中国汉族人Brugada综合征患者SCN5A基因Ⅳ区一个新的突变

背景Brugada综合征是一种易导致猝死的具有遗传倾向的疾病，与编码心肌钠通道的基因突变有关。目的研究中国Brugada综合征患者SCN5A基因的碱基改变情况。方法对15例先证者及家系进行直接SCN5A基因测序。DNA来源于患者外周血白细胞。全部28个外显子通过设计的40对引物进行PCR扩增，扩增后的产物直接测序。结果在一个家系上发现了一个错义突变，即G5080A（R1628Q），该突变导致心肌细胞钠通道的α亚基第IV结构域的第4片段发生改变。在150个正常对照者未发现此碱基改变。结论G5080A（R1628Q）可能是中国Brugada综合征患者SCN5A基因新的突变位点。     

中国汉族人Brugada综合征患者SON5A基因Ⅳ区一个新的突变

背景 Brugada综合征是一种易导致猝死的具有遗传倾向的疾病,与编码心肌钠通道的基因突变有关.目的 研究中国Brugada综合征患者SCN5A基因的碱基改变情况.方法 对15例先证者及家系进行直接SCN5A基因测序.DNA来源于患者外周血白细胞.全部28个外显子通过设计的40对引物进行PCR扩增,扩增后的产物直接测序.结果 在一个家系上发现了一个错义突变,即G5080A(R1628Q),该突变导致心肌细胞钠通道的α亚基第Ⅳ结构域的第4片段发生改变.在150个正常对照者未发现此碱基改变.结论 G5080A(R1628Q)可能是中国Brugada综合征患者SCN5A基因新的突变位点.     

中国汉族人Brugada综合征患者SCN5A基因Ⅳ区一个新的突变

背景 Brugada 综合征是一种易导致猝死的具有遗传倾向的疾病,与编码心肌钠通道的基因突变有关。目的研究中国 Brulgada 综合征患者 SCN5A 基因的碱基改变情况。方法对15例先证者及家系进行直接SCN5A 基因测序。DNA 来源于患者外周血白细胞。全部28个外显子通过设计的40对引物进行 PCR 扩增,扩增后的产物直接测序。结果在一个家系上发现了一个错义突变,即 G5080A(R1628Q),该突变导致心肌细胞钠通道的α亚基第Ⅳ结构域的第4片段发生改变。在150个正常对照者未发现此碱基改变。结论 G5080A(R1628Q)可能是中国 Brugada 综合征患者 SCN5A 基因新的突变位点。     

Brugada综合征相关基因SCN5A新突变位点的检测

目的 研究中国人Brugada综合征相关基因SCN5A突变情况。方法 利用多聚酶链反应及DNA测序对1个Brugada综合征家系SCN5A基因的全部28个外显子进行基因检测。结果 在国内外已知突变点均无突变，发现1个新的错义突变位点(A5471G)，其相应的氨基酸改变为N1774S。结论 在中国人Brugada综合征患者的SCN5A基因上发现1个新的突变位点。     

一个中国大家系Brugada综合征相关基因SCN5A的突变位点检测

目的：研究一个中国大家系Brugada综合征相关基因SCN5A的突变情况。方法：收集一个Brugada家系（43例）的临床资料，采用聚合酶链反应及直接测序法对此家系进行SCN5A基因突变检测，同时对136名家系外健康对照者的该位点进行单链构象多态性（SSCP）分析。结果：在Brugada家系中发现了一个杂合变异，即SCN5A基因第12外显子上发现一个错义变异（A1685G），导致代表组氨酸的558位密码子突变为精氨酸（H558R）。结论：在中国人Brugada综合征患者的SCN5A基因上发现了一个已经报道的错义多态位点（H558R）。     

中国一家系Brugada综合征相关基因SCN5A突变位点的检测

目的研究一个中国家系Brugada综合征相关基因SCNSA的突变情况。方法收集一个Brugada家系的临床资料,采用聚合酶链反应及直接测序法对该家系进行SCN5A基因突变检测,同时对136例家系外健康对照者的该位点进行单链构象多态性分析。结果在Brugada家系中发现了两个杂合变异,即SCN5A基因第二外显子上发现一个同义变异（A129G）,没有导致氨基酸的改变（A29A）;第26外显子发现一个错义变异（T4492A）,导致代表酪氨酸的1494位密码子突变为天门冬酰胺（Y1494N）。结论在中国人Brugada综合征患者的SCNSA基因上发现了一个已经报道的同义多态位点（A29A）及一个新的错义突变位点（Y1494N）。     

中国人Brugada综合征分子遗传学研究发现一个新的SCN5A基因突变

目的 研究探索中国人Brugada综合征是否存在基因突变及突变类型。并分析突变可能的致病机制。方法 以SCN5A作为候选基因。应用PCR-SSCP技术对4例患及其家系成员进行突变检测，并用DNA直接测序验证。结果 SSCP分析在一个家系内发现SCN5A基因第8外显子PCR产物出现异常带型，而在200例正常对照中均未发现此改变，DNA直接测序显示SCN5A编码区第317位密码子的第三位碱基G→C的错义突变，并导致位于DⅠS5与DⅠS6节段之间与钠通道蛋白“孔”区相关的第一个P-Loop结构上一个赖氨酸（K）被天冬酰胺（N）取代（K317N）。一个家系调查表明，21例家系成员中共有10例携带，其中有症状（4例）均为携带，2例无症状携带有心电图改变，隐性携带占40%，结论 在中国人中发现了Brugada综合征一个新的SCN5A基因突变。     

中国散发Brugada综合征患者SCN5A基因突变位点的检测

目的 对5例中国散发Brugada综合征患者进行SCN5A基因突变位点检测.方法 采用直接测序法对5例散发Brugada综合征患者进行SCN5A基因碱基突变位点的检测,测序结果用Chromas软件进行BLAST分析,再将测序峰与网上检索结果重新比对.结果 1例Brugada患者发现了一个同义杂合变异,即SCN5A基因第20外显子上发现一个碱基变异（C3549T）,其所编码的第1 183位苏氨酸没有发生改变（T1183T）.结论 在中国散发Brugada综合征患者的SCN5A基因上发现了1个新的碱基杂合同义突变.     

Brugada综合征一家系中2例患者的SCN5A基因突变及意义

目的 观察Brugada综合征一家系中2例患者的SCN5A基因突变情况,并探讨其意义.方法 选择Brugada综合征一家系2例患者,采用直接测序法对其SCN5A基因突变进行检测.结果 该家系中发现1个纯合变异,即SCN5A基因第28外显子上的同义变异（C5457T）,其所编码的1819位天冬氨酸密码子没有发生改变.结论 该Brugada综合征家系2例患者的SCN5A基因上存在1个同义变异,但SCN5A基因不是患者的致病基因.     

七例Brugada综合征患者SCN5A基因突变检测

目的 对7例Brugada综合征患者进行SCN5A基因突变检测,分析其分子遗传学特征. 方法 提取7例Brugada综合征患者外周血DNA样本,设计41对引物进行多聚核苷酸聚合酶链式反应,扩增SCN5A基因28对外显子,并采用双脱氧链终止法进行直接测序. 结果 SCN5A基因外显子部分未发现新的突变位点. 结论 Brugada综合征可能存在除SCN5A基因之外的其他相关基因突变.     

Brugada综合征SCN5A基因的三个新突变

目的 研究Brugada综合征相关基因SCN5A突变情况。方法 以4例Brugada综合征患者和9例临床可疑Brugada综合征患者为研究对象,采用聚合酶链反应和双脱氧末端终止测序法对所有患者进行SCNSA基因扫描。对阳性结果者进行家系中其他成员的筛查。结果 在1个Brugada综合征家系发现两个杂合突变,即SCN5A基因第3外显子上发现一错义突变（G283A）,导致代表缬氨酸残基的第95位密码子突变为异亮氨酸残基（V95I）,第28外显子上也发现一错义突变（CA946T）,导致代表丙氨酸的第1649位密码子突变为缬氨酸（A1649V）。在1个临床可疑Brugada综合征家系发现一杂合突变,即SCN5A基因第28外显子缺失3个碱基（TCT）,导致代表苯丙氨酸残基的第1617位密码子缺失（delF1617）。结论 在Brugada综合征患者发现了3个SCN5A基因新突变（V95I、A1649V、delF1617）。     

Brugada syndrome with a novel missense mutation in SCN5A gene: A case report from Bangladesh

Brugada syndrome is an inherited cardiac arrhythmia that follows autosomal dominant transmission and can cause sudden death. We report a case of Brugada syndrome in a 55-year-old male patient presented with recurrent palpitation, atypical chest pain and presyncope. ECG changes were consistent with type 1 Brugada. Gene analysis revealed a novel missense mutation in SCN5A gene with a genetic variation of D785N and a nucleotide change at 2353G-A. One of his children also had the same mutation. To our knowledge this is the first genetically proved case of Brugada syndrome in Bangladesh.     

Genetic analysis of Brugada syndrome in Western Japan: two novel mutations.

BACKGROUND: Brugada syndrome is a form of idiopathic ventricular fibrillation characterized by right bundle-branch block pattern and ST elevation in the right precordial leads of the ECG. The SCN5A gene encodes the alpha-subunit of the human heart sodium channel, which plays a critical role in cardiac excitability, and mutations of SCN5A could underlie Brugada syndrome. METHODS AND RESULTS: To detect mutations of SCN5A, DNA samples from 12 Japanese patients with Brugada syndrome were analyzed using direct sequencing. Two patients had novel mutations, G292S and S835L, but no other mutations of SCN5A were detected in the remaining patients. The first mutation, G292S, was identified adjacent to the pore-lining region between the DIS5 and DIS6 transmembrane segments of SCN5A, and the second mutation, S835L, was in the intracellular loop connecting the DIIS4 to DIIS5. Both mutations were not detected in 100 unrelated control subjects. CONCLUSION: Two novel SCN5A mutations have been found in Japanese patients with Brugada syndrome.     

Clinical and electrophysiological characteristics of Brugada syndrome caused by a missense mutation in the S5-pore site of SCN5A

Brugada syndrome is an inherited cardiac disorder caused by mutations in the SCN5A gene encoding the cardiac sodium channel alpha-subunit, and potentially leads to ventricular fibrillation and sudden death. We report a case of a novel SCN5A mutation associated with Brugada syndrome. A 51-year-old man suffered from recurrent nocturnal syncopal attacks due to polymorphic ventricular tachycardia. His electrocardiogram showed ST-segment elevation in V1-V3 leads, but there was no evidence of structural heart disease. DNA sequence analysis of SCN5A in this patient revealed a missense mutation (R282H) in the S5-pore region of domain I. This mutational change was not present in 100 healthy Japanese controls. In the patient's family, a 36-year-old brother had died suddenly. Genetic analysis identified two other carriers of the R282H mutation, who had ST-segment elevation and slightly increased QRS widths, but they experienced no syncopal episodes or ventricular fibrillation. Electrophysiological investigation of the R282H mutant channel expressed in cultured cells showed a severe reduction in sodium current density and a mild positive shift of activation curve. R282H did not enhance intermediate inactivation. Single-channel conductance of R282H was slightly decreased compared with WT. The electrophysiological characteristics of the R282H channel are suggested to be closely related to the clinical phenotype of Brugada syndrome.     

Sodium Channelopathies: Do We Really Understand What's Going On?

Sodium Channelopathies: Do We Really Understand ? Long‐QT syndrome, Brugada syndrome, and conduction disease may be caused by mutations in the cardiac sodium channel gene SCN5A, and from the ECG one can already presume either a gain‐ or a loss‐of‐function defect. We describe a family harboring 2 SCN5A mutations: the ΔKPQ mutation, the “classical” gain‐of‐function mutation associated with Long‐QT syndrome, and the I1660V mutation, a loss‐of‐function mutation associated with Brugada syndrome. However, we were surprised by the result of genetic testing in this family. One son who carried the ΔKPQ mutation but not the I1660V mutation did not show the expected Long‐QT phenotype but, unexpectedly, showed a conduction disease/Brugada phenotype. (J Cardiovasc Electrophysiol, Vol. 22, pp. 590‐593 May 2011)     

Novel brugada SCN5A mutation leading to ST segment elevation in the inferior or the right precordial leads

Mutations in the SCN5A gene can lead to the Brugada syndrome, a genetically inherited form of idiopathic ventricular fibrillation that has a characteristic ECG phenotype usually restricted to precordial leads V1-V3. We identified a novel G752R SCN5A missense mutation leading to various degrees of the Brugada ECG phenotype in members of a French family. In the proband, the G752R mutation produced ST segment elevation and prominent J wave in leads II, III, and aVF. In four other relatives, ST segment elevation in the right precordial but not in the inferior leads was observed either spontaneously or under flecainide challenge. Recombinant G752R mutant exhibited a markedly reduced Na+ current amplitude and a voltage shift in both activation and inactivation curves. The mutant was found in all affected but not in nonaffected family members. One additional gene-carrier had an almost normal ECG (silent gene-carrier). We provide genetic demonstration that Brugada ECG anomalies related to a unique SCN5A mutation can be observed either in the inferior or the right precordial leads.