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排序方式: 共有9865条查询结果,搜索用时 15 毫秒
61.
Hans-Jürgen Rode Joachim Jakob Bugert Michaela Handermann Paul Schnitzler Roland Kehm Waltraud Janssen Hajo Delius Gholamreza Darai 《Virus genes》1994,9(1):61-75
The complete DNA nucleotide sequence of theEcoRI DNA fragment N (0.235 to 0.258 viral map units) of equine herpes virus type 2 (EHV-2) strain T400/3 was determined. This DNA fragment comprises 4237 bp with a base composition of 55.23% G+C and 44.77% A+T. Nineteen open reading frames (ORFs) of 50-287 amino acid (aa) residues were detected. ORF number 10 is located between the nucleotide position 2220 and 2756 coding for a protein of 179 amino acid residues. This protein shows significant homology to the cytokine synthesis inhibitory factor (CSIF; interleukin 10) of human (76.4%) and mouse (68.5%), and to the Epstein-Barr virus (EBV) protein BCRF1 (70.6%). The existence of an interleukin 10 (IL-10) analogous gene within the genome of the EHV-2 was confirmed by screening the genome of nine EHV-2 strains using specific oligonucleotide primers corresponding to the 5 and 3 region of this particular gene by polymerase chain reaction. In all experiments an 870 bp DNA product was amplified. The specifity of the amplified DNA fragments obtained from individual EHV-2 strains was confirmed by DNA-DNA hybridization experiments. The DNA sequence analysis of the amplified DNA products of the EHV-2 strain LK was carried out. This analysis revealed the identity of the corresponding IL-10 gene (540 bp) of this strain to the IL-10 gene of EHV-2 strain T400/3. The presented data indicate that the EHV-2 genome harbors a viral interleukin 10-like gene. This is further evidence that the IL-10 gene can be present in the genomes of members of the Herpesviridae family. 相似文献
62.
A number of HLA alleles have been newly identified. This concerns HLA-A*0310, A*2907, B*4435, Cw*0206, Cw*0506, of which Cw*0206 was found in three unrelated individuals, all B*4002 positive. Some other alleles are also presented but confirm earlier detected sequences: A*3106, Cw*0314, DRB1*0322, and DRB1*1433. Moreover, we identified B*3924 in a bone marrow transplant recipient and in five of six unrelated stem cell donors, selected for this patient. In all cases, B*3924 was found on a haplotype combining A*0201, B*3924, Cw*0701, and DRB1*1303. The observation of this extended haplotype is of importance for the selection for stem cell transplantation. Cells expressing B*3924 and B*4435 were typed by serology as B39 and B44, respectively. Cells expressing HLA-A*0310 do not express A3 but type as A-Blank. 相似文献
63.
Germline mutations in breast cancer susceptibility genes, BRCA1 and BRCA2, are responsible for a substantial proportion of high‐risk breast and breast/ovarian cancer families. To characterize the spectrum of BRCA1 and BRCA2 mutations, we screened Czech families with breast/ovarian cancer using the non‐radioactive protein truncation test, heteroduplex analysis and direct sequencing. In a group of 100 high‐risk breast and breast/ovarian cancer families, four novel frame shift mutations were identified in BRCA1 and BRCA2 genes. In BRCA1, two novel frame shift mutations were identified as 3761‐3762delGA and 2616‐2617ins10; in BRCA2, two novel frame shift mutations were identified as 5073‐5074delCT and 6866delC. Furthermore, a novel missense substitution M18K in BRCA1 gene in a breast/ovarian cancer family was identified which lies adjacent just upstream of the most highly conserved C3HC4 RING zinc finger motif. To examine the tertiary structure of the RING zinc finger domain and possible effects of M18K substitution on its stability, we used threading techniques according to the crystal structure of RAG1 dimerization domain of the DNA‐binding protein. © 2000 Wiley‐Liss, Inc. 相似文献
64.
Alleles encoding HLA-C antigens in Japanese were identified by polymerase chain reaction followed by single strand conformation polymorphism (PCR-SSCP) and nucleotide sequencing analyses. The results showed that at least sixteen different alleles code for eight serologically detectable antigen groups and undetectable blanks. Cwl was mainly encoded by Cw*0102, whereas two split antigens of Cw3, Cw9 and Cw10, were encoded by Cw*0303 and Cw*0304, respectively. Cw4 and Cw6 were encoded by Cw*0401 and Cw*0602, respectively. Seven alleles, Cw*0801, Cw*0803, Cw*1202, Cw*1203, Cw*1402, Cw*1403 and Cw*1502, were found to encode serological HLA-C "blanks" in Japanese. Moreover, errors in the published nucleotide sequences of Cw*0501 and Cw*1201 were corrected. Twenty-one HLA-C alleles were distinguished from each other by means of group-specific PCR amplification followed by the SSCP method developed in the present study. The system using genomic DNAs can be used effectively for identification of new HLA-C alleles. 相似文献
65.
Johanna L. Schmidt MPH MGC CGC Amy Pizzino MS CGC Jessica Nicholl MS CGC Allison Foley MMSc CGC Yue Wang PhD FACMG Jill A. Rosenfeld MS CGC Lindsey Mighion MS CGC Lora Bean PhD Cristina da Silva MS Megan T. Cho MS CGC Rebecca Truty PhD John Garcia PhD Virginia Speare PhD Kirsten Blanco BS Zoe Powis MS CGC Grace M. Hobson PhD Susan Kirwin BS Bryan Krock PhD FACMG Hane Lee PhD Joshua L. Deignan PhD Maggie A. Westemeyer MS CGC Ryan L. Subaran PhD Isabelle Thiffault PhD FABMGG Ellen A. Tsai PhD Terry Fang PhD Guy Helman BS Adeline Vanderver MD 《American journal of medical genetics. Part A》2020,182(8):1906-1912
Leukodystrophies are a heterogeneous group of heritable disorders characterized by abnormal brain white matter signal on magnetic resonance imaging (MRI) and primary involvement of the cellular components of myelin. Previous estimates suggest the incidence of leukodystrophies as a whole to be 1 in 7,000 individuals, however the frequency of specific diagnoses relative to others has not been described. Next generation sequencing approaches offer the opportunity to redefine our understanding of the relative frequency of different leukodystrophies. We assessed the relative frequency of all 30 leukodystrophies (associated with 55 genes) in more than 49,000 exomes. We identified a relatively high frequency of disorders previously thought of as very rare, including Aicardi Goutières Syndrome, TUBB4A‐related leukodystrophy, Peroxisomal biogenesis disorders, POLR3‐related Leukodystrophy, Vanishing White Matter, and Pelizaeus‐Merzbacher Disease. Despite the relative frequency of these conditions, carrier‐screening laboratories regularly test only 20 of the 55 leukodystrophy‐related genes, and do not test at all, or test only one or a few, genes for some of the higher frequency disorders. Relative frequency of leukodystrophies previously considered very rare suggests these disorders may benefit from expanded carrier screening. 相似文献
66.
目的探讨性分化发育不良患者SRY基因的作用及其临床意义.方法选择在我院遗传室咨询的性分化发育不良患者50例,在染色体核型分析的基础上,应用聚合酶链(PCR)技术对每例患者检测SRY基因,应用DNA序列分析技术对6例性染色体XX或XY而SRY( )的女性患者和2例染色体为46,XY、SRY( )睾丸发育不良的男性患者,进行了SRY基因序列分析.结果 (1)1例46,XX女性SRY( ),1例46,XX男性SRY(-),1例46,XX/46,XY女性和1例核型为47,XXY男性SRY( ),在46,XY患者中女性11例,男性6例SRY( ).(2)1例46,XX女性SRY基因存在点突变,1例46,XY女性患者SRY基因序列存在点突变和移码突变.结论对性分化发育不良患者进行SRY检测及其基因分析,不仅有利于为该类患者寻找病因,而且有利于指导治疗. 相似文献
67.
Nesci S Buffi O Iliescu A Luchetti M Battarra MR Amadei M Visani G Andreani M 《Tissue antigens》2004,63(3):282-283
We report here the identification of a novel DRB1*11 allele, DRB1*1144, identified during sequence-based HLA-DRB1 typing. Molecular cloning and direct sequencing confirmed that the new allele is identical to DRB1*110401 at exon 2, except for a single nucleotide substitution (GTG-->GCG) changing codon 38 from Valine to Alanine. 相似文献
68.
An asymptomatic carrier and all six of his family members were detected positive for HBV DNA in their peripheral blood leukocytes (PBL), by polymerase chain reaction. Direct sequencing of the amplified DNA revealed that the HBV DNA from the carrier and his wife was of subtype ayw. Interestingly, the amplified HBV DNA from the five other members of the family was found to be not only of subtype adw but also contained G to A mutation at nucleotide position 587. This indicates the presence of established vaccine escape mutant of the virus (G145R) and suggests two different sources of infection within the family. Southern blot hybridization of EcoR1 digested DNA from PBL indicated presence of HBV DNA, integrated into cellular DNA and also in the form of free viral DNA. The study not only establishes the persistence of surface mutant G145R HBV DNA, within the PBL of HBsAg negative individuals from the non-vaccinated random population, but also suggests possible horizontal transmission of the mutant among the family members although none of the family members has received immunoprophylaxis against HBV or had clinically apparent disease or any other known risk factors of HBV infection. As all of them were seronegative for HBsAg/antiHBc, the presence of G145R mutant in the PBL signaled possibility of spread of the vaccine escape mutant virus by blood transfusion, unsafe injection practices or through sexual root. 相似文献
69.
dos Santos CN Rocha CF Cordeiro M Fragoso SP Rey F Deubel V Desprès P 《Virus research》2002,90(1-2):197-205
We have investigated the genetic diversity of dengue type-1 (DEN-1) virus in Brazil. The full nucleotide sequences of three DEN-1 virus isolated from DEN fever (DF) and DEN hemorrhagic fever patients in northeastern Brazil in 1997 (BR/97) and one from a DF patient in the south of Brazil in 2001 (BR/01) were compared to that of the reference strain BR/90 obtained in the city of Rio de Janeiro in 1990. Sequence analysis showed that the structural proteins were remarkably conserved between all isolates. A total of 27 amino acid changes occurred throughout the non-structural proteins. Among them, nine amino acid substitutions were specific of BR/97 and BR/01 isolates, indicating that in situ evolution of these strains had occurred. Within the BR/97 and BR/01 samples, some amino acid substitutions have been previously identified in DEN-1 virus strains sequenced so far, suggesting that recombination events might have occurred. 相似文献
70.
We describe a novel HLA-A*02 allele, A*0224, that was identified after a comparison of DNA and serological typing revealed a discrepancy in the HLA-A types: HLA-A2 was defined by serology but was not detected by the polymerase chain reaction using sequence-specific primers (PCR-SSP). DNA sequencing indicated the presence of a variant HLA-A*02 allele that differed from A*0201 by a single base (C/A) at position 453. This base substitution corresponded to the annealing site of a primer common to the two A*02-amplifying PCR-SSP mixtures used in the method. This provides an explanation for the results and highlights a limitation of PCR-SSP methods even where two PCR mixtures are used to detect alleles. Serological titration studies suggested that A*0201, A*0205 and A*0224 are unlikely to be differentiated during routine serological typing. 相似文献