晚发型cblC型甲基丙二酸尿症合并同型半胱氨酸血症1例报告并文献复习

目的 探讨晚发型甲基丙二酸尿症合并同型半胱氨酸血症的临床及基因变异特点。方法 回顾性分析1例MMACHC基因突变致晚发型cblC型甲基丙二酸尿症合并同型半胱氨酸血症患者的临床资料及基因检测结果，并结合文献讨论。结果 本例男性患者，以双足麻木起病，逐渐出现双下肢僵硬无力，发病前有非特异性精神行为异常症状，此次就诊经基因检测发现MMACHC基因4号外显子存在c. 482G>A(p. Arg161Gln)错义突变，与文献报道c. 482G>A复合杂合突变不同，本例患者突变类型为纯合突变。结论 甲基丙二酸尿症合并同型半胱氨酸血症的临床异质性较大，容易漏诊误诊，当出现不明原因的精神行为异常时应考虑该诊断，基因检测是诊断的重要依据，同时也可指导该病的分型。     

维生素B_(12)依赖型甲基丙二酸血症一家系临床表型和基因突变分析及疗效评价

目的探讨维生素B_(12)依赖型甲基丙二酸血症家系临床特点、基因突变和维生素B_(12)治疗效果。方法采集一维生素B_(12)依赖型甲基丙二酸血症家系共4名成员临床资料,抽取外周静脉血行血浆氨基酸和酰基肉碱谱分析及基因检测,评价维生素B_(12)治疗效果。结果家系中先证者12岁发病,以学习成绩下降、性格改变为首发症状,病程中出现幻觉、双下肢无力;先证者之弟主要表现为易怒、学习成绩较差。经血浆氨基酸和酰基肉碱谱分析,先证者及其弟血浆丙酰肉碱、丙酰肉碱/乙酰肉碱比值升高,尿液甲基丙二酸水平升高。基因检测显示,先证者及其弟均存在MMACHC基因复合杂合突变c.482GA(p.Arg161Gln)和c.609GA(p.Trp203X),其父携带MMACHC基因错义突变c.482GA(p.Arg161Gln),其母携带MMACHC基因无义突变c.609GA(p.Trp203X)。经维生素B_(12)治疗后均症状好转。结论晚发型维生素B_(12)依赖型甲基丙二酸血症系MMACHC基因复合杂合突变所致,维生素B_(12)治疗反应良好,早期诊断、及时治疗对患者预后意义重大。     

MYOT基因变异相关肌原纤维肌病3型的临床、肌肉病理和分子遗传学分析

目的对MYOT基因突变致肌原纤维肌病3型的临床表型特点、肌肉病理、基因突变及相关蛋白进行分析, 并对该病进行文献复习和综述。方法回顾分析2018年12月于山东大学齐鲁医院确诊的1例MYOT基因突变致肌原纤维肌病3型患者的临床表型特点、肌肉病理和基因检测结果。应用全外显子测序对患者进行高通量致病基因筛查, 发现候选致病突变后应用Sanger测序技术对患者及家系成员进行突变位点的验证, 同时对发现的MYOT的基因突变位点进行功能学验证并结合相关文献进行复习综述。结果该患者为47岁女性, 因双下肢无力8年就诊。肌电图检查示肌源性损害;肌肉病理提示部分肌纤维内异常物质沉积及镶边空泡。外显子组测序和Sanger测序发现患者携带MYOT基因c.170C>T(p.Thr57Ile)杂合突变, 其儿子、女儿也存在着相同的突变位点。患者儿子肌酸激酶水平升高, 肌电图偶见自发电位, 患者女儿无异常;患者2名弟弟未检测到上述变异位点。蛋白功能研究提示MYOT基因c.170C>T突变可导致myotilin的部分空间结构发生改变, 且p62蛋白与myotilin的异常聚集参与疾病的致病过程。经文献复...     

晚发型甲基丙二酸尿症cblC型家系快速诊断、治疗与随诊

目的总结晚发型甲基丙二酸尿症cblC型两家系4例患儿临床表型、治疗原则及预后,探讨其病理生理学机制。方法与结果采用外显子组测序技术快速诊断晚发型甲基丙二酸尿症cblC型两家系。家系1姊妹存在MMACHC基因外显子4 c.482G A(p.Arg161Gln)和c.615C A(p.Tyr205X)复合杂合突变,分别来自其父母。先证者主要表现为智力减退、下肢痉挛性运动障碍伴癫发作;其妹则呈现以轴索损害为主的四肢周围神经病变和视神经萎缩,而智力减退症状相对较轻。家系2兄妹存在MMACHC基因外显子4 c.440_441del(p.Gly147fs)和c.482GA(p.Arg161Gln)复合杂合突变,分别来自其父母。先证者表现为智力减退、精神行为异常和双下肢无力伴锥体束征,呈髓鞘和轴索混合性损害的周围神经病变;其妹症状相似但发病年龄较早。采用维生素B12、叶酸、左卡尼汀等药物联合治疗6个月患儿智力水平明显提高、癫发作得以控制,但均遗留不同程度双下肢运动障碍。结论晚发型甲基丙二酸尿症cblC型临床表现复杂多样,可广泛累及大脑皮质、锥体束、锥体外系、周围神经等,目标区域捕获联合第二代测序技术可以快速明确诊断,早期诊断、积极治疗对改善患者预后至关重要。     

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。     

Parkin基因复合杂合突变的早发型帕金森病的临床特点(附1例报告)

目的探讨Parkin基因复合杂合突变的早发型帕金森病的临床特点。方法回顾性分析1例Parkin基因复合杂合突变早发型帕金森病患者的临床资料,并进行文献复习。结果患者为47岁女性,24年前开始出现运动迟缓、四肢僵硬、震颤。全外显子组基因检测显示,患者Parkin基因存在2处基因突变,c.8TA杂合突变导致其编码蛋白发送p.V3E错义突变;c.850GC杂合突变导致其编码蛋白发生p.G284R错义突变。家系验证结果显示,两处突变分别来自于父母,其余直系亲属均只携带一处杂合突变。结论 Parkin基因复合杂合突变的早发型帕金森病患者表现为逐渐进展的四肢僵硬、震颤、运动迟缓为主的运动症状。Parkin基因复合杂合突变导致的编码蛋白错义突变可能是PD的重要病因。     

短链烯酰辅酶A水合酶1基因突变导致线粒体短链烯酰辅酶A水合酶1缺乏症1例

目的总结1例短链烯酰辅酶A水合酶1(ECHS1)基因导致线粒体短链烯酰辅酶A水合酶1缺乏症(ECHS1D)患儿的临床特征及基因突变特点。方法回顾性分析2021年1月就诊于徐州市儿童医院神经内科的1例ECHS1D患儿的临床特点及基因检测结果, 并通过检索国内外相关文献对该疾病的临床特征进行复习。结果患儿男性, 年龄6个月4 d, 急性起病, 临床以肢体活动障碍为主要表现。患儿运动发育迟缓, 竖头尚可, 不能翻身、独坐, 不能追视, 不能逗笑出声, 四肢肌张力增高。入院检查示血乳酸水平升高至6.2 mmol/L, 提示代谢性酸中毒。头颅磁共振成像(MRI)示双侧基底节区异常信号, 左侧大脑半球脑膜异常强化。全外显子组测序发现该患儿ECHS1基因存在复合杂合突变, 分别为c.563C>T(p.A188V)和c.5C>T(p.A2V), 患儿父亲携带c.563C>T突变, 母亲携带c.5C>T突变, 均为错义突变。结论 ECHS1基因以错义突变为主, 大部分为复合杂合突变, 少部分为纯合突变。ECHS1基因突变导致线粒体ECHS1D常累及婴幼儿, 发病相对较早, 临床表...     

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。     

贵州部分少数民族遗传性痉挛性截瘫Spastin基因突变研究

目的筛查及分析遗传性痉挛性截瘫(HSP)Spastin基因突变,了解贵州地区少数民族(彝族、布衣族、苗族)Spastin基因突变特点。方法应用PCR产物直接DNA测序法,对9例HSP患者(包括3个家系中7例现证者和2例散发患者)Spastin基因1-17号外显子进行突变筛查;被发现存在突变的外显子,其次行家系内其他成员相对应外显子的筛查。结果在9例HSP患者中发现家系3两例患者(Ⅴ24、Ⅴ25)的Spastin基因第4号外显子同一位点上发生错义突变c.847C>T,其他参与抽血的亲属均无该位点突变,推测该位点的突变为一多态。另外的突变位点均位于外显子序列前后的内含子区域。结论此次贵州地区部分少数民族spastin基因突变率低,与国内文献报道的汉族人群不同。     

拉莫三嗪治疗Becker型先天性肌强直一例并文献复习

目的报道拉莫三嗪治疗1例Becker型先天性肌强直患者的疗效及安全性。方法与结果17岁男性患者,以四肢肌肉僵硬为首发症状,反复运动后症状减轻,血清肌酸激酶水平正常,基因检测提示存在CLCN1基因外显子11 c.1205C T(p.Ala402Val)及CLCN1基因外显子8 c.896T C(p.Val299Ala)错义突变,确诊为Becker型先天性肌强直;其母为CLCN1基因外显子11 c.1205C T(p.Ala402Val)、其父为CLCN1基因外显子8 c.896T C(p.Val299Ala)错义突变,确诊为Becker型先天性肌强直家系,其中CLCN1基因外显子8 c.896T C突变尚无报道。经拉莫三嗪连续治疗5年后肌强直症状长期缓解,且无任何药物不良反应。结论该例CLCN1基因外显子8 c.896T C错义突变进一步扩展了CLCN1基因突变谱。拉莫三嗪治疗效果良好,为Becker型先天性肌强直的治疗提供了新的思路。     

以小脑损害为主要表现的成人甲基丙二酸血症合并高同型半胱氨酸血症一例

报告1例成年起病的甲基丙二酸血症合并高同型半胱氨酸血症患者的临床资料。患者为男性,24岁发病,以行走不稳、精神行为异常起病,进行性加重,神经系统体检发现明显的小脑性共济失调及锥体束征,头颅磁共振成像显示双侧小脑半球对称性长T2信号,血液总同型半胱氨酸、尿甲基丙二酸水平显著增高,基因检测发现MMACHC基因复合杂合突变c.482G>A及c.217C>T,确诊为钴胺素C缺乏症。经给予腺苷钴胺、甜菜碱、叶酸、左卡尼汀治疗后患者行走不稳略有所好转,血同型半胱氨酸水平也显著下降。     

Clinical and biochemical studies on Chinese patients with methylmalonic aciduria

Methylmalonic aciduria is a common organic aciduria disease. Recently, gas chromatography-mass spectrometry has been used to diagnose methylmalonic aciduria in China. Often, however, the diagnosis of methylmalonic aciduria is delayed because of a lack of technical expertise and the limited experience of general clinicians in China. In this study, the natural history, clinical features, and outcome of 77 Chinese patients with methylmalonic aciduria were investigated. Of the 77 patients, 31 (40.3%) had isolated methylmalonic aciduria and 46 (59.7%) had methylmalonic aciduria combined with homocystinemia. Thus, we observed a higher rate of the combined disease than studies conducted in other countries, suggesting that it might be more common in China. Total plasma homocysteine measurement might enable differential diagnoses of methylmalonic aciduria to be distinguished. The clinical spectrum of these 77 patients with methylmalonic aciduria ranged from neonatal death and severe symptoms to benign asymptomatic organic aciduria. Neonatal and infantile onset, which was a characteristic of the majority of cases, was associated with a greater severity relative to later-onset cases. Among the 17 cases who had onset after 3 years of age, only 1 patient had isolated methylmalonic aciduria and 16 had combined methylmalonic aciduria and homocystinemia. Nine of the patients with combined methylmalonic aciduria and homocystinemia completely recovered and exhibited normal intelligence, whereas seven improved, with a mild handicap.     

ARSA gene mutations in five Chinese metachromatic leukodystrophy patients

The objective was to identify arylsulfatase A mutations, if any, in five Chinese patients with metachromatic leukodystrophy. This would be the first such study in China. All eight exons and exon-intron boundaries of the arylsulfatase A gene (ARSA) were amplified with polymerase chain reaction, which was followed by direct DNA sequencing. Patient 1 exhibited a homozygous mutation at c.954G>A (p.W318X) in exon 5. Patient 2 exhibited compound heterozygous mutations, identified as one allele with the c.862C>T (p.R288C) missense mutation in exon 5 and the other allele with the c.1338dupC frameshift mutation in exon 8. Patient 3 exhibited only a c.179_180dupCA frameshift mutation in exon 1 in one allele. Patients 4 and 5 exhibited identical compound heterozygous mutations, identified as one allele with the c.296G>T (p.G99V) missense mutation and the other allele with the c.251G>A (p.R84Q) missense mutation in exon 2. Six DNA variants of the arylsulfatase A gene were identified: two novel frameshift mutations (c.179_180dupCA and c.1338dupC), one known nonsense mutation (p.W318X), and three known missense mutations (p.R84Q, p.G99V, and p.R288C).     

Tracing the Origin of L-2-Hydroxyglutaric Aciduria in a Family

We describe late diagnosis of an adult with L-2-hydroxyglutaric aciduria (MIM 236792) on the basis of characteristic metabolite data and mutation analysis in the L2HGDH gene. The patient lacked MRI abnormalities which have been purported to be constant or typical findings in this disease. We further report the genetic status of his parents and his one living sibling. Our observations underline the clinical heterogeneity of the syndrome of L-2-hydroxyglutaric aciduria. This report emphasizes the diagnostic benefit of the assessment of urinary organic acids not only in children, but also in adult patients with unexplained neurological symptoms. The patient was determined to be compound heterozygous for two novel missense mutations in exon 4 of the gene (c.418G>C, c.446T>G), resulting in amino acid exchanges from alanine to proline (p.Ala140Pro) and leucine to arginine (p.Leu149Arg), respectively. The mother of our patient was heterozygous for Ala140Pro, and the father heterozygous for Leu149Arg only. Mutation analysis of a healthy 49-year-old third son of the non-consanguineous parents revealed a normal exon 4.     

CLN5基因复合杂合突变致青少年型神经元腊样脂褐质沉积症的临床特征及基因分析

目的报道及分析CLN5基因复合杂合突变致青少年型神经元腊样脂褐质沉积症(JNCL)患者的临床特征和基因突变类型。方法观察分析1例JNCL病人的临床表现、影像学、脑电图改变,进行全外显子组基因测序,并对其家庭成员进行相关基因检测和临床检查。结果患者于6岁开始视力减退及智力倒退,9岁出现肌阵挛发作、行走不稳。头颅MRI显示小脑明显萎缩,大脑皮质和脑干轻度萎缩。视频脑电图显示弥漫性2.5~3.5 Hz慢活动及颞区尖波。全外显子测序发现患者CLN5等位基因上1个来源于父亲的错义突变:exon2 c.376TC,以及1个来源于母亲的无义突变:exon3 c.595 CT。患儿父亲及弟弟均有c.376 TC突变,两人体查均发现水平性及旋转性眼震,该位点突变目前尚未见报道。结论 CLN5基因c.376TC和c.595CT的复合杂合突变可以引起JNCL临床症状、影像学和脑电图改变。对于NCL可疑病例应该对患者及家族成员及早进行相关基因测序明确其基因型,并实施生育指导。     

Mutations in phenotypically mild D-2-hydroxyglutaric aciduria

D-2-hydroxyglutaric aciduria is a neurometabolic disorder with mild and severe phenotypes. Recently, we reported pathogenic mutations in the D-2-hydroxyglutarate dehydrogenase gene as the cause of the severe phenotype of D-2-hydroxyglutaric aciduria in two patients. Here, we report two novel pathogenic mutations in this gene in one patient with a mild presentation and two asymptomatic siblings with D-2-hydroxyglutaric aciduria from two unrelated consanguineous Palestinian families: a splice error (IVS4-2A-->G) and a missense mutation (c.1315A-->G;p.Asn439Asp). Overexpression of this mutant protein showed marked reduction of the enzyme activity.     

Adult onset glutaric aciduria type I presenting with a leukoencephalopathy

Glutaric aciduria type I usually presents with an acute metabolic crisis during infancy. The authors report a previously healthy 19-year-old woman who presented with recurrent headaches, oculomotor symptoms, and a severe leukoencephalopathy on MRI. The diagnosis was made by urinary organic acid analysis and confirmed by enzyme studies. Genetic analysis revealed compound heterozygosity with a deletion c.219delC in exon 3 and a novel missense mutation R132G in exon 5 of the glutaryl CoA dehydrogenase (GCDH) gene.     

中国南方汉族散发早发性帕金森综合征的parkin基因突变分析

目的 探讨中国南方汉族散发早发性帕金森综合征(early onset parkinsonism,EOP)的parkin基因突变特点.方法 应用实时荧光定量PCR技术结合DNA直接测序技术对156例中国南方汉族散发EOP患者进行parkin基因突变分析.结果 19例患者parkin基因突变,包括15例杂合突变、2例纯合突变、2例复杂杂合突变.17例患者外显子重排突变,其中12例外显子缺失突变,5例外显子双重重复突变.此外,3例患者存在点突变和(或)小片段缺失突变,其中ⅣS9+18C＞T、c.202-203delAG为已报道突变,c.813delT为未报道的新突变;parkin基因突变位点主要分布在其1～7号外显子.无parkin基因突变与有parkin基因突变的患者在临床表现及病情严重程度方面差异无统计学意义,但发病年龄[(40.9±6.8)岁与(35.5±10.0)岁,Z=-2.271,P=0.023)]、病程[(4.4±3.6)年与(7.6±4.0)年,Z=-3.680,P=0.000)]等方面差异有统计学意义.结论 中国南方汉族散发EOP患者parkin基因突变的频率为12.18%(19/156),外显子重排突变是其重要突变类型;外显子缺失突变是主要的突变形式;parkin基因1～7号外显子为突变热点.parkin基因突变与无parkin基因突变的EOP患者在临床表型上无明显差异,但其发病年龄较轻,病程较长,进展较缓慢.