Dravet综合征患者电压依赖性钠通道α1亚基基因5'-非翻译区外显子的遗传变异

目的 筛查Dravet综合征患者的电压依赖性钠通道α1亚基(voltage-gated sodium channel α1-subunit,SCN1A)基因5'-非翻译区外显子突变位点,分析并预测其致病易患性.方法 收集24例Dravet综合征患者的外周血,抽提基因组DNA,采用直接测序法进行SCN1A基因5'-非翻译区外显子突变位点的筛查;用生物信息学方法分析SCN1A基因5'-非翻译区外显子变异位点邻近序列的保守性及潜在的转录因子结合元件,推测其致病易患性.结果 发现位于外显子h2u上的突变位点166.642.520G>A,先证者1为新生突变,而先证者2的突变来自临床表型正常的母亲,该突变位点在100名健康对照者中均未发现.突变位点在哺乳动物中呈中度保守(62.5%),人与其他哺乳动物之间在突变位点邻近序列的平均同源率高达88.5%;166.642.520野生型位点的序列上预测得到一种转录因子结合元件,而突变型位点的序列上预测得到两种转录因子结合元件.结论 突变位点166.642.520G>A与Dravet综合征存在一定程度的相关性,其致病机制有待于进一步实验证实.     

青少年特发性脊柱侧凸疾病候选基因SH3GL1外显子序列比对分析研究

目的 确定SH3GL1是否为青少年特发性脊柱侧凸(AIS)致病基因.方法 对2007年11月至2008年12月收治的56例AIS患者进行研究.其中男性15例,女性41例;年龄8～22岁,平均15岁;侧凸Cobb角25°～110°,平均67.5°.采取以家系为基础的"病例.同胞对照,病例-亲属对照"研究方案,根据AIS候选基因SH3GL1核酸序列,以10个外显子为重点设计引物对,进行PCR扩增、克隆和测序,用Vector NTI Advance 10.3进行序列对比分析,确定碱基突变的有无,并进行蛋白质结构预测分析.结果 共发现12处碱基变异,分别位于第2(3处)、4(1处)、5(4处)、6(1处)、8(1处)和10(2处,非编码区)6个外显子上.其中先证者mRNA第515位碱基如果为T,则形成终止密码子,导致蛋白阅读框发生改变,蛋白质序列预测分析显示编码截短蛋白,从而影响蛋白质的结构.结论 SH3GL1可能是AJS的致病基因之一.     

Exon 11 mutations, Ki67, and p16(INK4A) as predictors of prognosis in patients with GIST

Prognostic biomarkers for GIST are under investigation. The aim of this study was to assess whether exon 11 mutations, Ki67, and p16^INK4A are predictors of prognosis in GIST. Consecutive GIST cases (n = 84) had their specimens evaluated for exon 11 mutations and expression of Ki67 and p16^INK4A. Surgical cases were categorized according to NIH and Miettinen's classification, and survival was analyzed from hospital database. GISTs were predominately gastric (45%) and with spindle cell morphology (74%). The risk category was very low or low in 28%, intermediate in 23%, and high in 49%. Exon 11 mutation was identified in 29 (48%) out of 60 cases studied. There were 12 point mutations, 10 deletions, 4 duplications, and 3 double mutations. A third of GISTs had either high Ki67 index (>3%) or negativity for p16^INK4A. In multivariate analysis, independent predictors of mortality were Ki67 > 3% (HR = 7.3; P = 0.036) and high mitotic index (HR = 10.4; P = 0.043). There was no association between exon 11 mutations and survival. This study suggests that Ki67 > 3% is an independent predictor of poor prognosis in patients with GIST. Exon 11 mutations and negativity for p16^INK4A need further studies to address the prognostic value.     

苯丙酮尿症患儿苯丙氨酸羟化酶exon6基因、exon7基因突变的研究

目的 探讨山西省苯丙酮尿症(PKU)患儿的苯丙氨酸羟化酶(PAH)exon6 基因、exon7 基因的突变特征.方法 通过测序及序列比对的方法对56 例PKU 患儿和112 例健康儿童的336 个PAH exon6 基因、exon7 基因进行序列分析,以确定其突变位点、性质和频率.结果 通过序列分析,发现在PKU 患儿和健康儿童中均高频率的出现Q232Q(CAA→CAG)、V245V(GTG→GTA)两种同义突变,其中cDNA 696 位点的频率高达96.2%,cDNA 735 位点的频率高达76.1%.健康儿童的其他序列与Genbank 完全相同.而PKU 患儿的基因序列中还发现了9 种共计37 个突变基因,占全部PAH 突变基因的33.04%.exon 6 仅发现一种突变基因Y204C,突变频率达9.8%;exon 7 中R243Q 的突变率最高,占10.7%,其次为Ivs7 +2 T ＞A,占5.4%,其余的G247V、R252Q、L255S、R261Q、T278I 和E280K 分别占0.9%、0.9%、0.9%、0.9%、2.7%和0.9%.9 种突变都在之前文献中有过报道,其中有7 种错义突变和2 种剪接位点突变.结论 明确了PAH exon6 基因、exon7 基因的突变种类和分布等特征,表明exon6 基因、exon7 基因中Y204C 和R243Q属于山西人群中PAH 基因突变的热点.     

肯尼迪病一家系临床特点及分子遗传学研究

目的:报道一经基因诊断的肯尼迪病家系,探讨其临床特征和分子机制.方法:收集肯尼迪病患者家系的临床资料,用基因分析的方法,明确家系先证者雄激素受体(AR)基因第1号外显子CAG序列的重复数.结果:该家系有4例患者,临床特征为男性成年期发病,进行性四肢近端肌肉无力、萎缩,可伴乳房女性化、性功能减退,先证者经AR基因检测CAG重复数为51次,肌电图显示感觉、运动神经均受累,血清甘油三酯增高.结论:雄激素受体基因检测是诊断该病最可靠的方法,对怀疑为肯尼迪病的患者均应进行基因诊断.     

HLA-G单核苷酸多态性与重度子痫前期的关联研究

目的:检测人类白细胞抗原(human leukocyte antigen,HLA)-G单核苷酸多态性(SNPs)位点在重度子痫前期患者及正常孕妇中的分布,了解重度子痫前期患者HLA-G SNPs的变化,以期进一步明确HLA-G在子痫前期免疫发病机制中的作用。方法:收集重度子痫前期组67例和对照组37例血液样本,提取基因组DNA,选取HLA-G外显子(Exon)2、3为实验研究区域,合成荧光标记引物,聚合酶链反应(PCR)、测序进行片段序列SNPs分析。统计分析所测SNPs位点与重度子痫前期的关联程度。结果:在HLA-G Exon2发现2个SNPs,为C374T及G476A;Exon3发现3个SNPs,为C810T、C859A及G954A。HLA-G Exon2、3 SNPs在重度子痫前期组及正常孕妇组间的分布差异无统计学意义(均P>0.05)。结论:(1)在HLA-G Exon2、3共发现5个SNPs位点,均为同义突变,与重度子痫前期无相关性。(2)C374T和G954A为新发现的HLA-G SNPs,向db SNP提交后获得NCBI Assay Id(ss#)119994701和119994702,Reference SNP Id(rs#):rs77474325和rs75783850。     

内皮型一氧化氮合酶基因G894T变异与超重和高血压的关系

目的 探讨内皮型一氧化氮合酶(eNOS)基因第7外显子G894T变异与超重在高血压患病中的意义。方法 在人群中筛检出未经药物系统治疗的116例高血压患者及136名血压正常者为研究对象;运用PCR-限制性片段长度多态性检测G894T变异;用相加模型分析G894T变异与超重之间的交互作用;用人群归因危险度百分比(PAR％)反映人群中的病因分值。结果 G894T变异与超重对高血压患病具有正交互作用;归因交互效应为1．99;归因交互效应百分比为30．76％;纯因子间归因交互效应百分比为36．38％。用多元logistic回归分析调整年龄、性别、吸烟指数及饮酒指数后,G894T变异与超重对高血压患病仍具有正交互作用。调整上述混杂因素后,归因交互效应为2．85;归因交互效应百分比为39．97％;纯因子间归因交互效应百分比为46．49％。在给定条件下计算的PAR％约为15％。结论 eNOS基因第7外显子G894T变异与超重之间的交互作用在该研究人群高血压患病中具有重要意义;在仅仅对具有G894T。变异与超重同时存在的部分人群中控制超重可明显降低一般人群高血压的患病率。     

Mutations in c-kit Gene Exons 9 and 13 in Gastrointestinal Stromal Tumors among Japanese

Gain-of-function mutation in c-kit proto-oncogene exon 11 has been described in about 20-50% of gastrointestinal stroma tumor (GIST). Recently, additional mutational hot-spots in exon 9 and exon 13 of the c-kit gene have been reported in GISTs without mutations of exon 11, but a subsequent report in a Western population indicated that only a small portion of GISTs (eight of 200 GISTs, 4%) showed mutations in these regions. In this study, we evaluated mutations in exon 9 and exon 13 of the c-kit gene by both polymerase chain reaction-single strand conformation polymorphism analysis and direct sequencing in 48 GISTs in a Japanese population, for which the clinicopatho-logical and immunohistochemical features and mutations in exon 11 had previously been reported. C-kit gene mutation in exon 9, representing insertion of GCC TAT, was identified in only 4 of 48 GISTs (8%), and none of the GISTs had mutations in exon 13. All four GISTs with mutation in exon 9 were high-risk, and the patients died of multiple tumor metastasis. Mutations in exon 9 and exon 13 of the c-kit gene were also rare events in Japanese GISTs and were related to a poor prognosis. These results in Japanese are consistent with those in Western populations, although a preferential occurrence of GISTs with exon 9 mutation in the small intestine, which was suggested in a previous report, was not observed.