假肥大型肌营养不良症肌电图表现

目的：总结假肥大型肌营养不良症（DMD）患儿的肌电图特点及其对DMD的诊断价值.方法：对13例DMD患儿的临床特征及病因进行分析,并做神经传导和肌电图（EMG）检测.结果：DMD好发于儿童,以进行性、对称性肌萎缩和肌无力及肢体近端型的特殊分布特点,肌电图呈肌源性改变.结论：肌电图对DMD的临床诊断有重要价值.     

假肥大型肌营养不良症基因诊断及遗传分析

目的对假肥大型肌营养不良症（DMD／BMD）患者进行基因诊断并对家系进行遗传分析,以提高对DMD／BMD的基因诊断水平及有效的遗传咨询。方法对40例DMD／BMD患者应用18对引物多重PCR技术进行Dystrophin基因缺失诊断,收集完整家系资料进行遗传分析以判断致病基因携带者及评估风险。结果40例DMD／BMD患者基因诊断有27例至少存在一个外显子片段缺失（67．5％）,13例未检测到缺失（32．5％）。通过对家系的遗传分析判断出致病基因携带者。结论多重PCR作为一种简便快速的诊断方法可对DMD／BMD患者进行基因诊断;对风险家系进行遗传分析、判断致病基因携带者以进行有效的遗传咨询,进而控制遗传病。     

脐血干细胞移植治疗假肥大型肌营养不良症

目的比较假肥大型肌营养不良症(Duchennemusculardystrophy,DMD)患者经脐血干细胞移植治疗前后其肌肉再生、抗肌萎缩蛋白表达和运动功能的改变;以及评价治疗的安全性。方法对1例经基因分析和肌肉活检及抗肌萎缩蛋白检测确诊的、已丧失行走能力的DMD患儿,经HLA配型,在脐血库中寻找到一个全相合的脐血供体。采用白消安+环磷酰胺+兔抗胸腺淋巴细胞球蛋白预处理后进行异基因脐血干细胞移植;术后采用环孢素A和骁悉方案预防移植物抗宿主反应(graftversushostreaction,GVHD)。同时定期检测原发病的生化指标如血清肌酸激酶(creatinekinase,CK)、造血重建的植入证据(血型转变、肌肉和血液系统的聚合酶链反应短串联重复序列分析)、缺陷基因是否纠正、新生肌肉是否出现、肌肉中抗肌萎缩蛋白是否表达和运动功能是否改善。结果(1)中性粒细胞在脐血干细胞移植后第15天(+15天)达到0.5×109/L,白细胞在+25天达正常水平;血小板于+22天达到20×109/L;血红蛋白维持于85～100g/L。术后140天骨髓穿刺提示三系生长旺盛;(2)移植后140天血型转为供体AB型。至今没有出现移植物抗宿主反应。(3)术后18天、30天、43天、55天、74天、233天患者外周血DNA和术后140天、183天、235天骨髓细胞DNA经PCRSTR检测为供者独立植入;(4)患儿术后60天取外周血做基因分析,显示19号缺失的外显子得到完全纠正,患儿转变为正常基因型;(5)患儿在移植后75天的肌肉活检可见新生肌管形成,抗肌萎缩蛋白免疫组化呈弱阳性,少数为强阳性反应,DNA分析:供者基因DNA占1%～13%;移植后126天抗肌萎缩蛋白免疫组化检测显示阳性的肌纤维明显增多,供者基因DNA上升至2.5%～25%;(6)患儿血清CK从移植治疗前的5735U/L降至274U/L;(7)术后100天体检发现患儿肌力略有改善,肢端温暖。结论异基因脐血干细胞移植治疗DMD,可在移植后短期内重建造血功能、血清CK显著下降、肌肉抗肌萎缩蛋白表达,患儿运动有所改善,提示造血干细胞移植将有益于DMD的治疗。     

良性假肥大型肌营养不良一家系13例

先证者 (Ⅳ8)　男 ,5 2岁。 12岁时自感双下肢无力 ,跑跳落后于同龄人。 2 0岁时病情加重 ,双手抓握无力 ,走路呈“鸭步” ,仰卧时起立困难 ,3 8岁起瘫痪在床。查体 :双上肢肌肉、胸肩肌、腰肌、臀肌群明显萎缩 ,腓肠肌萎缩不明显 (早期肥大 ) ,手指肌腱及下肢肌腱挛缩。心、肺、腹未见明显异常。患者曾先后多次去济南、北京等医院就诊 ,诊断为良性假肥大型肌营养不良。家系调查 :调查 6代 ,患者 13人 ,均为男性。临床表现与先证者相同 ,但程度不同。已死亡 5人 ,死亡年龄 5 1～ 62岁 ,发病年龄最小 7岁 ,最大 2 0岁 (图 1)。图 1　患者家系…     

假肥大型肌营养不良基因诊断技术研究进展

假肥大型肌营养不良是由于Dystrophin基因突变而导致的X-连锁隐型遗传病,目前对这种疾病还没有有效的治疗方法。通过基因诊断技术对假肥大型肌营养不良患者以及携带者进行准确、全面的突变检测,进而进行产前诊断避免患儿的出生是目前解决这一问题的最有效途径。近几年来,一些常规的Dystrophin基因突变检测技术有了新的进展,同时也出现了一些全新的技术。该文对几种重要检测技术的研究进展进行综述。     

假肥大型肌营养不良症与HLA-A、B、DR等位基因的相关性研究

目的研究南方汉族人群中假肥大型肌营养不良症(Duchenne muscular dystrophy,DMD)患者的HLA-A、B、DR基因多态性,探讨免疫遗传因素在DMD发病机制及肌纤维坏死中的作用。方法采用PCR反向序列特异性寡核苷酸杂交技术(polymerase chain reaction-reverse sequence specific oligonucleotide,PCR-RSSO)和美国骨髓库编码软件(National Marrow Donor Program,NMDP),对113例DMD患者和406名健康对照的HLA-A、B、DR等位基因进行多态性分析。结果DMD组HLA-A24、A30等位基因的频率分别为11.25%和5.46%,与对照组的22.16%和0.87%相比差异有统计学意义(P=0.001,<0.01);DMD组HLA-B13、B15、B61、B62等位基因频率12.26%、16.92%、0.44%、0.44%,与对照组6.76%、1.49%、4.79%、5.05%相比差异有统计学意义(P=0.016,<0.01,0.001);DMD组HLA-DR04、DR07、DR12等位基因频率17.45%、6.40%、19.62%,与对照组10.67%、2.24%、11.92%相比差异有统计学意义(P=0.018,<0.01,0.012)。结论DMD患者HLA等基因表达与正常对照组有显著差异,HLA基因型可能与DMD的肌纤维坏死和发病机制相关。     

一例罕见的47,XXX女性假肥大型肌营养不良症

患者　女 ,10岁。因走路不稳易摔跤、上楼梯困难及小腿肥大就诊。患儿系足月顺产 ,生长发育较同龄儿童落后 ,智力、发育正常。查体 :神志清楚 ,皮肤巩膜无黄染 ,浅表淋巴结不肿大 ,心脏听诊无异常 ,肝、脾未触及。步态呈鸭步 ,躯干、骨盆和四肢的肌肉萎缩 ,翼状肌、小腿腓肠肌肥大 ,未引出病理反射 ,Gower's征阳性。心电图示心肌损害 ,右肱二头肌和右胫前肌肌电图显示肌源性损害。血液生化检显示患者肌酸激酶 10 10 3U / L (正常参考值 15～ 15 0 U/ L ) ,乳酸脱氢酶 6 4 3U/ L (正常参考值 180～ 4 30 U/ L ) ,谷草转氨酶 14 4 U/ L (…     

女性假肥大型肌营养不良症家系的临床病理和基因分析

目的研究女性假肥大型肌营养不良症(Duchenne muscular dystrophy，DMD)患者的临床特征，探讨其发病机理。方法对一个女性DMD家系患者的临床表现进行跟踪随访，并作肌肉组织的免疫组化检测及基因分析。结果该家系的DMD患儿临床表现及辅助检查均符合典型的DMD特征。先证者母亲的临床特点类似良性假性肥大型肌营养不良(Becker muscular dystrophy，BMD)，肌肉免疫荧光分析提示dystrophin蛋白染色阳性的纤维与阴性纤维并存。该家系的dystrophin基因分析为非缺失型。先证者母亲核型分析正常。结论本家系中的39岁女性具有类似BMD的临床表现，病理检查及图像分析提示dystrophin蛋白为正常的1／3。此例女性患者的核型分析正常，故倾斜的X染色体模式为其可能的机理。     

假肥大型肌营养不良症的基因突变和产前诊断研究

目的 了解中国人群DMD基因外显子突变的特点和产前诊断情况.方法 应用多重连接依赖性探针扩增技术(multiplex ligation-dependent probe amplification,MLPA)和变性高效液相色谱(denaturing high performance liquid chromatography,DHPLC)技术对Duchenne型假肥大型肌营养不良症(Duchenne muscular dystrophy,DMD)患者及胎儿进行DMD基因检测并对结果进行统计分析.结果 在388例DMD患者中发现缺失、重复和点突变3种突变类型,其中缺失突变230例,占59.28％,重复突变43例,占11.08％.共发现2个缺失热点区域,分别涉及第45～54外显子和第3～19外显子.重复突变主要位于第2～43外显子之间.发现点突变115例,占29.64％.对其中6例进行检测共发现5例点突变.在53例产前诊断中,共发现33例男胎,其中18例为患病胎儿.患病家庭在已知同意的前提下自主选择了终止妊娠.结论 中国人DMD基因的突变特点与国外报道一致.产前诊断可避免DMD患儿出生.     

假肥大型肌营养不良症15例家系的基因检测及产前诊断

目的 对15例假肥大型肌营养不良家系进行基因型分析.并为其家庭提供产前分子诊断评估再生育风险.方法 联合多重连接依赖性探针扩增(MLPA)检测和单体型连锁分析分别对15例家系行假肥大型肌营养不良(DMD)的DMD基因诊断.所有产前诊断标本均通过STR位点检测排除母血污染.结果 MLPA检测结果显示,15例先证者中DMD...     

进行性肌营养不良患者视网膜眼电图表型与临床分型及基因型的关系

目的 研究进行性肌营养不良（Duchenne/Becker muscular dystrophy,DMD/BMD)患者视网膜眼电图（electroretinogram,ERG)表型与临床分型以及基因型的关系。进一步探讨不同基因型的DMD患者抗肌营养不良蛋白（dystrophin)及其同源蛋白在视网膜上的表面爱功能,揭示DMD出现ERG异常的分子机理,方法 用11对引物对22例临床确诊的DMD／BMD患者作三步多重PCR进行基因缺失分析,并行ERG检查,结果 DMD／BMD患者ERG改变与临床分型及病情严重程度无关,与DMD／BMD的基因型有关,基因中央区缺失型的ERG异常率明显高于基因非缺失型,结论 DMD／BMD的ERG改变与DMD基因突变位点有关,可能DP260转录启动子与视网膜电信号的传导关系最密切。     

胰岛素依赖型糖尿病患者ApoE表型与基因型差异

为了研究胰岛素依赖型糖尿病（IDDM）患者载脂蛋白（Apo）E表型与基因型的差异，选择了中国汉族IDDM患者54例。采用等电聚焦法(IEF)和PCR/ASO探针杂交及扩增不应突变系统(ARMS)分别检测其ApoE表型和基因型。结果显示ApoE表型与PCR/ASO法分析的ApoE基因型差异14例(25.9%)，与ARMS法分析的ApoE基因型差异12例(22.2%)（P＜0.01）。相比之下，ApoE2异型频率相对增高(16.67%)。从而推断IDDM患者ApoE转录后的化学修饰可导致ApoE表型与基因型不一致。     

克隆缺失连接片段——一种基于PCR技术的缺失型假肥大型肌营养不良症的携带者检测

目的 依据dystrophin基因缺失后断端重接可形成一段变异的DNA序列,提出一种利用缺失连接片段进行缺失型假肥大型肌营养不良症携带者检测的新方法.方法 实验以来自广东省肇庆地区的一个Becker型肌营养不良(Becket muscular dystrophy,BMD)家系为研究对象,其中2例确诊的男性BMD患者,3例待诊的女性携带者,1例待诊的人工流产绒毛.先证者经外显子PCR检测确定第3～5外显子缺失,随后采用PCR步移法在相应内含子设计引物定位断裂点的位点,最后利用靠近断裂点设计的引物直接对家系的6例基因组DNA进行缺失连接片段的PCR扩增和测序.结果 6例基因组DNA均扩增出阳性的产物片段且连接片段的测序序列完全一致,绒毛的性别诊断结果为女性,可以确诊本家系中的3个女性和流产绒毛均为缺失型BMD携带者.结论 作者成功地将整个家系患者和携带者的缺失连接片段进行克隆和测序分析,实现了利用缺失连接片段对缺失型假肥大型肌营养不良症携带者进行准确基因诊断的设想,同时对在产前诊断上的应用前景进行了探讨.     

Cardiac dysrhythmias,cardiomyopathy and muscular dystrophy in patients with Emery-Dreifuss muscular dystrophy and limb-girdle muscular dystrophy type 1B

Emery-Dreifuss muscular dystrophy (EDMD) and limb-girdle muscular dystrophy type 1B (LGMD1B) are characterized by cardiac dysrhythmias, late-onset cardiomyopathy, slowly progressive skeletal myopathy and contractures of the neck, elbows and ankles. The causative mutation is either in the emerin gene (X-linked recessive EDMD) or lamin A/C gene (autosomal dominant EDMD2 or LGMD1B). We report three cases of EDMD, EDMD2 and LGMD1B. A 14-yr-old boy showed limitation of cervical flexion and contractures of both elbows and ankles. Sinus arrest with junctional escape beats was noted. He was diagnosed as X-linked recessive EDMD (MIM 310300). A 28-yr-old female showed severe wasting and weakness of humeroperoneal muscles. Marked limitation of cervical flexion and contractures of both elbows and ankles were noted. Varying degrees of AV block were noted. She was diagnosed as autosomal dominant EDMD2 (MIM 181350). A 41-yr-old female had contractures of both ankles and limb-girdle type muscular dystrophy. ECG revealed atrial tachycardia with high grade AV block. She was diagnosed as autosomal dominant LGMD1B (MIM 159001). Cardiac dysrhythmias in EDMD and LGMD1B include AV block, bradycardia, atrial tachycardia, atrial fibrillation, and atrial standstill, causing sudden death necessitating pacemaker implantation. Cardiologists should know about these unusual genetic diseases with conduction defects, especially in young adults.     

Relation between height and clinical course in Duchenne muscular dystrophy

We have evaluated the relation between height and rate of clinical progression in boys with Duchenne muscular dystrophy (DMD). In all, 111 DMD patients with age ranging from 2 to 23 years (mean 8.2 +/- 3.4 years) were assessed; of these patients, 92 had their height measured. Clinical course was determined through Vignos scale of functional disability, motor ability, and timed functional tests. All patients had grossly elevated serum creatine-kinase (CK) and pyruvate-kinase (PK) levels. When height was adjusted for patients' age, a statistically significant correlation was found between height and clinical course (positive with Vignos scale and negative with motor ability), suggesting that smaller boys have a better clinical course than taller patients of comparable age. These results support our previous hypothesis and suggest that growth inhibition seems to be effective in diminishing the progression of DMD.     

Correlation of clinical and deletion data in Duchenne and Becker muscular dystrophy.

Cloned cDNA sequences representing exons from the Duchenne/Becker muscular dystrophy (DMD/BMD) gene were used for deletion screening in a population of 287 males males affected with DMD or BMD. The clinical phenotypes of affected boys were classified into three clinical severity groups based on the age at which ambulation was lost. Boys in group 1 had DMD, losing ambulation before their 13th birthday; those in group 2 had disease of intermediate severity, losing ambulation between the ages of 13 and 16 years; and boys in group 3 had BMD, being ambulant beyond 16 years. A fourth group consisted of patients too young to be classified. Clinical group allocation was made without previous knowledge of the DNA results. A gene deletion was found in 124 cases where the clinical severity group of the affected boy was known. The extent of the deletions was delineated using cDNA probes. There were 74 different deletions. Fifty-five of these were unique to individual patients, but the other 19 were found in at least two unrelated patients. The different clinical groups showed generally similar distributions of deletions, and the number of exon bands deleted (that is, deletion size) was independent of phenotype. Some specific deletion types, however, correlated with the clinical severity of the disease. Deletion of exons containing HindIII fragments 33 and 34 and 33 to 35 were associated with BMD and were not found in patients with DMD. Deletions 3 to 7 occurred in four patients with the intermediate phenotype and one patient with BMD. Other shared deletions were associated with DMD, although in four cases patients with disease of intermediate severity apparently shared the same deletion with boys with DMD. The range of phenotypes observed, and the overlap at the genetic level between severe and intermediate and mild and intermediate forms of dystrophy, emphasizes the essential continuity of the clinical spectrum of DMD/BMD. There were no characteristic deletions found in boys with mental retardation or short stature which differed from deletions in affected boys without these features.     

Correlation between the phenotypes and genotypes of X-linked hypohidrotic ectodermal dysplasia and non-syndromic hypodontia caused by ectodysplasin-A mutations

Mutations in the ectodysplasin-A (EDA) gene can cause both X-linked hypohidrotic ectodermal dysplasia (XLHED) and non-syndromic hypodontia (NSH). The correlation between the phenotypes and genotypes of these two conditions has yet to be described. In the present study, 27 non-consanguineous Chinese XLHED subjects were screened and 17 EDA mutations were identified. In order to investigate the correlation between genotype and phenotype, we also reviewed related studies on NSH subjects with confirmed EDA mutations and compared the differences in the clinical manifestations and EDA mutations of the two conditions. Tooth agenesis was observed in addition to abnormalities of other ectodermal organs. Tooth agenesis was more severe in XLHED subjects than in NSH subjects, and there were statistically significant differences in 10 tooth positions in the XLHED and NSH subjects, including canines, premolars, and molars. With the exception of one splicing mutation, all mutations in the NSH subjects were missense mutations, and these were most likely to be located in the tumor necrosis factor (TNF) domain. Further, more than half of the mutations in the XLHED subjects were speculated to be loss of function mutations, such as nonsense, insertion, and deletion mutations, and these mutations were distributed across all EDA domains. Our results show that there exists a correlation between the phenotypes and genotypes of XLHED and NSH subjects harboring EDA mutations. Further, our findings suggest that NSH is probably a variable expression of XLHED. This finding might be useful for clinical diagnosis and genetic counseling in clinical practice, and provides some insight into the different manifestations of EDA mutations in different ectodermal organs.     

唐氏综合征表型与基因的相关性

唐氏综合征(Down’s syndrome,DS)是由于21号染色体的配子减数分裂异常造成的,并且会出现异常的表型,例如,认知损害、学习和记忆能力降低、智力低下、先天性心脏病、早发的阿尔茨海默病以及白血病等.DS个体之间会出现表型的差异,即并不是每个DS患者都会出现所有表型,以及每种表型的严重程度在DS患者之间也是有差异的,这种差异可能与环境、遗传因素有关.因此明确表型和基因的相关性对于致病基因的定位及以后的基因治疗都有着非常重要的意义.现对DS患者以及动物模型的表型和基因相关性研究的进展进行综述.