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71.
9株YONBAN相关TTV变异株全基因序列测定及其结构、分型的研究 总被引:1,自引:2,他引:1
目的:对9个TTV新分离株全基因序列测定,基因结构及基因分型的研究。方法:从9名TTV第4基因群感染阳性的婴儿血清中抽提取其DNA,用long inverted PCR扩增出全基因组,克隆和测定全基因组序列,并对测序结果进行计算机分析。结果:首次次测定了TTV第4基因群共9个新分离株的全基因序列,其中8个分离株代表核基因群首次报道的8个新基因型。结论:TTV基因组核酸序列具有高度异质性及基因型的高度多样性,但是,其独特的转录特性和基因组的基本结构在各自的基因群及基因型中十分保守。 相似文献
72.
Thomas W. Prior Gail D. Wenger Audrey C. Papp Pamela J. Snyder Mary S. Sedra Claire Bartolo Jay W. Moore W. Edward Highsmith 《Human mutation》1995,5(3):263-268
A new strategy has been developed for rapid haplotype analysis based on an initial multiplex amplification of several polymorphic sites, followed by heteroduplex detection. Heteroduplexes formed between two different alleles are detected because they migrate differently than the corresponding homoduplexes in Hydrolink-MDE gel. This simple, rapid method does not depend on specific sequences such as restriction enzyme sites or CA boxes and does not require the use of isotope. This approach has been tested using commonly occurring polymorphisms spanning the dystrophin gene as a model. We describe the use of the method to assign the carrier status of females in Duchenne muscular dystrophy (DMD) pedigrees. The method may be used for other genetic diseases when mutations are unknown or there are few dinucleotide markers in the gene proximity, and for the identification of haplotype backgrounds of mutant alleles. © 1995 Wiley-Liss, Inc. 相似文献
73.
Nisselle AE Delatycki MB Collins V Metcalfe S Aitken MA du Sart D Halliday J Macciocca I Wakefield A Hill V Gason A Warner B Calabro V Williamson R Allen KJ 《Clinical genetics》2004,65(5):358-367
There is debate as to whether community genetic screening for the mutation(s) causing hereditary hemochromatosis (HH) should be implemented, due to issues including disease penetrance, health economic outcomes, and concerns about community acceptance. Hemochromatosis is a common preventable iron overload disease, due in over 90% of cases to C282Y homozygosity in the HFE gene. We are, therefore, piloting C282Y screening to assess understanding of genetic information and screening acceptability in the workplace setting. In this program, HaemScreen, education was by oral or video presentation in a group setting. C282Y status was assessed by polymerase chain reaction (PCR) and melt-curve analysis on DNA obtained by cheek-brush sampling. Of eligible participants, 5.8% (1.5-15.8%) attended information and screening sessions, of whom 97.7% (5571 individuals) chose to be tested. Twenty-two C282Y (1 : 253) homozygotes were identified and offered clinical follow-up. There were 638 heterozygotes (1 : 8.7). The determinants for participation have been analyzed in terms of the principles outlined in the Health Belief Model. Widespread screening for HH is readily accepted in a workplace setting, and a one-to-many education program is effective. The level of participation varies greatly and the advertizing and session logistics should be adapted to the specific features of each workplace. 相似文献
74.
目的 寻找由DNA损伤引起的人类表型缺陷,为人类遗传资源的收集与保藏以及人类基因结构与功能的研究打下基础。方法 通过实地调查得到表型缺陷家系,然后进行系谱分析。结果 得到一个遗传性智力迟缓家系,3代11位成员中有2例患者。结论 遗传性智力迟缓是由DNA损伤引起的人类表型缺陷;该病症符合X-连锁隐性遗传。 相似文献
75.
为解决经颅磁刺激的兴奋点定位问题提出了以圆环面聚焦线圈阵列实现电磁聚焦的方案。而后,使用经过改进的自适应遗传算法对注入阵列各单元线圈电流的大小和相位进行了优化,在目标区域内很好的实现了电磁聚焦。通过计算,显示了线圈阵列在优化后的电流组态下产生的磁场和电场在计算区域内的分布和二维等高线图,表明了该聚焦线圈阵列可在目标区域产生具有良好聚焦性能的电场和磁场分布,并具有可同时聚焦至多个目标的能力。 相似文献
76.
Gene polymorphisms and serological markers of patients with active Crohn's disease in a clinical trial of antisense to ICAM-1
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Yacyshyn BR Schievella A Sewell KL Tami JA 《Clinical and experimental immunology》2005,141(1):141-147
Serological profiles for anti-Saccharomyces cerevisiae antibodies (ASCA)/ perinuclear antineutrophil cytoplasmic antibodies (pANCA) and gene polymorphisms in tumour necrosis factor (TNF)-alpha and intercellular adhesion molecule-1 (ICAM-1) are associated with occurrence and/or outcome in Crohn's disease. The aim of the study was to characterize the ASCA/pANCA profile, soluble ICAM-1 expression and single nucleotide gene polymorphisms (SNPs) in TNF-alpha and ICAM-1 genes. Crohn's patients with moderate disease activity were enrolled in a clinical trial of Alicaforsen (ISIS 2302). Peripheral blood samples were collected prospectively for serum studies and for potential analysis of gene polymorphisms. A multivariate analysis was performed to compare treatment effect with the biomarkers studied. Serological testing for ASCA/pANCA was obtained for 257 patients at baseline: 37% were ASCA(+)/pANCA(-) (Crohn's pattern), 9% had both markers, 15% were ASCA(-)/pANCA(+) and 39% had neither marker. When the data were analysed by multiple regression analysis, a trend was found within the Alicaforsen-treated groups for greater rates of remission in the ASCA(+)/pANCA(-) subgroup versus all other serological profiles (25 versus 14%, P = 0.068), but not versus the placebo remission rate (18.8%). Gene polymorphisms were assessed in 64 patients, 21 from the placebo group. ICAM-1 assessment revealed no over-representation. However, three unique TNF-alpha SNPs were identified that correlated significantly with remission; sites 290 (P = 0.0253), -2735 (P = 0.0317) and -3090 (P = 0.0067). Although the overall clinical trial was negative, we have identified a trend towards clinical remission with Alicaforsen therapy in a subgroup of patients with Crohn's disease expressing ASCA(+)/pANCA(-). Furthermore, we have identified three TNF-alpha SNPs that may also predict a positive therapeutic outcome. 相似文献
77.
目的从基因水平调查了中国华南、华北地区人群HLA-DQB1等位基因频率,并研究比较两地区人群HLA-DQB1多态性分布。方法采用深圳益生堂生物企业有限公司研制开发的“HLA-DQB1低分辨率分型基因芯片检测试剂盒”,应用聚合酶链反应.序列特异性引物+序列特异性寡核苷酸探针芯片检测技术,对700名南方地区的中国人和320名北方地区的中国人进行基因分型。结果鉴定了10个HLA-DQB1等位基因,获得了一组准确、科学的统计数据。结论得到了中国华南、华北地区人群HLA-DQB1等位基因频率差异的数据,证明中国人群HLA-DQB1*02,05,0601,0602,0603的分布南北差异有统计学意义(P〈0.05),为疾病相关性研究、人文科学研究提供了可靠的遗传学数据。 相似文献
78.
Jo EK Kumaki S Wei D Tsuchiya S Kanegane H Song CH Noh HY Kim YO Kim SY Chung HY Kim YH Kook H 《Journal of Korean medical science》2004,19(1):123-126
X-linked severe combined immunodeficiency (X-SCID) is a rare, life-threatening immune disorder, caused by mutations in the gamma c chain gene, which encodes an essential component of the cytokine receptors for interleukin-2 (IL-2), IL-4, IL-7, IL-9, IL-15, and IL-21. A 13-month-old boy with recurrent infections who had reduced serum immunoglobulin levels and decreased numbers of CD3, CD16/56 cells was evaluated for gamma c chain gene mutation and protein expression. The patient had a C-to-T point mutation at nucleotide position 690, one of the hot spots, resulting in a single amino acid substitution of cysteine for arginine (R226C), as determined by direct sequencing and PCR-RFLP. The patient's mother was a heterozygous carrier. Percutaneous umbilical cord blood sampling was performed at the 6-month of gestation in a subsequent pregnancy. As the immunophenotype of the fetus showed an identical pattern, the pregnancy was terminated and genetic analysis of the abortus confirmed recurrence. This is the first report of the molecular diagnosis of X-SCID in Korea. Genetic analysis of the gamma c chain gene is useful for definite diagnosis and genetic counseling for X-SCID. 相似文献
79.
Summary The phenotypic trait starry colony in Saccharomyces is associated with a high spontaneous rho
–
petite mutability. Genetic analysis of this trait has shown the high rho
– mutability to be caused by several modifying genes present together in the strains studied. Every single modifying gene produces only a relatively small enhancement of the rho
– mutability. 相似文献
80.
Heritability and Expression of C-Reactive Protein in Type 2 Diabetes in the Diabetes Heart Study 总被引:1,自引:0,他引:1
Leslie A. Lange Kathryn Burdon † Carl D. Langefeld Yongmei Liu Stephanie R. Beck Stephen S. Rich Barry I. Freedman K. Bridget Brosnihan David M. Herrington Lynne E. Wagenknecht Donald W. Bowden 《Annals of human genetics》2006,70(6):717-725
Elevated C-reactive protein (CRP) levels are associated with both prevalent and incident cardiovascular disease. In this study, familial aggregation was estimated, and we tested for association between serum CRP levels and polymorphisms within the CRP and APOE genes in sib-ships with type 2 diabetes mellitus, a population at increased risk for cardiovascular disease. CRP levels were determined in 461 diabetes-affected subjects from 224 sibships from the Diabetes Heart Study (DHS). Heritability estimates of CRP levels were obtained using variance component models. Genetic influence on serum CRP levels by single nucleotide polymorphisms (SNPs) in the CRP and APOE genes was evaluated by association analysis using mixed models. Subjects were Caucasian American (84%) and African-American (16%), 53% female, and had an average age of 62.2 ± 9.2 years. The median CRP level was 3.3 mg/L (range 0 to 59.3 mg/L), and estimated heritability for CRP was approximately 40%. Estimates of heritability were significantly greater than zero (P < 0.0001) and relatively constant, despite adjustments for important modifiers (age, sex, ethnicity, diabetes duration, statin-use and anti-inflammatory use) of CRP. There was no significant evidence for association of CRP levels with CRP gene SNPs; however, consistent with previous reports, there was significant evidence of association of CRP levels with polymorphisms within the APOE gene. These data indicate CRP levels are significantly influenced by genetic (and/or environmental) factors that are shared within DHS families. While the APOE locus shows evidence of contributing to CRP levels, no evidence of CRP gene polymorphism association with CRP levels was observed. 相似文献