中国家族性肌萎缩侧索硬化患者超氧化物歧化酶1基因突变分析

目的 肌萎缩侧索硬化(ALS)是上、下运动神经元退变引起的一种进行性致死性疾病,家族性ALS占10%～20%,铜锌SOD1基因突变存在于20%的家族性患者和少数散发性患者,某些突变还具有地域分布和特殊临床表型的规律性.我们旨在分析我国3个家族性ALS家系SOD1基因突变特点,并与不同国家和地区SOD1突变比较,分析其临床表型的特征性.方法 提取患者外周血基因组DNA,采用SOD1基因的5对引物对其5个外显子进行PCR扩增,产物直接测序.归纳整理患者临床表型资料,进行表型-基因型关联分析.结果 家系1中SOD1基因外显子2的H46R杂合突变,即CAT→CGT,使得46位由编码组氨酸变为编码精氨酸.先证者48岁,女性,43岁起病,主要表现为肢体无力和萎缩.家系中其他3例患者首发症状与先证者相似,病情进展均较缓慢,生存期较长.家系2中先证者20岁,男性,临床表现为延髓性麻痹,病程进展快速,生存期1年,位于3号外显子的杂合突变,即G72C突变.其父亲也出现同样的突变,但无ALS临床表现,其姑姑也有类似病史.家系3中5例患者5号外显子的E133V杂合突变,先证者中年起病,病程逐渐进展,生存期5年.结论 H46R的杂合突变国内未见报道,国外日本人曾多次报道及巴基斯坦有1个家系报道,欧美均未见报道,推测此突变可能为亚裔所特有.G72C突变的家系,临床表型为较早发病,病程进展迅速,生存期1年,突变外显率低导致家族成员不发病,常被诊断为散发病例,因此对于散发性患者及其家族成员同时检测SOD1基因突变十分必要.E133V突变的家系为国际首先报道.     

家族性ALS的临床特征及基因分析

目的探讨肌萎缩侧索硬化症(ALS)家系的临床特点及SOD1基因突变规律。方法详细分析一个FALS大家系的临床特征、肌电图改变、遗传方式,用PCR-SSCP法检测SOD1基因的突变。结果该家系有6代、237人,其中13人患病,8人死于ALS,具典型ALS症状,但起病前有较长一段时间肌肉纤颤期。PCR-SSCP法检测SOD1基因未发现突变,为非SOD1基因突变的ALS家系。结论(1)对于家族性肌跳的患者,宜动态观察其肌电图的改变,注重临床随访;(2)该家系可能存在一个非SOD1基因的、新的FALS致病基因。     

PLA2G6基因突变致青年帕金森病的临床特征(附1例报告)

目的本文报道了一个可能致病的PLA2G6基因突变的新位点,并对PLA2G6基因突变所致青年帕金森病患者的临床特征进行探讨。方法回顾性分析1例PLA2G6基因突变相关帕金森病患者的临床资料并做相关文献复习。结果患者青年女性,隐匿性起病,病程两年余。主要临床表现为右下肢震颤、右侧肢体肌张力障碍及运动迟缓,病情逐渐进展。应用小剂量左旋多巴效果好,但维持时间较短。基因检测发现PLA2G6基因复合杂合突变:c.991GT(p.D331Y)、c.1630AG(p.M544V),后者可能是一个新的突变位点。结论 PLA2G6突变所致帕金森病临床罕见,临床表现多样,临床容易误诊,基因检查为鉴别要点。     

中国家族性肌萎缩侧索硬化患者超氧化物歧化酶1基因突变与临床表型

目的 通过对43个中国家族性肌萎缩侧索硬化(FALS)家系先证者进行铜、锌超氧化物歧化酶(SOD)1基因突变检测,分析其与临床表型的关系,探讨中国FAIS患者SOD1基因的突变分布谱及其与临床表型之间的关联性.方法 采集2008-2011年确诊的43个FALS家系的临床资料.利用PCR技术和直接测序方法,检测先证者SOD1基因突变,进一步与临床表型做关联分析.结果 43个FALS家系均呈常染色体显性遗传,先证者男女比例为1∶0.6,起病年龄(48.1±11.8)岁,上肢起病23例,占53.5％,下肢起病18例,占41.9％,延髓部起病2例,占4.6％.在10例先证者中共发现9种SOD1突变类型,其中2种为未报道的新突变.9种突变类型中8种为错义突变,1种为缺失突变.SOD1基因突变总检出率为23.3％.结论 中国FALS患者SOD1基因突变类型由原来的11种增加到19种.具有SOD1突变的FALS患者以下运动神经元损害为主.大多数SOD1突变的临床表型在不同的家系甚至同一家系中变异均较大.     

以急性延髓麻痹为首发症状的肌萎缩侧索硬化症1例报告

<正>肌萎缩侧索硬化(amyotrophic lateral sclerosis,ALS)是一种慢性进行性神经系统变性疾病,临床上多数患者以一侧或双侧手指力弱、手部小肌肉萎缩为首发症状,延髓麻痹一般发生在疾病晚期,极少数病例可作为首发症状出现。通常起病隐匿,缓慢进展,偶见亚急性进展者。急性延髓麻痹为首发症状的ALS罕见,本文报道1例以急性延髓麻痹起病的ALS病例。     

遗传性痉挛性截瘫一家系(SPG4)的临床与遗传学特点

目的 探讨遗传性痉挛性截瘫(HSP)4型患者的临床特点和基因突变. 方法观察HSP4型患者1个家系4例患者的临床特点,抽取家系5个成员的外周血,选择与已知HSP致病基因位点在物理距离上紧密连锁的微卫星分子STR进行标记.连锁分析并构建其单体型后进行突变筛选.结果 基因分型结果显示了D2S2351与D2S2255与致病基因不排除连锁.其他位点LOD值为负值排除连锁,因此初步定位于HSP致病基因(SPG)4,所对应的候选基因是spastin基因.突变筛查发现患者spastin基因第8外显子1168位置碱基A/G杂合突变.结论该HSP家系患者具有典型临床表现,为spastin基因第8外显子1168核苷酸的位置上A/G杂合突变所致.     

中国华东地区家族性肌萎缩侧索硬化症患者SOD1基因突变检测及临床特点分析

目的对中国华东地区26例临床确诊为家族性肌萎缩侧索硬化症(FALS)家系的先证者进行铜锌超氧化物歧化酶(SOD1)的基因突变筛查。方法收集26例FALS家系先证者的外周血样本及临床资料。采用PCR技术结合DNA直接测序法对外周血DNA进行SOD1基因5个外显子的突变筛查,并分析SOD1基因突变与临床表型的关系。结果有6例先证者检测出3种SOD1突变。其中3例为位于2号外显子的已知错义突变p.His46Arg(c.140AG),均表现为单侧下肢远端起病,上运动神经元损害不明显,平均病程可达10年以上。2例为位于2号外显子的已知错义突变p.Val47Ala(c.143TC),临床表型较复杂,病变进展相对较快。1例为位于2号外显子新的错义突变p.Gly37Arg(c.112GC),单侧上肢远端起病,上下运动神经元均受损,进展缓慢。结论中国华东地区FALS患者中SOD1基因突变仍占首位,突变与临床表型相关,其中His46Arg的临床表型具有特征性,有助于疾病预后判断。     

中国肾上腺脑白质营养不良患者中一个新的ABCD1基因突变的鉴定

目的鉴定并分析1个新的肾上腺脑白质营养不良家系的基因突变类型和位点.方法采用长链RT-PCR技术,从外周血提取总RNA并合成cDNA,以cDNA为模板,分4个片段扩增致病基因编码区,将纯化后的PCR产物直接测序,找出基因突变的位点.同时应用限制性酶切分析的方法,分析发病家系所有成员的基因组DNA,以证实所发现的突变.结果患者肾上腺脑白质营养不良基因外显子2上的第343位密码子发生了GGC→GTC改变,使原来编码的甘氨酸被缬氨酸(G343V)取代;患者母亲为G343V突变携带者,患者哥哥的基因型和患者完全相同,其父亲为正常基因型.结论在中国人肾上腺脑白质营养不良患者中发现一个新的ABCD1基因突变,即G343V突变.     

DMD基因新发错义突变致Becker型肌营养不良症一家系临床表型及基因突变分析

目的总结DMD基因新发错义突变导致的Becker型肌营养不良症一家系临床表型及基因突变特点。方法与结果采用第二代测序技术对1例25岁男性Becker型肌营养不良症患者进行基因检测,Sanger测序进一步验证患者之母和妹DMD基因c.4449T G(p.Asn1483Lys)位点,并结合患者及其家族成员的临床资料进行分析。结果显示,患者及其两位舅父具有相同的临床表型,双小腿肌肉呈假性肥大,双下肢近端肌萎缩和肌无力,血清肌酸激酶水平升高。患者基因检测DMD基因外显子34c.4449T G(p.Asn1483Lys)为错义突变,经检索为新发突变,其母和妹为携带者,结合患者两位舅父临床表现,确诊为Becker型肌营养不良症,该家系为Becker型肌营养不良症家系且存在该基因突变位点的共分离现象。结论 DMD基因外显子34 c.4449T G(p.Asn1483Lys)为新发错义突变,丰富了DMD基因突变谱,为该家系遗传咨询和产前诊断提供了有价值的信息。     

Becker型肌营养不良症的限制性片段长度多态连锁分析

本文收集确诊的9个BMD家系,检出25例患者,平均发病年龄6.25岁,瘫痪年龄23.43岁,最年长者51岁。有4个家系接受RFLPs分析。在4个有多态信息的BMD基因内部探针检测中,共排除和确定携带者19人,确定2个家系基因突变的起源。并根据基因缺失和重组关系,将突变位点进行了区域定位,结论是BMD突变位点有多样性。     

A novel exon 5 mutation (N139H) in the SOD1 gene in a Spanish family associated with incomplete penetrance

BACKGROUND: Allelic heterogeneity and phenotype variability-especially in age at onset, penetrance and progression-are reported in ALS1 families. For this reason, SOD1 gene mutation data in ALS1 patients are currently being gathered to better understand the genotype-phenotype relationship in this disorder. Here, we report the clinical and molecular characteristics of a Spanish ALS1 family with incomplete penetrance. PATIENTS AND METHODS: Clinical data including age at onset, initial topography, progression and survival were available in three affected members. Erythrocyte SOD1 activity was measured in four individuals. Analysis of the SOD1 gene was performed by PCR and direct sequencing. RESULTS: A novel missense mutation in the exon 5 of the SOD1 gene, an A-to-C transversion at nucleotide position 1485 leading to N139H residue change, was identified in three family members. The phenotype was similar in all cases, with initial symptoms in the distal limb muscles and a mean survival time of around 4 years. Incomplete penetrance was observed in our family, as two obligate carriers did not develop any symptoms of amyotrophic lateral sclerosis (ALS). CONCLUSIONS: N139H is the fifth SOD1 gene mutation reported in Spain, and the first one presenting with incomplete penetrance. Genetic counseling for at-risk relatives in these low-penetrance families could be difficult as some individuals harbouring the mutation remain asymptomatic throughout their lives. Further genetic characterisation of ALS1 families should provide information regarding the distribution of SOD1 mutants in different ethnic groups.     

A rare Cu/Zn superoxide dismutase mutation causing familial amyotrophic lateral sclerosis with variable age of onset and incomplete penetrance in China.

More than 100 mutations in the Cu/Zn superoxide dismutase (SOD) gene have been found, accounting for about 20% of familial ALS (FALS). However, few have been identified in Chinese patients with FALS. We present a five-generation Chinese family with FALS with a rare mutation in exon 4 of the Cu/Zn SOD gene codon position 105, converting serine to leucine. Forty-seven family members including the proband were examined clinically; two affected persons had EMG and nerve conduction studies. Genomic DNA was extracted from peripheral blood leukocytes of the family members after informed consent. All five exons of the Cu/Zn SOD gene were amplified by polymerase chain reaction (PCR) and DNA sequencing was performed on purified products. Exon 4 of the Cu/Zn SOD gene was amplified from genomic DNA isolated from not only the family members but also from 50 unrelated healthy Chinese control subjects. A rare S105L mutation, which is heterozygous with C by T at position 1,125 of the coding sequence in exon 4 of the Cu/Zn SOD gene, was found in the proband and her affected elder brother. The clinical phenotype within the FALS patients in this family is relatively variable. The age at onset ranged from 32 to 65 years, with initial symptoms in either the upper or lower extremities in different family members. Two subjects aged 72 and 60 years remained asymptomatic until their death from other causes, although their offspring carrying the same mutation have already developed clinical evidence of the disease. The S105L mutation was identified in another seven asymptomatic family members, aged 7 to 59 years. It is concluded that the S105L mutation in exon 4 of the Cu/Zn SOD gene is pathogenic. The phenotype is characterized by relatively variable clinical symptoms, with incomplete penetrance.     

Identification of Tau and SOD1 gene mutation in a small Chinese Han pedigree of adult amyotrophic lateral sclerosis

We report the clinical profile, and a brief investigation of SOD1 and Tau gene mutation from a small Chinese Han pedigree of adults with amyotrophic lateral sclerosis (ALS), which consisted of 32 familial members with 6 affected individuals spanning five generations, and presenting autosomal dominant genetic mode. The mean age of onset was 36.6 ± 15.9 years, and disease duration was 6 months to more than 5 years, the average survival was 16.1 ± 8.2 months. There were 5 patients with an early disease onset, rapid progressive course and short survival, and 1 patient with late onset, slow progressive course and long survival in the kindred. ALS patients began to suffer with weakness and muscle atrophy in one side of a lower extremity, which then spread to the upper extremity, the opposite side and bulbar muscles. All patients had spinal onset type. Muscle stretch reflexes were absent or weak in the upper limbs and accentuation in the lower limbs; pathological signs in the lower limbs were positive. Electromyography disclosed ongoing denervation muscle potentials in the four extremities. Brain and spinal MRI did not show any abnormal signal. A 5 exons mutation of SOD1 in all affected individuals was identified using SSCP. Polymorphisms of partial risk regions in 3′,5′ UTR, and in introns 9, 10, 11, 12 of the Tau gene in the affected and normal family members and in 70 healthy controls were examined by DNA sequencing. Routine exons mutation of SOD1 was not detected, but one single nucleotide polymorphism of A to G at 138278 at 3′ UTR of the Tau gene was shown to significantly over-express in fALS familial members.     

A clinical variance in familial amyotrophic lateral sclerosis with a point mutation in Cu/Zn superoxide dismutase gene

We report here a novel point mutation in exon 5 of the Cu/Zn superoxide dismutase (SOD) gene resulting in an amino acid substitution of valine¹⁴⁸ by isoleucine (V148I) in a Japanese family with amyotrophic lateral sclerosis (FALS). In this family, the age at onset was young (28.0 ± 3.8 years old, mean ± SD, n = 4) and the disease progression was rapid (22.0 ± 5.9 months, n = 3) with low Cu/Zn SOD activity (56.3 and 59.0% of the controls, n = 2). It is interesting that the clinical features of ALS varied very much among the affected members. One case had weakness of the lower extremities at first, and died without bulbar paresis. The second case first noticed wasting of the upper limbs with bulbar symptoms, but the third had weakness of upper extremities without developing dysarthria nor dysphagia until death. The living remainder first developed fasciculation of the tongue without weakness of extremities. The valine¹⁴⁸ is conserved among different species, and V148I mutation might destabilize dimer formation with another SOD subunit, leading to decrease enzymatic activity. These results suggested that there could be considerable clinical variance among the patients of FALS within one family, carrying the same Cu/Zn SOD mutation such as V148I.     

Clustering of ALS patients in central Italy due to the occurrence of the L84F SOD1 gene mutation.

OBJECTIVE: To study three new apparently unrelated Italian families with ALS and several sporadic ALS patients living in the same rural area. BACKGROUND: One Italian family with ALS carrying a superoxide dismutase 1 (SOD1) gene mutation (G41S) and no regional ALS clustering has been reported in Italy. METHODS: Genetic analysis was performed by automated and manual sequencing of the SOD1 gene in 13 family members and in 6 of 10 unrelated patients with sporadic cases of ALS living in the same area. The authors also determined SOD1 activity in erythrocytes and lymphocytes. RESULTS: The three families included a total of 28 affected members distributed over six generations. Despite a wide variability in age at onset and disease duration, the clinical pattern is uniform, with onset in the lower limbs, ascending progression, and predominant lower motor neuron involvement in all subjects. Generational anticipation is evident in the last two generations. All familial ALS patients and one of the six sporadic patients carry the same L84F missense point mutation in exon 4 of the SOD1 gene. SOD1 enzyme activity and SOD1 protein levels were not decreased significantly in the L84F patients. CONCLUSION: The ALS patients carrying the L84F mutation derive from a common ancestor. This mutation is responsible for ALS clustering in the area. The L84F mutation does not modify SOD1-specific activity.     

Detection of preclinical motor neurone loss in SOD1 mutation carriers using motor unit number estimation

OBJECTIVE: To determine the pattern of motor neurone loss in amyotrophic lateral sclerosis (ALS). In particular, to determine whether there is a gradual life long presymptomatic motor neurone loss or, alternatively, a sudden catastrophic loss just before the onset of symptoms. METHOD: The statistical motor unit number estimation (MUNE) technique was used in a longitudinal study of 19 asymptomatic carriers of the Cu, Zn superoxide dismutase 1 (SOD1) gene. MUNE results were compared with those of 34 age and sex matched SOD1 negative family controls and 23 population controls. Motor neurone loss was also estimated in 12 patients with sporadic ALS. 84 subjects (43 male and 41 female patients) with an age range from 16-73 years were followed up over three years, both clinically and by MUNE, every six months. RESULTS: In 2 of the 19 mutation carriers, there was a sudden reduction in MUNE several months before the onset of weakness. The patients with symptomatic sporadic ALS also had a reduced MUNE, but there was no detectable loss of motor neurones in the remainder of the subjects. CONCLUSION: MUNE can be used to detect preclinical loss of motor units in familial ALS. Normal numbers of motor neurones were maintained in 17 SOD1 mutation carriers over the three year period. There was an abrupt loss of motor neurones just before the onset of symptomatic weakness in two SOD1 mutation carriers. These results suggest that some form of trigger may initiate rapid cell loss and death of motor neurones just before the onset of symptoms.     

A novel SOD1 gene mutation in a Korean family with amyotrophic lateral sclerosis

BACKGROUND: Superoxide dismutase 1 (SOD1) gene mutations are responsible for approximately 20% of all familial amyotrophic lateral sclerosis (ALS) cases. However, these cases, especially those with SOD1 gene mutations, have not been reported in Korea. OBJECTIVES: The SOD1 gene in Korean family with ALS was screened for potential mutations and the clinical data was collected. MATERIALS AND METHODS: The clinical histories and neurological findings of the family members were obtained. Genomic DNA was isolated from the leukocytes of whole blood samples and the coding region of the SOD1 gene was analyzed by PCR and sequencing. RESULTS: The family with ALS showed a novel missense mutation in the SOD1 gene, which was heterozygous for the mutation, GGC to GTT, causing the substitution of valine for glycine at codon 10 (Gly10Val) in exon 1. Clinically, the patients exhibited early onset and rapid disease progression. CONCLUSIONS: Familial ALS with a novel Gly10Val mutation in the SOD1 gene showed severe clinical features. The mutation lies in a region involved in a dimer contact in the three-dimensional structure of the SOD1 protein. This study expands the number of ALS-associated SOD1 gene mutations.     

ALS with variable phenotypes in a six-generation family caused by leu144phe mutation in the SOD1 gene.

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive neurological disorder. The mutations of Cu/Zn superoxide dismutase gene (SOD1) are responsible for familial ALS. We investigated a large family of Istro-Rumanian origin characterized by an autosomal dominant ALS occurring in 18 cases (three of which are still alive) throughout six generations. METHODS: Clinical data were available for nine patients from the 2nd generation onward, among which one contained the neuropathological details. The mean age at onset of the disease (+/-SD) was 57.3+/-8.9 years (range 49-72), while the duration of the disease spanned over a length of time equal to 4.9+/-1.96 years (range 1.5-7). The analysis of the coding region of SOD1 was done by PCR and direct sequencing. The SOD1 activity was measured by using the red and mononuclear cells belonging to three of the patients. RESULTS: The leu144phe mutation of SOD1 was identified in four patients while a normal sequence was found in five healthy related subjects. The molecular defect was responsible for a decrease in SOD1 activity. Most of patients in this family presented clinical manifestations of ALS (in particular, the lower limb onset variant) not as severe as typical ALS caused by other SOD1 mutations. However, one patient suffering from hyperthyroidism for 17 years, showed an early onset and a rapidly progressing ALS coupled with dementia. CONCLUSIONS: We described a large family with a relatively not severe phenotype of ALS (due to a leu144phe SOD1 mutation) that was compromised in one patient by a concomitant hyperthyroidism.     

The G93C mutation in superoxide dismutase 1: clinicopathologic phenotype and prognosis

BACKGROUND: Twenty percent of familial amyotrophic lateral sclerosis (ALS) is caused by mutations in the superoxide dismutase 1 gene (SOD1). Few data exist on their clinicopathologic phenotypes. OBJECTIVES: To determine the clinical and pathologic phenotype associated with the G93C mutation in SOD1 and to compare survival in familial ALS related to this mutation with survival in other ALS subgroups. DESIGN: Retrospective study. SETTING: Tertiary referral center for neuromuscular disorders. PATIENTS: Twenty patients with the G93C mutation for whom clinical data were available and 1 patient with pathologic data. MAIN OUTCOME MEASURES: Characteristics and survival compared with other ALS subgroups, adjusting for known prognostic factors. RESULTS: The G93C mutation was associated with a purely lower motor neuron phenotype without bulbar involvement. Presence of the mutation independently predicted longer survival compared with other ALS subgroups. Pathologic examination showed degeneration of the anterior horn, spinocerebellar tracts, and posterior funiculi, with minimal involvement of corticospinal tracts and no degeneration of brainstem motor nuclei. Survival motor neuron gene copy number had no significant influence on age at onset or survival in patients with the G93C mutation. CONCLUSIONS: These findings add to the knowledge of SOD1-related familial ALS and demonstrate further clinicopathologic variability between different SOD1 mutations. Finally, they demonstrate the independent prognostic value of the G93C mutation.