大肠癌组织p53基因突变及其与临床病理关系的探讨

应用非同位素标记ＰＣＲ－ＳＳＣＰ技术对３４例大肠癌组织ｐ５３基因第五外显子突变进行了检测。结果：５０％（１１／２２）结肠癌，８．３％（１／１２）直肠癌存在ｐ５３基因突变，低分化腺癌高于高、中分化腺癌（Ｐ＜０．０５），ＤｕｋｅｓＢ、Ｃ期高于ＤｕｋｅｓＡ期（Ｐ＜０．０５），ｐ５３基因第五外显子突变在已发生淋巴转移的大肠癌组织中呈现较强的趋势。提示：检测结肠癌原发灶ｐ５３基因第五外显子突变，对指导结肠癌的诊断、治疗及预后判断具有一定意义     

Multiplex PCR analysis of in vivo-arising deletion mutations in the hprt gene of human T-lymphocytes

A multiplex polymerase chain reaction (PCR) procedure was adapted for the rapid and efficient evaluation of deletions of the hypoxanthine guanine phosphoribosyltransferase (hprt) gene in human T-lymphocytes. The hprt clonal assay was used to isolate in vivo-arising hprt-deficient T-cells from six healthy males. Mutant frequencies ranged from 9-27 × 10^?6. Simple crude cellular extracts from 223 mutants were analyzed for hprt gene deletion. Sixteen (7.2%) were found to be due to total gene deletion and 22 (9.9%) were due to partial gene deletion. The relatively high frequency of total gene deletions was caused by replicate isolates of a single mutational event as shown by single-strand conformation polymorphism (SSCP) analysis of rearranged T-cell receptor (TCR)-γ genes. Eighteen of the 22 partial hprt gene deletion mutants were determined to be of independent origin based on a unique hprt mutation or SSCP-TCR-γ pattern. One-half (9/18) of the partial deletion mutants involved all or part of exon 4 alone, suggesting that this region of the hprt gene is prone to deletion. The small deletions effecting exon 1 (1 mutant), exon 2 (2 mutants), and exon 4 (6 mutants) would not have been detected by conventional Southern blot analysis and may represent a new, previously unrecognized class of mutations. The ready isolation of such intragenic deletions will allow the characterization of breakpoint junctions and may provide insights into the important processes of DNA breakage and rejoining. © 1994 Wiley-Liss, Inc.     

重庆市新生儿高胆红素血症患儿G6PD基因突变类型及临床特点

目的研究重庆市新生儿黄疸儿G6PD三种常见基因突变与其临床表现特点之间的关系。初步估计其基因突变频率并探讨其临床意义和遗传学特征。方法应用突变特异性扩增系统(ARMS)法,检测54例重庆市新生儿黄疸儿的G6PD基因突变类型。结果检出G1388A突变39例(72%),G1376T突变8例(15%),未定型者7例(13%)。未检出G95A。结论本研究首次对重庆市新生儿黄疸儿进行G1388A、G1376T和A95G突变检测。提示G1388A和G1376T为重庆市新生儿黄疸儿G6PD缺乏症基因突变的主要类型。ARMS法是一种简便、快速、经济的检测G6PD已知基因突变的方法。本研究发现这两种突变类型仅见于中国人和华裔人群,具有遗传学及临床意义。     

Smith-Fineman-Myers综合征的候选基因GPC4分析

目的:探讨GPC4基因与中国山东Smith-Fineman-Myers综合征(SFMS)的关系,并分析SFMS患者GPC4基因突变。方法:利用primer3设计扩增GPC4全部编码序列及内含子和外显子接头序列的引物,采用PCR扩增结合PCR产物直接测序方法检测GPC4基因开放性阅读框架区域基因突变。结果:在GPC4基因开放性阅读框架区域内并未检测到导致疾病的基因突变。结论:山东SFMS家系患者不是由于GPC4基因编码区域基因突变所致。     

A clinical and genetic study of 56 Saudi Wilson disease patients: identification of Saudi-specific mutations

Wilson disease (WD) is a hereditary disorder, with recessive transmission and genetic heterogeneity. Several mutations of ATP7B, the gene underlying WD, were reported in many ethnic groups. In this study, mutation screening in ATP7B of 56 Saudi Arabian WD patients was undertaken. The clinical data of all patients were recorded. The entire ATP7B coding sequence, including intron-exon boundaries were screened for mutation by the polymerase chain reaction (PCR)-based mutation detection technique and DNA sequencing. Thirty-nine patients were symptomatic at presentation and 17 subjects were pre-symptomatic siblings of affected patients. Fourteen patients had neurological, 11 patients had mixed (hepatic and neurological), and 14 patients had hepatic presentations. Family history suggestive of WD was present in 72% of cases and 68% had consanguineous parents. Genetic analysis showed disease-causing mutations in three exons (exons 8, 19 and 21) of the ATP7B gene in 28 patients (50%). Mutations in exons 21 (18 cases) and 19 (one case) were unique for Saudis. This large series of Saudi patients with WD has shown wide variability in the genomic substrate of WD. There is no correlation between genotype and clinical presentation.     

荧光偏振检测HBV DNA C区BCP双突变

目的：建立简便、灵敏的HBV DNA序列中BCP双突变点的检测方法．方法：采用终点终止法和偏振光检测技术进行点突变的检测．首先对HBV C区基因进行PCR扩增，然后用特异探针与扩增产物中待测核苷酸的下游序列杂交，使探针的3’端可以在DNA聚合酶的催化下，依据其互补链上的待测核苷酸连接上一个标有特定荧光素的ddNTP，然后检测该3’端带有荧光素的探针，根据检测到的荧光素种类和偏振光的强度可以判定待测点是何种核苷酸．结果：该方法可以检测出HBV基因序列中BCP双突变核苷酸类型以及检测1个拷贝的模板，并且可以从BCP野性株DNA序列中检出5％BCP双突变DNA序列．结论：该技术可以检测血清中HBV DNA C区BCP双突变．     

胰腺癌组织中BRAF表达的初步研究

目的:了解BRAF基因在正常胰腺和胰腺癌组织中的表达水平。方法:6例胰腺癌标本取自胰腺癌手术患者,3例正常胰腺组织取自外伤性胰腺损伤需切除部分胰腺者。用Trizol法抽提每份组织的总RNA,分别进行紫外分光光度计测定、琼脂糖凝胶电泳及Lab on ch ip检测,对总RNA进行质控;应用实时定量PCR技术检测正常胰腺和胰腺癌组织BRAF的mRNA水平;应用W estern b lot检测BRAF的蛋白表达水平。结果:BRAF mRNA水平在正常胰腺组织中为0.001 016 7±0.000 25,胰腺癌组织中为0.002 606 2±0.001 09,上调2.56倍;W estern b lot显示,正常胰腺组织BRAF蛋白表达为6.70±2.50,胰腺癌组织为21.23±5.60,上调3.17倍。结论:胰腺癌组织中BRAF mRNA和蛋白表达水平均明显上调,其可能的调控机制及生物学效应还有待进一步研究。     

G2019S LRRK2 mutation in familial and sporadic Parkinson's disease in Russia.

Among mutations associated with autosomal dominant and sporadic Parkinson's disease (PD) the G2019S substitution in the leucine-rich repeat kinase 2 (LRRK2) gene is the most frequently identified. To estimate its frequency in Russia, we analyzed 208 patients with PD from the Northwestern region of Russia. Of these, 51 patients were probands from families with PD compatible with autosomal dominant inheritance. The control group represented 161 subjects without neurological disorders settled in the same region. The frequency of the G2019S mutation was greater in familial PD (2 [3.9%] of 51) than in sporadic PD (1 [0.6%] of 157). In addition, this mutation was found in the proband's father, who also had PD, in 1 PD family, and in 1 carrier without signs of PD at age 40 in another PD family. All carriers were heterozygous for the G2019S mutation and reported the Ashkenazi Jewish origin. The mutation was not found in the control group.     

遗传性痉挛性截瘫paraplegin基因的突变分析

目的探讨paraplegin基因在中国人遗传性痉挛性截瘫(HSP或SPG)中的突变特点,为该病的基因诊断奠定基础。方法应用聚合酶链反应单链构象多态性(PCRSSCP)结合DNA序列分析方法,对来自全国8个常染色体隐性遗传HSP家系的先证者和14例散发性HSP患者进行paraplegin基因突变分析。结果所有外显子均可扩出,发现15号外显子上2例先证者出现异常SSCP条带,经DNA序列分析发现2063及2066位点上存在碱基G被A替换,但家系内不存在共分离的现象,且正常对照者也存在G被A替换,考虑为多态,其中G2066A为首次发现。结论Paraplegin基因突变可能在中国人HSP患者中少见。2063G→A及2066G→A是paraplegin基因的两个多态性改变,其中2066G→A为首次发现。     

人心肌肌钙蛋白I第2和第4个密码子同义突变对其在大肠埃希菌中表达的影响

目的 对人心肌肌钙蛋白I（cTnI）基因实行定点突变并进行原核表达，观察此突变对cTnI表达量的影响。方法 利用RT-PCR方法从人心肌细胞的总RNA中克隆出编码人心肌肌钙蛋白I的cDNA片段，设计引物将其第2和第4个密码子突变后插入原核表达载体形成重组体，并导人宿主菌BL21（DE3）中，经IPTG诱导表达，Ni-NTA树脂纯化后行Western blot鉴定，观察突变对cTnI表达的影响。结果 突变后的cTnI基因与对照组相比在大肠埃希菌中得到高效表达，经纯化可获得电泳单点纯的cTnI蛋白。结论 成功克隆了cTnI基因，所设计的同义突变可促进cTnI在大肠埃希菌中的高效表达。