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991.
Satoshi Fujishita Noritoshi Shibuya Norio Niikawa Shigenobu Nagataki 《Journal of human genetics》1991,36(4):317-324
Polymerase chain reaction (PCR)-based diagnosis was carried out in 62 patients (57 probands) with Duchenne or Becker muscular dystrophy (DMD or BMD) and 226 members in 57 families. The PCR studies were also performed for carrier detection in 57 mothers and 58 sisters, and prenatal diagnosis of 4 fetuses at risk of DMD. The PCR with 7 sets of primers, which amplify 7 different exon-sequences of the dystrophin gene, detected gene deletion of at least one exon in 49% of the probands. The PCR with the other 4 primer sets, which amplify 3 intragenic loci, and subsequent endonuclease digestion detected in 84% of the mothers a heterozygous pattern in at least one such locus/segment. Using the same primer sets, carrier detection was successful in 5 sisters of familial DMD cases, while recombination between the ERT87 and the 3 end intragenic loci was observed in 11% of family members studied. Prenatal diagnosis was made in all the 4 fetuses; two males were affected, one male fetus non-affected, and the remaining one female fetus a carrier. Thus, the PCR study and the primers used in the present study are useful and convincing for rapid diagnosis of DMD and/or BMD. 相似文献
992.
The adaptive immune system has to economically generate a large array of T and B cell antigen receptors (T cell receptors
[TCRs], B cell receptors [BCRs]) that eliminate both longstanding and novel antigens from the host while preventing the production
of deleterious (e.g., autoreactive) antigen receptors. Our studies focus on the mechanisms that shape the development of these
antigen receptor repertoies during human ontogeny. The key to BCR and TCR diversity is the third complementarity determining
region (CDR3) of the variable domain, which in the immunoglobulin heavy chain and TCR β chain, is created by the junction
between the variable, diversity, and joining gene segments. The CDR3 diversity is constrained by overrepresentation of gene
segments and lack of N regions during the first trimester of gestation and then increases exponentially during ontogeny until
it reaches adult levels months after birth. This process parallels, and may contribute to, the stepwise acquisition of the
ability to respond to specific antigens. Recent studies indicate that maturation of the CDR 3 repertoire is not accelerated
by premature exposition to extrauterine antigen and thus appears to follow a strictly developmentally regulated program whose
pacemaker(s) is still unknown. 相似文献
993.
Euy Kyun Shin Fumihiko Matsuda Junji Fujikura Takashi Akamizu Hideo Sugawa Toru Mori Tasuku Honjo 《European journal of immunology》1993,23(9):2365-2367
In an Epstein-Barr virus-transformed human B cell line we found an unusual immunoglobulin heavy chain gene rearrangement. Restriction mapping and sequencing analysis led us to conclude that VH-D and D-JH recombination took place in a single allele. Both VH-D and D-JH complexes still had their recombination signal sequences adjacent and the DNA sandwiched by these two complexes retained a germ line configuration, suggesting the potential for a secondary rearrangement resulting in a VH-D(-D)-JH formation. With this finding, we propose a novel pathway, in which the VH-D complex is an intermediate in the formation of a functional VH exon. 相似文献
994.
We have employed the single strand conformation polymorphism (SSCP) technique to examine a group of patients with Duchenne or Becker muscular dystrophy who do not contain deletions detectable by multiplex PCR or Southern/cDNA, in an attempt to identify uncommon mutations within the dystrophin gene. In SSCP analysis, a mutated sequence can be detected as a change of mobility in a nondenaturing polyacrylamide gel. During the course of this investigation, we detected and characterized a new polymorphism at the 3' end of intron 16. The G-to-T base change creates a TaqI restriction site which allows for rapid typing of the polymorphism by restriction digestion and electrophoresis of PCR amplified products. Its localization inside the 5' region of the dystrophin gene and its high heterozygosity makes it a useful and easy tool for rapid carrier and prenatal diagnosis. 相似文献
995.
996.
PMX2B,a new candidate gene for Hirschsprung's disease 总被引:7,自引:0,他引:7
Benailly HK Lapierre JM Laudier B Amiel J Attié T De Blois MC Vekemans M Romana SP 《Clinical genetics》2003,64(3):204-209
Hirschsprung's (HSCR) disease is a congenital intestinal malformation of the enteric nervous system. It is a multigenic malformation and until now, eight genes have been involved in the etiology of this disease: genes encoding proteins of the RET signaling pathway (RET, GDNF and NTN), genes participating in the endothelin (EDN) type B receptor pathway (EDNRB, EDN3 and ECE-1), the SOX10 gene and the SIP1 gene that is mutated in syndromic forms of HSCR. Mutations of these genes are found in not more than 50-60% of affected individuals. Here, we report on the results of a molecular cytogenetic study performed in a girl who presented with a syndromic short segment HSCR associated with a de novo t(4;8)(p13;p22) translocation. A comparative genomic hybridization (CGH) study found a 4p12p13 deletion. A molecular characterization of this rearrangement showed that the 4p13 deletion was 5 Mb in length and included the paired mesoderm homeobox gene (PMX2B) (MIM 603851), a gene expressed in the human embryonic gut and essential for the development of autonomic neural crest derivatives. The present observation suggests that PMX2B haploinsuffciency might predispose to HSCR. 相似文献
997.
中国东北汉族一个先天性白内障家系致病基因的鉴定 总被引:5,自引:0,他引:5
目的鉴定一个先天性白内障家系的致病基因。方法根据已知与先天性白内障有关的12个致病基因的染色体上的定位,分别选取3~4个的微卫星标记位点,对该家系进行连锁分析。通过测序鉴定致病基因。结果在1q21.1GJA8位点显示最大Lod值2.44。致病基因定位于1q21.1区的GJA8基因,构成缝隙连接的缝隙连接蛋白Connexin50。DNA序列分析鉴定显示其第2外显子的第191个碱基杂合突变T>G导致其蛋白产物第64位缬氨酸转变为甘氨酸。结论Connexin50的V64G新生突变是导致该家系的致病原因。 相似文献
998.
Erika L. D. Mitchell Gavin R. M. White Mauro F. Santibanez-Koref Jenny M. Varley Jim Heighway 《Chromosome research》1995,3(4):261-262
The gene loci CDK4, GLI, CHOP and MDM2 have been mapped to the q13–q15 region of chromosome 12. Using fluorescencein situ hybridization onto simultaneously DAPI-banded metaphase chromosomes and interphase nuclei, we have more precisely mapped and ordered these loci, together with a number of Genethon microsatellite markers. GLI and CHOP localize to 12q13.3–14.1, CDK4 to 12q14 and MDM2 to 12q14.3–q15, and the gene order is cen-GLI/CHOP-CDK4-MDM2. The Genethon microsatellites D12S80 and D12S83 flank MDM2. 相似文献
999.
Exploratory activity: genetic analysis of its modification by scopolamine and amphetamine 总被引:3,自引:0,他引:3
Short-term exploratory activity was found to be significantly higher in C57BL/6By than in BALB/cBy inbred mice. Scopolamine reversed the activity levels in these strains. Basal exploratory activity levels and the effects of scopolamine on this behavioral measure assessed in these two strains, their reciprocal F1 hybrids, their recombinant inbred strains and three C57BL/6 congenic lines permitted characterization of a gene exerting a major effect on short-term exploratory activity [Exa, linked to H(w26), chromosome 4 (LG VIII)] and of a gene modulating the effects of scopolamine in this behavior, [Sco, linked to H-2, chromosome 17 (LG IX)]. Amphetamine exerted opposite effects in relation to those exerted by scopolamine on activity and its action was found to be determined by a polygenic system. 相似文献
1000.
目的实验研究靶向转染survivin的小分子干扰RNA(small interfering RNA,siRNA)对膀胱癌生物学行为的影响。方法设计1对survivin编码基因序列特异的siRNA,用脂质体转染T24膀胱癌细胞株。采用流式细胞术检测转染效率和细胞凋亡;荧光实时定量PCR检测干扰前后survivin的mRNA表达;用survivin的siRNA片段插入空载体后建立重组载体pRNAT-U6、1/Neo-survivin。结果脂质体转染T24细胞后的转染效率为92.3%;survivin编码基因序列特异的siRNA能有效下调survivin基因的表达,呈时间和剂量依赖性,最大效应浓度为100nmol/L,此时survivin表达水平下调了75.91%,并显著地抑制了细胞生长,抑制率达55.29%,差异有统计学意义(P〈0.01);细胞凋亡率亦增至45.70%,与对照相比差异有统计学意义(P〈0.01)。用限制性内切酶将空载体线性化,T4DNA连接酶将siRNA片段插入空载体中,对该重组表达载体进行鉴定,获得RNA干扰质粒载体pRNAT-U6.1/Neo-survivin。结论siRNA.survivin能显著下调膀胱癌细胞survivin基因表达水平,促进细胞凋亡,抑制肿瘤细胞增殖,可能成为膀胱癌基因治疗的新工具。成功构建的靶向survivin基因表达的RNA干扰质粒载体为进一步应用RNA干扰技术进行survivin基因功能研究奠定了基础。 相似文献