一个Fabry病和α-半乳糖苷酶A基因新突变家族的长基底动脉变异和血栓形成

Fabry病是一种X连锁溶酶体蓄积病,α-半乳糖苷酶缺乏导致主要在内皮细胞和平滑肌细胞的神经酰胺三己糖苷积聚。主要累及椎-基底动脉循环的脑血管症状是Fabry病的主要致死原因之一。本文报道1个Fabry病的匈牙利家族,该病由新α-半乳糖苷酶A基因(GLA)突变所致,并且描述了该病的变异表型。这个家族中有2例男性患者确诊有长基底动脉变异,并死于血栓形成。另1例女性患者存在椎-基底动脉循环障碍,在尸检时发现高度扩张的基底动脉,但无血栓形成。另外3例家族成员的M RI显示基底动脉梗死以及扩大伸长的基底动脉。基因分析结果显示,第47位点的T…     

以反复缺血性脑卒中为突出表现的法布雷病1例报道及家系分析

目的 对一个以反复脑卒中为主要临床表现的法布雷病(Fabry病)家系进行调查,分析其临床特点和基因突变情况.方法 收集该例先证者及其家族成员的临床表现、头颅MRI检查资料.对先证者行皮肤活检,检测α-半乳糖苷酶A(α-galA)的活性.提取先证者及其弟弟、母亲的血液,进行DNA测序.结果 家系中3例患者均出现反复发作脑卒中,伴有肢端疼痛、皮肤血管角质瘤及少汗等表现.影像学均表现为基底节、脑干多发性腔隙病变.皮肤组织电镜下可见血管内皮细胞及周细胞内大量次级溶酶体结构,次级溶酶体内似有指纹结构.先证者α-galA活性明显下降,GLA基因检测发现c.672T＞G,p.N224K半合子突变(男性X染色体纯合突变).结论 Fabry家系以基底节和脑干反复脑卒中为突出临床表现,具有典型的病理学和酶学证据,GLA基因检测发现c.672T＞G,p.N224K半合子突变,该突变未见文献报道.     

Fabry病一家系临床调查及α-半乳糖苷酶A基因突变研究

【摘要】 目的 分析一个Fabry病家系先证者的临床表现,并进行该家系成员α-半乳糖苷酶A（GLA）基因突变检测。方法 回顾性分析该家系先证者临床及病理资料,采用聚合酶链式反应（PCR）直接测序法检测先证者及家系成员GLA基因编码序列。结果 ① 先证者表现为下肢皮肤色素沉着、神经性疼痛和肾脏损害,其弟死于尿毒症。肾活检提示继发性局灶节段性肾小球硬化,肾小球足细胞泡沫变性,电镜发现足细胞内大量同心圆排列的具有层状结构的包涵体,确诊Fabry病。② GLA基因测序检测发现1个无义突变,位于第2号外显子CAG119AG（Q119）,终止密码提前出现致使形成一条截短的多肽链。家系发现2例杂合子,分别为先证者母亲及侄女。结论 本研究从生化、病理及基因水平3个层面诊断了一个Fabry病家系,确诊致病原因为GLA基因点突变〔第2号外显子CAG119AG(Q119)〕,该突变在中国人群中首次报道。     

Fabry病—家系临床调查及α-半乳糖苷酶A基因突变研究

目的 分析一个Fabry病家系先证者的临床表现,并进行该家系成员α半乳糖苷酶A(GLA)基因突变检测.方法 回顾性分析该家系先证者临床及病理资料,采用聚合酶链式反应(PCR)直接测序法检测先证者及家系成员GLA基因编码序列.结果 ①先证者表现为下肢皮肤色素沉着、神经性疼痛和肾脏损害,其弟死于尿毒症.肾活检提示继发性局灶节段性肾小球硬化,肾小球足细胞泡沫变性,电镜发现足细胞内大量同心圆排列的具有层状结构的包涵体,确诊Fabry病.②GLA基因测序检测发现1个无义突变,位于第2号外显子CAG119TAG(Q119T),终止密码提前出现致使形成一条截短的多肽链.家系发现2例杂合子,分别为先证者母亲及侄女.结论 本研究从生化、病理及基因水平3个层面诊断了一个Fabry病家系,确诊致病原因为GLA基因点突变[第2号外显子CAG119 TAG(Q119T)],该突变在中国人群中首次报道.     

4岁发病的Fabry病1例

Fabry病是由于溶酶体水解酶α-半乳糖苷酶A基因缺陷导致的X连锁隐性脂质贮积病,患者体内酰基鞘鞍醇三己糖进行性贮积,导致周围神经性疼痛,心、脑、肾、眼等多脏器损害,严重者可于青壮年死亡。但由于临床表现缺乏特异性,Fabry病早期诊断困难。本文报道1例男性患儿,4岁起出现双脚脚趾间断性刀割样疼痛,近2年加重伴双手手指胀痛,11岁时来院就医。患儿病程7年,曾接受多种止痛药物治疗无效,尚未出现心、脑、肾、皮肤、眼等脏器合并症,常规生化、免疫、肌电图、神经传导速度、脑影像学检查未见异常,诊断困难。外周血白细胞α-半乳糖苷酶A活性显著降低[1.0 nmol/(h.mg protein),正常对照值24.5～86.1 nmol(h.mg protein)],符合Fabry病诊断。基因分析显示,患儿α-半乳糖苷酶A基因IVS6+2 T>C剪切突变,其母亲及妹妹未携带相同突变,证实IVS6+2 T>C为新发突变。我国Fabry病发生情况不详,患者多起病隐匿,随着疾病进展逐渐出现发作性肢体疼痛及多脏器严重损害,引起尿毒症、心肌病、卒中,残障率及死亡率很高,早期的鉴别诊断至关重要。α-半乳糖苷酶活性检测是诊断Fabry病的关键,基因突变分析有助于确诊并指导家系的遗传咨询。     

4岁发病的Fabry病1例

Fabry病是由于溶酶体水解酶α-半乳糖苷酶A基因缺陷导致的X连锁隐性脂质贮积病,患者体内酰基鞘鞍醇三己糖进行性贮积,导致周围神经性疼痛,心、脑、肾、眼等多脏器损害,严重者可于青壮年死亡。但由于临床表现缺乏特异性,Fabry病早期诊断困难。本文报道1例男性患儿,4岁起出现双脚脚趾间断性刀割样疼痛,近2年加重伴双手手指胀痛,11岁时来院就医。患儿病程7年,曾接受多种止痛药物治疗无效,尚未出现心、脑、肾、皮肤、眼等脏器合并症,常规生化、免疫、肌电图、神经传导速度、脑影像学检查未见异常,诊断困难。外周血白细胞α-半乳糖苷酶A活性显著降低［1.0 nmol/（h·mg protein）,正常对照值24.5～86.1 nmol（h·mg protein）］,符合Fabry病诊断。基因分析显示,患儿α-半乳糖苷酶A基因IVS6+2 T>C剪切突变,其母亲及妹妹未携带相同突变,证实IVS6+2 T>C为新发突变。我国Fabry病发生情况不详,患者多起病隐匿,随着疾病进展逐渐出现发作性肢体疼痛及多脏器严重损害,引起尿毒症、心肌病、卒中,残障率及死亡率很高,早期的鉴别诊断至关重要。α-半乳糖苷酶活性检测是诊断Fabry病的关键,基因突变分析有助于确诊并指导家系的遗传咨询。     

Fabry病GLA基因突变及临床表现的相关研究

目的:分析Fabry病患者的GLA基因突变类型及临床表现,探讨Fabry病基因型与临床表现型之间的关系。方法:回顾性分析一个Fabry病家系成员中所有患病者的临床资料,采用聚合酶链式反应(PCR)扩增和测序分析确定GLA基因的突变类型,并与健康对照组进行比较。结果:基因型为g.1028-1029del AA的Fabry病患者中男性患者的临床症状重于女性患者,半合子男性有典型临床表现如血管角质瘤、肢端疼痛以及心、脑、肾等损害,女性杂合子仅表现为肢端疼痛等症状;在对照组人群中也存在GLA基因突变,为1号外显子1390位点的错义突变(1390A>G),但患者无临床症状。结论:即使相同基因型的Fabry病患者其临床表现也有所不同,GLA基因突变中可能存在非致病型。     

表现为肥厚型心肌病的糖原贮积病

背景:无法解释的左室肥厚常提示诊断为肥厚型心肌病,该病是一种肌小节蛋白基因异常的疾病。由于AM P激活的蛋白激酶γ2(PRKAG2)基因的突变可引起心脏糖原积聚和左室肥厚,类似于肥厚型心肌病,所以假设其他调节糖原代谢的基因突变的患者也可被临床误诊为肥厚型心肌病。方法:对75例连续的无相互关系的肥厚型心肌病患者进行基因分析,检测出40例肌小节蛋白突变,对其余35例患者的PRKAG2、溶酶体相关膜蛋白2(LAM P2)、α半乳糖苷酶(GLA)和α-1,4-葡萄糖苷酶酸(GAA)基因进行研究。结果:没有发现基因缺陷导致的Fabry病(GLA)和Pom pe病(GA…     

Fabry病神经系统损害的研究进展

Fabry病(法布里病)是X染色体连锁隐性遗传的溶酶体贮积病,其发病机制为编码α半乳糖苷酶A的GLA基因发生突变,导致患者血浆α半乳糖苷酶A的活性部分或全部消失,从而引起神经酰胺三己糖苷为主的鞘糖脂类物质不能分解而聚集各种细胞内,造成各脏器功能受损。其中神经系统损害包括小纤维神经病及脑血管疾病等,对于不明原因的神经疼痛和早发脑卒中患者应考虑Fabry病的可能,以期早期诊治。     

心肌肥厚患者中Fabry病发病状况的临床研究

目的  研究Fabry病误诊为肥厚型心肌病的临床状况,并分析汉族人群中该病的临床特点。方法  应用底物法对427例诊断为肥厚型心肌病的患者进行α-半乳糖苷酶A活性测定,对活性异常的患者进行DNA提取基因测序分析,合并酶活性异常和基因突变的患者被认为患有此病,收集该类患者的临床资料进行分析。结果  13例患者的酶活性明显低于正常对照组（P＜0.05）。基因学分析发现,其中5例患者携带有GLA基因突变,被确诊为Fabry病。心肌肥厚的人群中,约有1.2%为Fabry病患者,该病患者的肾脏疾病发病率和肾病家族史明显高于其他左室肥厚患者(P＜0.05)。结论    Fabry病患者往往会因心肌肥厚而被误诊为肥厚型心肌病,对合并肾脏疾患的心肌肥厚患者在诊断肥厚性心肌病前,应排除Fabry病的可能性。     

PCR-SSCP技术在Anderson Fabry病诊断中的应用

目的：探讨聚合酶链反应 单链构像多态性分析对于筛选Anderson Fabry病患者的应用价值。方法:对52例肥厚型心肌病患者GLA基因的7个外显子行聚合酶链反应,其扩增产物行单链构像多态性分析。对有条带异常者的所有产物行测序分析,并测定其α 半乳糖苷酶A活性。对确诊的患者,以同样的方法筛选其家系成员。结果：1例患者的第一外显子的第1170位碱基由G突变为A。其α 半乳糖苷酶A活性明显低下,证实为该病患者。该突变使5′端非蛋白质编码区序列发生改变,通过影响mRNA的翻译过程而导致该病。结论：聚合酶链反应-单链构像多态性分析可作为Anderson Fabry病的有效筛选手段。     

肝豆状核变性基因12号外显子突变特征的研究

目的 研究中国人肝豆状核变性（ＷＤ）基因１２号外显子的突变特征,为建立直接基因诊断的方法提供理论依据。方法 应用聚合酶链反应－单链构象多态（ＰＣＲ－ＳＳＣＰ）技术,对４４例无亲缘关系的确诊患者和６０名正常对照组进行ＷＤ基因第１２号外显子的突变检测,并用ＤＮＡ测序证实其突变性质和位置。结果 ８例患者在１２号外显子检测到２种错义突变,占１８％（８／４４）,其中６例为Ｔｈｒ９３５Ｍｅｔ突变,２例为Ｇｌｙ     

脑血管狭窄患者Nf1全基因的DHPLC分析(附5例报告)

目的 探讨脑血管狭窄患者Nf1基因的突变热点及突变方式.方法 从全血中提取DNA,采用变性高效液相色谱分析(DHPLC)对5例脑血管狭窄病例进行Nf1全基因突变筛查;对DHPLC检测有差异洗脱峰型的区域进行测序分析.结果 5例无危险因素的脑血管狭窄患者Nf1全基因筛查发现:①1例出现5号外显子无义突变位点,c.541C-T;②5例均有14号和15号外显子之间内含子的基因突变;③4例有7号外显子c.702G-A的同义突变位点;④1例出现32号(c.4177G-A,Val-Ile)和46号外显子(c.6918T-G,Asn-Lys)的错义突变.结论 在目前无其他基础疾病的脑血管狭窄患者体内的Nf1基因并非以稳定野生型存在,而是具有不同类型的突变,这些突变集中在第5、7、14、32和46等外显子上.     

Mutation analysis and prenatal diagnosis of EXT1 gene mutations in Chinese patients with multiple osteochondromas

Background  Multiple osteochondromas (MO), an inherited autosomal dominant disorder, is characterized by the presence of multiple exostoses on the long bones. MO is caused by mutations in the EXT1 or EXT2 genes which encode glycosyltransferases implicated in heparin sulfate biosynthesis.

Methods  In this study, efforts were made to identify the underlying disease-causing mutations in patients from two MO families in China.

Results  Two novel EXT1 gene mutations were identified and no mutation was found in EXT2 gene. The mutation c.497T>A in exon 1 of the EXT1 gene was cosegregated with the disease phenotype in family 1 and formed a stop codon at amino acid site 166. The fetus of the proband was diagnosed negative. In family 2, the mutation c.1430-1431delCC in exon 6 of the EXT1 gene would cause frameshift and introduce a premature stop codon after the reading frame being open for 42 amino acids. The fetus of this family inherited this mutation from the father.

Conclusions  Mutation analysis of two MO families in this study demonstrates its further application in MO genetic counseling and prenatal diagnosis.

     

散发性早发帕金森病PARK2基因突变及其临床特征

目的 探讨42例散发性早发性帕金森病(EOPD)PARK2基因突变情况及突变患者的临床特点。方法 采用SYBR GreenI实时荧光定量以及DNA直接测序方法,对42例EOPD患者进行PARK2基因突变分析。结果 在42例EOPD患者中共发现5例PARK2基因突变,外显子杂合缺失突变、外显子纯合双重重复突变、复合杂合点突变各1例,另外2例存在相同的杂合小片段缺失突变。c.850G>C和c.968 973delGTGTCC为已经报道的突变,c.925G>T为未报道新突变。PARK2基因突变EOPD患者发病年龄比无PARK2基因突变者小。但是在统一帕金森病评定量表(UPDRS)3.0版第Ⅲ部分关期评分和Hoehr-Yahr关期评分上无差异。结论 散发性EOPD PARK2基因突变率为11.9%;点突变是散发性EOPD的主要突变类型;PARK2基因突变组和无突变组的EOPD患者在临床症状上和病情严重程度上无明显差异,但PARK2基因突变组发病年龄小,病程长,病情进展缓慢。     

冠心病并高同型半胱氨酸血症患者甲硫氨酸合成酶基因突变的研究

目的: 研究中国人冠心病并高同型半胱氨酸血症患者甲硫氨酸合成酶(MS)基因突变的情况.方法:应用聚合酶链反应-单链构象多态性分析(PCR-SSCP)以及DNA测序技术,检测60例患者MS基因中与结构和功能密切相关的10个外显子的点突变情况.结果:除已知的31外显子区3个SNP位点比较常见外,还发现了1个新的点突变,3 869位为A/G杂合子(A→G的错义突变可使1 195位氨基酸由异亮氨酸变为缬氨酸),此患者的血浆同型半胱氨酸血水平明显高于正常,为30.93 μmol·L-1.此外发现32内含子1个新的G/T多态性.结论:MS某种基因突变可能是影响MS酶功能及高同型半胱氨酸血症的原因之一.     

中国人腓骨肌萎缩症线粒体融合蛋白2基因突变分析

目的 分析线粒体融合蛋白2(MFN2)基因在中国人腓骨肌萎缩症的突变情况,建立快速、有效和经济的基因诊断方法 .方法 应用变性高效液相色谱(DHPLC)结合DNA直接测序的方法 ,对9个常染色体显性遗传的CMT2先证者和26个散发CMT2病例共35例患者进行MFN2基因编码区17个外显子及其侧翼区的突变检测.结果 在35例腓骨肌萎缩症患者中共检测到3种MFN2基因序列变异:c.281G→A,c.395G→A和c.408A→T,其中c.395G→A(C132T)为首次报道的致病突变,c.281G→A(R94Q)为已知致病热点突变,c.408A→T(V136V)为单核苷酸多态.DHPLC突变检测的敏感性和特异性为100%.结论 首次在国内应用DHPLC结合DNA直接测序对MFN2基因进行突变检测,发现2个致病突变和1个单核苷酸多态.DHPLC结合DNA直接测序法可准确有效地用于大规模MFN2基因突变筛查.     

Molecular basis of von Hippel-Lindau syndrome in Chinese patients

Background  Von Hippel-Lindau (VHL) syndrome is an autosomal dominant familial cancer syndrome predisposing the affected individuals to multiple tumours in various organs. The genetic basis of VHL in Southern Chinese is largely unknown. In this study, we characterized the mutation spectrum of VHL in nine unrelated Southern Chinese families.

Methods  Nine probands with clinical features of VHL, two symptomatic and eight asymptomatic family members were included in this study. Prenatal diagnosis was performed twice for one proband. Two probands had only isolated bilateral phaeochromocytoma. The VHL gene was screened for mutations by polymerase chain reaction, direct sequencing and multiplex ligation-dependent probe amplification (MLPA).

Results  The nine probands and the two symptomatic family members carried heterozygous germline mutations. Eight different VHL mutations were identified in the nine probands. One splicing mutation, NM_000551.2: c.463+1G>T, was novel. The other seven VHL mutations, c.233A>G [p.Asn78Ser], c.239G>T [p.Ser80Ile], c.319C>G [p.Arg107Gly], c.481C>T [p.Arg161X], c.482G>A [p.Arg161Gln], c.499C>T [p.Arg167Trp] and an exon 2 deletion, had been previously reported. Three asymptomatic family members were positive for the mutation and the other five tested negative. In prenatal diagnosis, the fetuses were positive for the mutation.

Conclusions  Genetic analysis could accurately confirm VHL syndrome in patients with isolated tumours such as sporadic phaeochromocytoma or epididymal papillary cystadenoma. Mutation detection in asymptomatic family members allows regular tumour surveillance and early intervention to improve their prognosis. DNA-based diagnosis can have an important impact on clinical management for VHL families. 

     

Clinical and laboratory survey of 65 Chinese patients with Leigh syndrome

Background Leigh syndrome is an inherited neurodegenerative disease that emerges in infancy and childhood and presents with a clinically heterogeneous variety of neuromuscular and non-neuromuscular disorders. It can result from the inheritance of mutations in either nuclear or mitochondrial DNA. In the current study, we performed a retrospective study in 65 patients in order to investigate the clinical and genetic characteristics of Leigh syndrome in Chinese patients. Methods Sixty-five unrelated cases （35 men and 30 women） who were hospitalized in the past 12 years were reviewed. Diagnosis was based on both the clinical presentation and the characteristic neuropathologic findings of bilateral symmetric necrotizing lesions in the basal ganglia and brain stem as detected using cranial computed tomography （CT） scan or magnetic resonance imaging （MRI）. The differential diagnosis of organic acidurias and fatty acid IS-oxidation defects were performed. Specific point mutations and deletions in mitochondrial DNA （T8993G, T8993C, T9176C, A8344G, A3243G） were screened by PCR-restriction analysis and Southern blot. The SURF1 gene was sequenced. Skeletal muscle biopsies were performed in 17 （26.2%） of the patients. The diagnosis was confirmed by autopsy in 6 （9.2%） patients. Results The patients had various forms of metabolic encephalomyopathy. Filly-nine （90.8%） of the patients had the typical neuroradiological features of Leigh syndrome, including symmetrical necrotizing lesions scattered within the basal ganglia, thalamus and brain stem. Twenty （30.8%） patients were confirmed by genetic, biochemical analysis and autopsy. Specific point mutations in mitochondrial DNA were found in 5 cases （7.7%）. Of these, the A8344G mutation was detected in 2 patients. The T8993G T8993C, and A3243G point mutations were identified in 3 other patients, respectively. SURF1 mutations associated with cytochrome c oxidase deficiency were identified in 8 （12.3%） families by DNA sequencing. A G604C mutation was identified in 6 （9.2%） patients. The genotypes of 52 patients remained unknown. Conclusions Leigh syndrome presents as a diverse array of clinical features and can result from specific mutations in nuclear or mitochondrial DNA. In this study, SURF1 mutations associated with cytochrome c oxidase deficiency were identified in 8 （12.3%） out of 65 patients with Leigh syndrome. It indicates that SURF1 mutations might be a common cause of Leigh syndrome in China. The etiology of Leigh syndrome in Chinese patients represents a persistent challenge to clinicians.