常。结论该家系SCA患病表现为中国人常见的SCA3亚型,家系中2例健康成员可能为症状前患者。     

脊髓小脑性共济失调7型的分子遗传学诊断及临床分析

目的 研究分析脊髓小脑性共济失调7型(SCA7)的分子遗传学诊断、应用以及临床表现特征。方法 对临床诊断为SCA的36个家系43例病人、38例散发SCA患者、60名家系“健康个体”以及44名非家系正常对照人员,通过PCR及聚丙烯酰胺凝胶电泳等技术检测SCA7基因位点内CAG三核苷酸重复扩增次数,并利用ABI373测序仪对异常等位基因片段进行DNA测序。结果 我国南方正常人群SCA7等位基因CAG重复数为9~19。检出2个家族性、1个散发性共3例SCA7患者,测序证实其异常等位基因内CAG重复数目分别为65、65、63。结论 SCA7基因内部CAG三核苷酸重复异常扩增是该病致病原因,利用分子遗传学分析可进行基因诊断,为症状前诊断及遗传咨询提供依据。     

安徽地区脊髓小脑性共济失调患者不同基因亚型分布频率的研究

目的 研究安徽地区脊髓小脑性共济失调(SCA)患者各基因亚型的分布频率.方法 以临床诊断为SCA的15个家系39例患者和20例散发患者为研究对象,PCR扩增SCA1、SCA2、SCA3和SCA6基因的三核苷酸重复(TNR)片段并行变性聚丙烯酰胺凝胶电泳估算TNR片段的重复次数,对异常者行DNA克隆测序证实.结果 SCA...     

脊髓小脑性共济失调12型的分子遗传学诊断及临床分析

[目的]研究分析脊髓小脑性共济失调12型(SCA12)的分子诊断及临床表现特征。[方法]对临床诊断为脊髓小脑性共济失调(SCA)的36个家系43例患者、38例散发患者、60名家系“健康”个体及44名正常对照，通过聚合酶链反应(PCR)对SCA12基因含有CAG三核苷酸重复片段进行扩增，并利用ABI373测序仪对异常等位基因片段进行DNA测序，聚丙烯酰胺凝胶电泳并以图像分析软件计算其长度，推算所有正常和异常扩增等位基因内CAG重复次数。[结果]正常我国南方汉族人群SCA12等位基因CAG重复数目为22～27。检出1个家系患者1例，症状前患者2例，两个等位基因中一个异常等位基因内CAG重复数目为68次。[结论]SCA12比较罕见，CAG三核苷酸重复异常扩增是其致病原因，分子遗传学分析可确证临床诊断和症状前诊断，并可为遗传咨询提供依据。该例为国内首次报道。     

脊髓小脑共济失调基因分型及临床特点分析

目的分析脊髓小脑共济失调患者的基因分型及其临床特点。方法应用聚合酶链反应(PCR)对12例不明原因共济失调患者SCA1、SCA2、SCA3、SAC6、SCA7基因内CAG三核苷酸重复片段进行扩增,PCR产物经2%琼脂糖凝胶电泳检测,从而对临床确诊患者进行基因分型。结果 12例患者经基因检测7例确诊为脊髓小脑共济失调,其中SCA3型4例,SCA1型3例。各型之间临床表现相互重叠,主要表现为行走不稳、言语不清。结论 SCA3型是脊髓小脑共济失调最常见亚型,其次为SCA1型。基因检测可对临床疑诊患者进行确诊及分型。     

脊髓小脑性共济失调12型的分子遗传学诊断及临床分析

[目的]研究分析脊髓小脑性共济失调12型(SCA12)的分子诊断及临床表现特征.[方法]对临床诊断为脊髓小脑性共济失调(SCA)的36个家系43例患者、38例散发患者、60名家系"健康"个体及44名正常对照,通过聚合酶链反应(PCR)对SCA12基因含有CAG三核苷酸重复片段进行扩增,并利用ABI 373测序仪对异常等位基因片段进行DNA测序,聚丙烯酰胺凝胶电泳并以图像分析软件计算其长度,推算所有正常和异常扩增等位基因内CAG重复次数.[结果]正常我国南方汉族人群SCA12等位基因CAG重复数目为22～27.检出1个家系患者1例,症状前患者2例,两个等位基因中一个异常等位基因内CAG重复数目为68次.[结论]SCA12比较罕见,CAG三核苷酸重复异常扩增是其致病原因,分子遗传学分析可确证临床诊断和症状前诊断,并可为遗传咨询提供依据.该例为国内首次报道.     

Clinical and genetic study of spinocerebellar ataxia type 7 in East Asian population

Background Spinocerebellar ataxia type 7 （SCA7） is known as an autosomal dominant cerebellar ataxia; patients with genetically confirmed diagnoses of SCA7 have increased rapidly in recent years.However, SCA7 is a rare subtype of SCA, and most data available about SCA7 are those of white people.The aim of the present study was to systematically review the prevalence and clinical and genetic aspects of SCA7 patients in East Asian population.Methods A search for publications on SCA7 was performed by using the ＂PubMed＂ database with the published language limited in English.Publications mainly focusing on the prevalence of SCA7 in patients with SCA and the clinical and genetic features of SCA7 patients were fully reviewed and analyzed.Results The prevalence of SCA7 in SCA patients ranged from 0 to 7.7%, which was similar to those reported previously.The clinical manifestations were typically present at the 30＇s of its victims （median, 29 years; interquartile range （IQR）,19.5-36.5 years）, and the symptoms appeared 15 years （（15.17±4.22） years） earlier on average in the offspring than in the parents.Gait ataxia and visual impairment were both found in all patients of whom the clinical features were described.Mutant SCA7 alleles contained 40-100 CAG repeats, with a median of 47 repeats （IQR, 44.5-50.0）; and the offspring had 13 more repeats on average compared with their parents （12.62±19.03）.A strong negative correlation was found between CAG repeat size and the onset age of patients （r=-0.739, P=0.000）.In addition, no significant difference was found in CAG repeat sizes between patients with visual impairment as the initial symptom and those with gait disturbance as their initial symptom （P=0.476）.Conclusions The prevalence of SCA7 in SCA patients, the age at onset and CAG repeats of SCA7 patients in East Asia are consistent with those of white people.However, larger population study is needed to assess the correlation between the CAG repeat size and initial symptoms of SCA7 patients in East Asia.     

中国人遗传性脊髓小脑型共济失调患者三核苷酸突变频率的分布

目的评价ＳＣＡ１、ＳＣＡ２、ＭＪＤ／ＳＣＡ３ＣＡＧ三核苷酸扩增突变（ＣＡＧ）ｎ在中国人遗传性脊髓小脑型共济失调（ＳＣＡ）患者的分布频率。方法应用聚合酶链式反应（ＰＣＲ）和变性聚丙烯胺凝胶电泳技术，检测分析了５０名中国人常染色体显性遗传ＳＣＡ家系（其中患者７９例）的ＳＣＡ１、ＳＣＡ２、ＭＪＤ／ＳＣＡ３（ＣＡＧ）ｎ。结果在５０个ＳＣＡ家系中，１个ＳＣＡ家系有ＳＣＡ１（ＣＡＧ）ｎ突变，３个ＳＣＡ家系有ＳＣＡ２（ＣＡＧ）ｎ突变，２４个ＳＣＡ家系有ＭＪＤ／ＳＣＡ３（ＣＡＧ）ｎ突变，阳性率分别为２．０％、６．０％、４８．０％。２例ＳＣＡ１患者ＣＡＧ三核苷酸重复数为５３和６２次，而正常人为１２～３６次。７例ＳＣＡ２患者ＣＡＧ三核苷酸重复数４３～４７次，而正常人为２２～３０次。４２例ＭＪＤ／ＳＣＡ３患者ＣＡＧ三核苷酸重复数６３～７８次，而正常人为１５～３８次。另有２２个ＳＣＡ家系２８例患者，ＳＣＡ１、ＳＣＡ２、ＭＪＤ／ＳＣＡ３（ＣＡＧ）ｎ突变检测在正常范围内。结论中国ＳＣＡ主要为ＭＪＤ／ＳＣＡ３型，属于非葡萄牙型ＭＪＤ；而ＳＣＡ１型、ＳＣＡ２型少见。     

Frequency analysis of autosomal dominant spinocerebellar ataxias in mainland Chinese patients and clinical and molecular characterization of spinocerebellar ataxia type 6

Background Dominantly inherited spinocerebeUar ataxia (SCA) is a clinically and genetically heterogeneous group of neurodegenerative disorders. This study was to further assess the frequency of SCA1 (spinocerebellar ataxia type 1 ), SCA2, SCA3/MJD (spinocerebellar ataxia type 3/Machado-Joseph disease), SCA6, SCA7, SCA8, SCA10, SCA12, SCA14, SCA17 and DRPLA (dentatorubro-pallidoluysian atrophy) in mainland Chinese, and to specifically characterize mainland Chinese patients with SCA6 in terms of clinical and molecular features.Methods Using a molecular approach, we investigated SCA in 120 mainland Chinese families with dominantly inherited ataxias and in 60 mainland Chinese patients with sporadic ataxias. Clinical and molecular features of SCA6 were further characterized in 13 patients from 4 families. Results SCA3/MJD was the most common type of autosomal dominant SCA in mainland Chinese, accounting for 83 patients from 59 families (49.2%), followed by SCA2 [8(6.7%)], SCA1 [7(5.8%)], SCA6 [4(3.3%)], SCA7[1(0.8%)], SCA8(0%), SCA10(0%), SCA12(0%), SCA14(0%), SCA17(0%) and DRPLA(0%). The genes responsible for 41 (34.2%) of dominantly inherited SCA families remain to be determined. Among the 60 patients with sporadic ataxias in the present series, 3 (5.0%) was found to harbor SCA3 mutations while none was found to harbor SCA6 mutations. In the 4 families with SCA6, significant anticipation was found in the absence of genetic instability on transmission. Conclusion A geographic cluster of families with SCA6 subtype was initially identified in a mainland Chinese population.     

云南地区汉族脊髓小脑共济失调3型SCA3/MJD患者的临床特点及遗传学研究

目的通过对云南地区临床诊断为脊髓小脑共济失调的家系进行SCA3基因检测,探讨汉族人群遗传性脊髓小脑共济失调3型(spinocerebellar ataxia type 3,SCA3)患者临床特点与遗传学特征。方法对4个家系26例脊髓小脑共济失调患者进行神经系统检查和家系谱调查,应用聚合酶链反应(PCR)、琼脂糖凝胶电泳和基因测序等技术进行SCA3基因内CAG三核苷酸重复序列,并对异常等位基因片段进行DNA测序。结果临床表现以共济失调和构音障碍为主,其次表现为锥体束征、眼部症状等,认知功能障碍较少见。检出4个家系(26例患者)为SCA3,符合常染色体显性遗传特点,测序证实其异常等位基因CAG重复数目在67～82次之间。结论云南地区汉族的SCAs患者以SCA3型为主,主要表现为共济失调和构音障碍,基因检测仍是其诊断的金标准。     

8例脊髓小脑共济失调2型、3型患者的临床表型及MRI表现分析

目的:探讨脊髓小脑共济失调(SCAs)2型与3型患者的临床特征及磁共振成像(MRI)表现对此类疾病的诊断及评估价值.方法:运用分子生物学的技术方法对4个SCAs家系的8例患者进行基因检测,证实分别为SCA2型和SCA3型,回顾分析3例SCA2型患者、5例SCA3型患者的临床特点及MRI表现.结果:SCA2型患者以小脑共济失调伴锥体外系损害为主,小脑、脑干萎缩明显,伴大脑皮层萎缩;SCA3型患者以小脑共济失调伴锥体束损害为主,小脑萎缩相对较轻.结论:SCA2型与SCA3型存在遗传异质性,神经系统检查和MRI表现有助于诊断、鉴别及预后评估,基因检测是唯一的确诊方法.     

伴认知功能障碍及痉挛性疼痛脊髓小脑性共济失调3型一家系研究

目的：对伴痉挛性疼痛脊髓小脑性共济失调3型( SCA3)一家系进行临床表现及基因检测分析,探讨其临床和遗传特征,及其痉挛性疼痛的治疗方法。方法通过对SCA一家系先证者临床表现、基因检测确定SCA3亚型;检测家系成员有关SCA3基因;分析该家系中患者的临床表现、遗传特征;对伴肌肉痉挛的患者给予加巴喷丁胶囊治疗并观察疗效。结果该家系5代人中,在世的4位患者,其共同表现为小脑性共济失调、口齿不清、腱反射亢进、眼睑退缩,其中2人伴有不同程度肌肉痉挛性疼痛。先证者具有认知功能障碍。先证者及其无症状女儿和另一患者检测SCA3相关基因的CAG重复数分别为72、76、78次。2例伴肌肉痉挛疼痛的患者,接受加巴喷丁胶囊治疗,症状缓解明显。结论 SCA3具有临床表现和遗传异质性,同时加巴喷丁胶囊对缓解SCA3伴发的肌肉痉挛可能有效。     

三峡库区遗传性脊髓小脑型共济失调家系基因突变的研究

目的研究三峡库区重庆市首例诊断遗传性脊髓小脑型共济失调3型(SCA3)的基因突变和临床特征。方法运用聚合酶链反应、琼脂糖凝胶电泳等技术对一个表现为共济失调的家系(14名成员,包括6名患者)的Atxn3基因进行检测。结果检测出该家系内6名患者和3名症状前患者为SCA3型基因突变。结论三峡库区该例SCA3型家系患者存在SCA3型基因突变,与临床诊断结果一致。     

脊髓小脑共济失调1型中等重复动态突变患者临床表型分析

目的：探讨脊髓小脑共济失调1型（SCA1）中等重复动态突变患者临床表型特征。方法：采用基于CEQ8000核酸分析仪的片段分析方法对2个表型为常染色体显性遗传脊髓小脑共济失调家系进行SCA1基因CAG重复序列突变检测，并分析其临床特征。结果：所研究家系的先证者为SCA1基因CAG中等重复序列等位基因携带者，其临床表型存在共性和一定的差异。结论：本研究证实了SCA1基因CAG中等重复序列的致病性，且在不同的家系患者存在临床变异。