重庆地区脊髓小脑共济失调的临床特征分析与分子遗传学研究

目的 研究重庆地区遗传性脊髓小脑共济失调(spinocerebellar ataxia,SCA)的遗传学分型及临床表现.方法 应用聚合酶链式反应(polymerase chain reaction,PCR)和琼脂糖凝胶电泳以及DNA测序技术,分析了10个常染色体显性脊髓小脑共济失调家系及9例散发小脑性共济失调患者的SCA1、SCA2、SCA3、SCA6、SCA7、SCA12、SCA17、齿状核红核苍白球路易体萎缩(dentatorubralpallidoluysian atrophy,DRPLA)的致病基因,并结合临床资料进行分析.结果 其中8个家系分子遗传学检测明确为SCA3型,另外2个家系及散发患者均未明确其遗传学亚型.8个SCA3家系中,通过基因诊断确诊患者15例,CAG重复58 ～71次,症状前患者7例,CAG重复56 ～71次.SCA3临床表现以小脑共济失调及构音障碍为主,有典型的遗传早现现象,影像学表现为幕下脑萎缩.结论 SCA3是重庆地区最常见的脊髓小脑共济失调类型,主要表现为小脑共济失调、构音障碍及幕下脑萎缩.家族性SCA患者脑萎缩程度较散发患者轻,患者脑干萎缩程度与病程相关,病程越长,脑干萎缩越严重.     

脊髓小脑性共济失调一家系的遗传学研究

目的对一个常染色体显性遗传的脊髓小脑共济失调家系(spinocerebellar ataxias,SCA)进行基因诊断并探讨其临床特点。方法完成家系调查和系谱分析,通过聚合酶链式反应和直接测序的方法对收集到的家系成员进行脊髓小脑性共济失调致病基因CAG三核苷酸重复数目的检测。结果该家系呈常染色体显性遗传模式,家系中3名患者均于30岁后逐渐表现为行走不稳、饮水呛咳、言语不清等共济失调的临床特征。对所有家系成员进行基因诊断,结果发现,SCA2和SCA3致病基因的CAG重复数目均在正常范围内;而家系中3名患者SCA1致病基因出现异常等位基因,CAG扩增次数分别为43、48和51次,另有2名成员GAG重复次数分别为53次和50次,诊断为症状前患者。结论该家系为三核苷酸重复序列(CAG)动态突变引起的常染色体显性遗传脊髓小脑共济失调Ⅰ型,基因诊断还发现家系中2名症状前患者。     

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.     

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...     

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。     

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AB1373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。     

遗传性共济失调的临床特点与基因诊断策略

目的研究分析遗传性共济失调的临床特点及基因诊断。方法对临床诊断为遗传性共济失调(hereditary ataxia,HA)的41个家系49例患者、42例散发患者的临床特点进行分析,同时对其和66名家系健康个体,以及44名正常对照进行基因检测,以区分不同亚型。结果在HA患者中以常染色体显性遗传的小脑性共济失调最常见,突出特点是共济失调步态、锥体束征阳性。基因检测显示脊髓小脑性共济失调3型(spinocer-ebellar ataxia 3,SCA3)比例最高,其余分别为SCA2、SCA、SCA7、SCA6、SCA12。结论遗传性共济失调临床特点明显,但各亚型之间交叉重叠,基因检测可为临床提供准确的分型。     

脊髓小脑性共济失调Ⅲ型基因诊断的研究及伦理学分析

目的：根据临床患者家系病例进一步探索脊髓小脑性共济失调Ⅲ型（SCA3）的基因诊断和症状前诊断的可行性和可靠性,及其所带来的医学伦理问题。方法：采用聚合酶链反应（PCR）对SCA3患者及其血亲家属15例、30例无血缘关系正常人的SCA3基因扩增,测定基因序列、计算三核苷酸重复（TNR）拷贝数。结果：2例患者和6例无症状＂健康人＂SCA3等位基因CAG拷贝重复数异常,可分别诊断为患者和症状前患者。结论：采用基因诊断是SCA3患者、症状前患者分型和确诊的重要依据,同时要严格按照医学伦理规范进行严谨而周全的遗传测试。     

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。     

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。     

橄榄桥脑小脑萎缩的临床和磁共振的诊断价值

目的分析橄榄桥脑小脑萎缩（OPCA）的MRI表现。方法回顾分析21例临床拟诊OPCA并经MRI证实的病例,所有病例均采用1.5TMRI进行检查,使用自旋回波序列T1WI矢状位和T1WI、T2WI、FLAIR序列轴位。结果 OPCA临床表现多种多样,以小脑症状、植物神经症状及椎体外系症状多见。MRI表现主要为小脑半球、桥脑腹侧、小脑中脚和橄榄的萎缩,大脑皮质轻度萎缩。结论成年人出现小脑共济失调、植物神经功能紊乱和椎体外系症状,应早期进行MRI检查,以除外OPCA。     

橄榄体桥小脑萎缩(附一例报告)

报告1例橄揽体桥小脑萎缩患者。临床表现为进行性共济失调、言语障碍、眼球协同运动障碍及智能减退。经CT检查证实大脑皮质及小脑萎缩。结合文献复习对橄榄桥小脑萎缩的临床特点,病理特征进行了讨论。     

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.     

晚发型甲基丙二酸尿症的临床和实验室研究

目的总结晚发型甲基丙二酸尿症(MMA)的临床特点.方法对11例晚发型MMA患儿的临床表现、实验室检查结果、影像学及治疗情况进行分析.结果 11例发病年龄3岁5个月～14岁, 表现发作性呕吐、嗜睡者5例;惊厥8例;智力损害9例;运动障碍10例,其中6例双下肢无力,2例四肢无力,1例走路姿势异常,1例小脑共济失调;伴构音不清、肢体震颤各2例,遗尿3例, 贫血、肝脏大各2例.实验室检查:5例外周血红细胞平均体积(MCV)增大,3例血尿、蛋白尿, 4例肝功能异常,6例血乳酸升高.11例患儿气相色谱-质谱联用分析(GC-MS)结果显示尿甲基丙二酸水平均明显升高,其中3例伴血浆同型半胱氨酸浓度升高.10例EEG检查,8例异常.头颅MRI检查,8例异常,其中6例有脑萎缩.9例治疗初期进行了大剂量维生素B12(VB12)试验性治疗,证实均为VB12反应型.结论晚发型甲基丙二酸尿症可表现为多系统损害,但以神经系统损害为主,主要症状为运动障碍、智力低下、惊厥;确诊依靠GC-MS尿有机酸分析;多数患儿为VB12反应型.     

Clinical features of hereditary spastic paraplegia with thin corpus callosum： report of 5 Chinese cases

Hereditary spastic paraplegia is a clinically and genetically heterogeneous group of neurodegenerative disorders of the motor system, characterized by slowly progressive spasticity and weakness of the lower extremities. This study was conducted to investigate the clinical features of hereditary spastic paraplegia with thin corpus callosum (HSP-TCC). Methods Clinical data from five patients and thirty-five previously published case reports of HSP-TCC were analyzed retrospectively. Results Most patients were adolescents at the onset of the disease, presenting with spastic paraparesis of the lower limbs and mental impairment. Some patients also had other clinical features, including spasticity of the upper limbs, cerebellar ataxia, and sensory disturbances. Cranial MRIs of the five patients revealed an extremely thin corpus callosum, sometimes with widened cerebral sulci and ventricles, as well as with cerebellar and cerebral atrophy. Conclusion The main clinical features of HSP-TCC include slowly progressive spastic paraplegia, mental impairment during the second decade of life, and an extremely thin corpus callosum as shown on cranial MRIs.     

SCA3/MJD与SPG4的弥散加权成像对比研究

目的：探讨弥散加权成像(diffusion weighted imaging,DWI) 在遗传性脊髓小脑型共济失调3 型/ 马 查多- 约瑟夫病(hereditary spinocerebellar ataxia 3 and the Machado Joseph disease,SCA3/MJD) 及遗传性痉挛性 截瘫4 型(hereditary spastic paraplegia 4,SPG4) 的诊断及鉴别诊断中的价值。方法：对13 例SPG4 患者,30 例 SCA3/MJD 及27 名年龄匹配的健康志愿者进行DWI 检查,经数据后处理获得了表观扩散系数(apparent diffusion coefficient,ADC) 值。将以上数据分组进行对比研究。结果：SCA3/MJD 起病患者的ADC 值在中央前回、内囊 后肢、大脑脚、桥脑、小脑皮层及小脑白质区域较正常对照组升高。SCA3/MJD 未起病患者的ADC 值仅在小脑 齿状核位置较正常对照组增高。SCA3/MJD 起病患者仅在小脑皮层较SCA3/MJD 未起病患者ADC 值明显升高; SCA3/MJD 起病患者的ADC 值在内囊后肢、小脑皮层、小脑白质及桥脑较SPG4 患者明显增高。在中央前回, SPG4 患者的ADC 值较正常对照组明显增高。结论：DWI 对于SCA3/MJD 与SPG4 的鉴别诊断有一定的应用前景。     

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.