162例散发性阿尔茨海默病朊蛋白基因突变的研究

目的:在162例散发性阿尔茨海默病(Alzheimer's disease,AD)患者中进行朊蛋白基因(PRNP)突变的筛查,探讨PRNP基因突变在临床诊断的AD中的发生情况以及可能的原因。方法:研究对象包括162例散发性AD患者和310例健康对照。对研究对象的PRNP基因的开放阅读框架进行PCR扩增,产物直接测序,异常者重复测序,并与对照组对比。结果:共发现3个不同的PRNP基因杂合突变,分别为S97N、F198V和R208C,突变率1.85%,结合患者的临床表型,以及未在310个正常人中发现突变,考虑这3例突变可能为病理性突变。结论:3例突变均为新突变,可能与痴呆的发生相关。     

7例散发性Creutzfeldt-Jakob病患者的PRNP和APOE基因突变/变异检测及其临床意义

目的探讨散发性Creutzfeldt-Jakob病(CJD)与朊蛋白(PRNP)基因、载脂蛋白E(APOE)基因突变/变异的关系。方法对临床很可能的7例CJD患者的PRNP基因的开放阅读框架及APOE基因第四外显子进行PCR扩增,产物直接测序,异常者重复测序。结果发现1例患者存在PRNP基因E200K杂合突变,6例患者为PRNP基因129基因型MM,1例患者存在APOE基因ε4等位基因。结论 PRNP基因E200K突变为CJD致病性突变,129MM基因型与散发性CJD易感性相关,APOE基因ε4等位基因可能与散发性CJD进展有关。     

家族性Creutzfeldt-Jakob病

目的确定家族性Creutzfeldt—Jakob病（CJD）的临床特点并探讨其可能的发病机制。方法对一个CJD家系进行系谱调查,并采用蛋白捕获法进行脑脊液14-3—3蛋白定量;应用PCR方法,结合DNA测序技术,检测朊蛋白（PrP）基因类型。结果（1）两代4例的发病年龄早于散发性CJD,而且有早发的趋势;（2）先证者脑脊液14-3—3蛋白为125ng／ml,高出截点13．9。倍;（3）先证者PRNP第788碱基和789碱基之间插入1个碱基A,致使PRNP第231位点发生插入突变;（4）患者弟弟及其女儿未发现有PrP基因突变。结论先证者为PRNP第231位点插入突变致家族性CJD,其临床表型与散发性CJD无明显不同,但发病年龄早于散发性CJD,同一家系患者死于同一年龄段。     

遗传性CJD一家系随访分析

目的随访一个遗传性朊蛋白病的家系,对全部家系成员进行朊蛋白基因(PRNP)突变的筛查,探讨患病者的表型和突变发生率。方法研究对象包括28例家系成员和310例健康对照。对研究对象的PRNP基因的开放阅读框架进行PCR扩增,产物直接测序,异常者重复测序,并与对照组对比。收集新发病例的影像和神经电生理资料。结果共发现15例G114V基因突变者,其中3例发病,12例为携带者。1例新发病的患者表现为进行性痴呆、肌阵挛、帕金森综合征,头颅MRI示左侧颞叶轻度萎缩,脑电图有典型的周期性放电。结论本家系为常染色体显性遗传的家族性CJD,新发病例的出现进一步明确了这一表型诊断,部分携带者不发病提示存在不完全外显。     

帕金森病PINK1基因R492X突变分析

目的 筛查中国帕金森病患者是否存在PINK1基因R492X无义突变.方法 应用聚合酶链反应(PCR)、DNA测序和限制性片段长度多态性(RFLP)等技术对1个帕金森病家系及120例散发性帕金森病患者进行PINK1基因R492X的突变分析.结果 在一个家系中检测出PINK1基因R492X无义突变:患者为突变纯合子,患者父母为杂合子;120例散发性帕金森病患者中未发现R492X突变.结论 PINK1基因R492X无义突变不大可能是中国散发性帕金森病患者的突变热点.     

12例散发性早发性痴呆朊蛋白基因变异的研究

目的研究12例散发性早发性痴呆患者[伴有锥体外系和(或)小脑、额叶症状]朊蛋白基因的变异。方法从患者外周血白细胞中提取基因组DNA,用多聚酶链式反应(PCR)进行朊蛋白基因的体外扩增,再用Sanger法对PCR产物进行测序分析,测序发现的变异用限制性片断长度多态性方法(RFLP)进行进一步确认。结果在12例患者中发现4种不同的朊蛋白基因杂合性变异:M 129V、E 219K、M 232R和五串联重复序列内的24个核苷酸缺失(de lR 2),其中M 232R可能是病理性突变,其余3种为基因多态性。结论与既往朊蛋白基因变异的研究相结合,考虑朊蛋白基因多态性在日本人群中相对常见,而且与朊蛋白基因突变有关的基因型-表现型的异质性关系为深入理解早发性痴呆的病因提供了新的启发。     

家族性低钾型周期性麻痹的基因突变与临床特征

目的筛查家族性低钾型周期性麻痹相关基因突变位点,总结该病基因型和临床表型的相关性.方法应用聚合酶链反应（PCR）和DNA测序技术,对14个家族性低钾型周期性麻痹家系中的14例先证者进行候选基因CACNA1S、SCN4A、KCNE3的筛查,阳性者再对其家系中其他患者和健康亲属进行测序分析.结果14个家系中有3个家系其先证者存在已知的低钾型周期性麻痹相关突变（1个家系发生CACNA1S基因R1239H突变,2个家系发生SCN4A基因的R672H突变）.进一步对3个突变家系中4例其他患者和34名健康亲属测序分析发现,R1239H突变为完全外显率,R672H突变为不全外显率.同时还发现2种突变在发病年龄和乙酰唑胺的疗效等方面存在差异.结论中国低钾型周期性麻痹患者存在CACNA1S基因R1239H和SCN4A基因的R672H突变,2种突变的临床表型存在差异.     

视神经脊髓炎外显子组学的初步研究

目的通过外显子组学测序筛查视神经脊髓炎(neuromyelitis optica,NMO)的基因突变位点,为进一步确定NMO的易感基因积累资料。方法收集散发性NMO患者4例,取其外周血后提取DNA,基于IlluminaHiSeq平台进行全外显子高通量测序,旨在发现患者中共有的基因突变位点。结果 4例患者中共存在33个共有突变位点,其中9个单核苷酸突变和24个小片段插入缺失突变,涉及29个基因。结论 4例NMO患者中共发现33个共有突变位点,涉及29个基因。     

家族性致死性失眠症的临床和睡眠多导图特征

目的报道1例经基因检查结果证实的家族性致死性失眠症(FFI)家系2例患者的临床表现、影像学检查、睡眠多导图(PSG)检查。方法对于来自于同一个家系的2例中老年亚急性进行性痴呆患者进行临床和神经心理检查,行腰穿、头颅MRI、脑血流灌注、脑电图、PSG以及PRNP基因等检查。结果(1)该家系2代中共有4位患者,先证者和其妹妹先后发病,发病年龄分别为62岁和60岁,主要表现为失眠、睡眠相关喉鸣和不自主运动,快速进展性痴呆以及自主神经障碍。自发病至去世病程分别为10个月和11个月;(2)基因检查显示20号染色体PRNP基因出现D178N突变,129位氨基酸为M/M型;(3)PSG示睡眠效率减低,睡眠结构异常,I期睡眠减少,II期睡眠比例减少,REM睡眠缺如,阻塞性呼吸暂停事件,最低血氧饱和度为83%;(4)头颅MRI基本正常;(5)PET脑血流灌注显像,双侧中下额叶葡萄糖代谢率降低,左侧丘脑前下部葡萄糖代谢率减低。结论 FFI表现为顽固性失眠及睡眠相关障碍、快速进展性痴呆以及自主神经障碍。PSG和PRNP基因检查有助于FFI诊断。     

散发性Creutzfeldt-Jakob病患者10例prion基因研究

目的 检测10例Creutzfeldt-Jakob病（CJD）患者prion基因（PRNP）外显子突变情况.方法 抽取患者外周静脉血,提取DNA,PCR法扩增PRNP外显子后直接测序,并用限制性内切酶Nsp Ⅰ检测PRNP 129位点密码子基因型.结果 2例肯定CJD患者中,1例PRNP检测未见异常,另1例PRNP第729碱基G被C取代（729G→C）,使编码prion第211个氨基酸的密码子GAG变成了GAC,翻译后第211个氨基酸由谷氨酸变为天冬氨酸（E211D）.8例很可能CJD患者中,2例PRNP第751碱基G被A取代（751G→A）,使编码prion第219个氨基酸的密码子GAG变成了AAG,翻译后第219个氨基酸由谷氨酸变为赖氨酸（E219K）.10例CJD患者PRNP 129位点密码子基因型都是甲硫氨酸纯合型.结论 1例肯定CJD患者的prion基因外显子存在一种新的点突变E211D,这很可能是导致遗传prion病发生的原因.2例很可能CJD患者的prion基因突变E219K,与M129V同属于基因多态性,而不是致病原因.prion基因检测有助于prion病的诊断.     

Pathologic evidence that the T188R mutation in PRNP is associated with prion disease

Human prion diseases can be caused by mutations in the prion protein gene PRNP. Prion disease with mutations at codon 188 has been reported in 6 cases, but only 1 had the T188R mutation and it was not pathologically confirmed. We report the clinical, neuropsychologic, imaging, genetic, and neuropathologic features of a patient with familial Creutzfeldt-Jakob disease, associated with a very rare PRNP mutation at T188R. The patient presented with prominent behavioral changes in addition to the more typical cognitive and motorimpairments seen in sporadic Creutzfeldt-Jakob disease. The autopsy confirmed prion disease pathology. This case supports the pathogenicity of the T188 PRNP mutation, demonstrates the variability of clinical phenotypes associated with certain mutations, and emphasizes the importance of testing for genetic prion disease in cases of apparently sporadic atypical dementia.     

A rapid and efficient method for the detection of point mutations of the human prion protein gene (PRNP) by direct sequencing

Creutzfeldt-Jakob disease (CJD) and related disorders occur in sporadic, acquired and inherited forms. In sporadic, iatrogenic and new variant CJD the polymorphic codon 129 of the prion protein gene (PRNP) plays an important role for the susceptibility to the disease and for the clinical and neuropathological manifestations. All the inherited forms of CJD and related disorders are linked to point or insert mutations of PRNP. The analysis of PRNP is therefore important for a correct classification of these disorders and for the identification of novel mutations. The aim of the present study is to describe a fast and easy to perform method for the direct sequencing of the PCR amplified PRNP open reading frame, by using M13 tailed primers which allow a direct and rapid method of sequencing. The goodness of this method is demonstrated in the analysis of three sporadic CJD patients with different genotypes at codon 129 and three inherited cases bearing different point mutations of PRNP: the Pro102Leu mutation linked to Gerstmann-Str?ussler-Scheinker-syndrome, the Val210Ile mutation and a novel mutation at codon 211 (Gln211Glu) both associated to familial CJD.     

Serum Progranulin Levels in Patients with Frontotemporal Lobar Degeneration and Alzheimer's Disease: Detection of GRN Mutations in a Spanish Cohort

Progranulin gene (GRN) mutations cause frontotemporal lobar degeneration (FTLD) with TDP43-positive inclusions, although its clinical phenotype is heterogeneous and includes patients classified as behavioral variant-FTLD (bvFTLD), progressive non-fluent aphasia (PNFA), corticobasal syndrome, Alzheimer's disease (AD), or Parkinson's disease (PD). Our main objective was to study if low serum progranulin protein (PGRN) levels may detect GRN mutations in a Spanish cohort of patients with FTLD or AD. Serum PGRN levels were measured in 112 subjects: 17 bvFTLD, 20 PNFA, 4 semantic dementia, 34 sporadic AD, 9 AD-PSEN1 mutation carriers, 10 presymptomatic-PSEN1 mutation carriers, and 18 control individuals. We detected 5 patients with PGRN levels below 94 ng/mL: two of them had a clinical diagnosis of bvFTLD, two of PNFA, and one of AD. The screening for GRN mutations detected two probable pathogenic mutations (p.C366fsX1 and a new mutation: p.V279GfsX5) in three patients and one mutation of unclear pathogenic nature (p.C139R) in one patient. The other patient showed a normal GRN sequence but carried a PRNP gene mutation. We observed no differences in serum PGRN levels between controls (mean = 145.5 ng/mL, SD = 28.5) and the other neurodegenerative diseases, except for the carriers of pathological GRN gene mutations (mean = 50.5 ng/mL, SD = 21.2). Null GRN mutation carriers also showed lower serum PGRN levels than the patient who was a carrier of p.C139R (92.3 ng/mL) and the one who was a carrier of the PRNP mutation (76.9 ng/mL). In conclusion, we detected GRN null mutations in patients with severely reduced serum PGRN levels, but not in patients with slightly reduced PGRN levels.     

致死性家族性失眠症的临床特点及脚基因突变分析

目的：探讨中国致死性家族性失眠症（FFI）患者的临床及PRNP基因突变特点。方法：对一个FFI家系进行调查并综合分析先证者的临床资料;应用PCR技术结合DNA直接测序方法对先证者进行PRNP基因的突变筛查,回顾分析中国已报道的FFI先证者的临床特点。结果：在该先证者检出朋^垆基因2号外显子上的c．532G〉A（p．D178N）突变及c．385AA（p．129MM）多态,据此可确诊为FFI。Meta分析提示中国FFI患者的临床表现均较典型,PRNP基因单体型均为D178N-129MM。结论：尽管FFI患者的临床表现较典型,但对临床上疑为FFI的患者,仍应进行艄ⅣP基因突变筛查以助确诊。     

Novel prion protein gene mutation at codon 196 (E196A) in a septuagenarian with Creutzfeldt–Jakob disease

Creutzfeldt–Jakob disease (CJD) is a rare and rapidly progressive neurodegenerative disease of the central nervous system, which may occur in inherited, acquired (variant and iatrogenic), or spontaneous (sporadic) forms. We report a 76-year-old Chinese man with CJD found to have a novel mutation in the prion protein gene (PRNP). The 14-3-3 protein was positive in the cerebrospinal fluid; diffusion-weighted MRI revealed ribbon-like high signal intensity in the bilateral cortices; and electroencephalography showed typical periodic synchronous discharge. CJD was diagnosed based on characteristic clinical manifestations. Interestingly, a point mutation of PRNP at codon 196 (E196A: GAG → GCG) was detected. In conclusion, we identified a patient with CJD with a novel PRNP mutation, which expands the spectrum of PRNP mutations in CJD.     

家族性中枢神经系统血管母细胞瘤VHL基因突变与临床预后分析

目的 探讨汉族人家族性中枢神经系统血管母细胞瘤（HB）的临床特点及家系表现和VHL基因突变的关系.方法 回顾性分析9个家族15例经手术和病理证实的HB患者进行临床分析.对长期随访的7个家族中的12例患者和15例相关家族成员抽取外周血进行VHL基因测序.对于测序阴性的患者,对其DNA进行三个外显子实时定量PCR测定.结果 本组15例HBs中,多发性肿瘤10例,共34个肿瘤.进行开颅和脊髓手术17次,共切除HB22个.基因测序发现在4种点突变.通过实时定量PCR发现2个家族外显子1大片段缺失.在未发病家族成员中检出携带者3例.随访期间发现2例复发和3例新生的HB,主要集中在移码突变和拼接错误的家族中.通过再次手术和对脑干HB进行γ刀治疗,效果较好.结论 VHL相关的HB易复发,并不断有新生HB出现.基因测序和实时定量PCR联合应用可以提高VHL基因突变的检出率.基因突变分析可有助于未发病基因突变携带者确诊,基因突变的分型有助于对患者的预后进行判断.     

Childhood onset in familial prion disease with a novel mutation in the PRNP gene

BACKGROUND: Up to 15% of cases of prion diseases are due to the autosomal dominant inheritance of coding PRNP mutations. OBJECTIVE: To describe the unique clinical and genetic findings in a family of East Indian origin with autosomal dominant inheritance of a novel PRNP mutation. DESIGN: Detailed neurological examination and sequencing analysis of the MAPT and PRNP genes. SETTING: Toronto Western Hospital, Toronto, Ontario. PATIENTS: Five available members of a family of East Indian origin with a rapidly progressive neurodegenerative disorder characterized by dementia, motor decline, and ataxia. RESULTS: We identified a novel Pro105Thr mutation in the PRNP gene in all of the 3 clinically affected family members but not in their unaffected relatives or normal controls. Although 5 of 6 affected family members had a relatively homogeneous phenotype and age at onset (range, 33-41 years), 1 of the 6 patients developed the disease at age 13 years. CONCLUSIONS: A novel mutation in the PRNP gene was identified in all of the available, clinically affected members of this family with a rapidly progressive neurodegenerative disease. To our knowledge, the propositus represents the youngest individual with inherited prion disease described to date.