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排序方式: 共有237条查询结果,搜索用时 31 毫秒
61.
62.
Evolution of microRNA genes by inverted duplication of target gene sequences in Arabidopsis thaliana 总被引:8,自引:0,他引:8
Allen E Xie Z Gustafson AM Sung GH Spatafora JW Carrington JC 《Nature genetics》2004,36(12):1282-1290
63.
Allen M Heinzmann A Noguchi E Abecasis G Broxholme J Ponting CP Bhattacharyya S Tinsley J Zhang Y Holt R Jones EY Lench N Carey A Jones H Dickens NJ Dimon C Nicholls R Baker C Xue L Townsend E Kabesch M Weiland SK Carr D von Mutius E Adcock IM Barnes PJ Lathrop GM Edwards M Moffatt MF Cookson WO 《Nature genetics》2003,35(3):258-263
Asthma is a common disease in children and young adults. Four separate reports have linked asthma and related phenotypes to an ill-defined interval between 2q14 and 2q32 (refs. 1-4), and two mouse genome screens have linked bronchial hyper-responsiveness to the region homologous to 2q14 (refs. 5,6). We found and replicated association between asthma and the D2S308 microsatellite, 800 kb distal to the IL1 cluster on 2q14. We sequenced the surrounding region and constructed a comprehensive, high-density, single-nucleotide polymorphism (SNP) linkage disequilibrium (LD) map. SNP association was limited to the initial exons of a solitary gene of 3.6 kb (DPP10), which extends over 1 Mb of genomic DNA. DPP10 encodes a homolog of dipeptidyl peptidases (DPPs) that cleave terminal dipeptides from cytokines and chemokines, and it presents a potential new target for asthma therapy. 相似文献
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65.
Antigens present during neonatal life are recognized as self and individuals are tolerant to these antigens. In normal individuals T cells are tolerant to most self proteins but we still know little of the mechanism(s) by which tolerance is established. A requisite part of the current negative selection model of self tolerance is the expression of self proteins complexed with major histocompatibility complex molecules in the thymus. As MHC proteins bind antigens and present them to the receptor on the antigen-specific T cell, then for tolerance to self to occur, it is possible that each self protein must be processed and presented by an MHC molecule. As a result of the development of a unique T-cell hybrid reactive to the self protein murine haemoglobin, we have shown that in normal animals this self protein is continuously processed and potentially presented in an MHC-restricted manner. Here we show that self haemoglobin is being processed and presented by thymic antigen-presenting cells as early as gestational day 14. We also demonstrate that three types of thymic stromal cells, namely macrophages, dendritic cells and cortical epithelial cells, can present the haemoglobin self antigen in vivo. This surprising presentation of a self antigen by thymic cortical epithelial cells implies that they could be involved in T-cell development and negative selection. 相似文献
66.
Several recent studies have suggested that interactions between thymocytes and thymic stromal cells are essential for the development and elimination of antigen-reactive T lymphocytes. It is important, therefore, to characterize the stromal cells involved in presentation of antigen in the thymus. In a previous report, we demonstrated, using T-cell hybridomas, that three distinct types of antigen presenting cells in the thymus (cortical epithelial cells, macrophages, and dendritic cells) constitutively expressed self haemoglobin/Ia complexes. Here we report that one of these cell types, the cortical epithelial cell, does not induce stimulation of T-lymphocyte clones even though the antigen/Ia complex required for antigen-specific recognition is present. This lack of response occurs with both TH1 and TH2 clones. Responsiveness of the TH2 clone can be restored by adding the murine lymphokine interleukin-1 beta to the culture system. 相似文献
67.
Speliotes EK Willer CJ Berndt SI Monda KL Thorleifsson G Jackson AU Lango Allen H Lindgren CM Luan J Mägi R Randall JC Vedantam S Winkler TW Qi L Workalemahu T Heid IM Steinthorsdottir V Stringham HM Weedon MN Wheeler E Wood AR Ferreira T Weyant RJ Segrè AV Estrada K Liang L Nemesh J Park JH Gustafsson S Kilpeläinen TO Yang J Bouatia-Naji N Esko T Feitosa MF Kutalik Z Mangino M Raychaudhuri S Scherag A Smith AV Welch R Zhao JH Aben KK Absher DM Amin N Dixon AL Fisher E Glazer NL Goddard ME 《Nature genetics》2010,42(11):937-948
Obesity is globally prevalent and highly heritable, but its underlying genetic factors remain largely elusive. To identify genetic loci for obesity susceptibility, we examined associations between body mass index and ~ 2.8 million SNPs in up to 123,865 individuals with targeted follow up of 42 SNPs in up to 125,931 additional individuals. We confirmed 14 known obesity susceptibility loci and identified 18 new loci associated with body mass index (P < 5 × 10??), one of which includes a copy number variant near GPRC5B. Some loci (at MC4R, POMC, SH2B1 and BDNF) map near key hypothalamic regulators of energy balance, and one of these loci is near GIPR, an incretin receptor. Furthermore, genes in other newly associated loci may provide new insights into human body weight regulation. 相似文献
68.
Todd JA Walker NM Cooper JD Smyth DJ Downes K Plagnol V Bailey R Nejentsev S Field SF Payne F Lowe CE Szeszko JS Hafler JP Zeitels L Yang JH Vella A Nutland S Stevens HE Schuilenburg H Coleman G Maisuria M Meadows W Smink LJ Healy B Burren OS Lam AA Ovington NR Allen J Adlem E Leung HT Wallace C Howson JM Guja C Ionescu-Tîrgovişte C;Genetics of Type Diabetes in Finland Simmonds MJ Heward JM Gough SC;Wellcome Trust Case Control Consortium Dunger DB Wicker LS Clayton DG 《Nature genetics》2007,39(7):857-864
The Wellcome Trust Case Control Consortium (WTCCC) primary genome-wide association (GWA) scan on seven diseases, including the multifactorial autoimmune disease type 1 diabetes (T1D), shows associations at P < 5 x 10(-7) between T1D and six chromosome regions: 12q24, 12q13, 16p13, 18p11, 12p13 and 4q27. Here, we attempted to validate these and six other top findings in 4,000 individuals with T1D, 5,000 controls and 2,997 family trios independent of the WTCCC study. We confirmed unequivocally the associations of 12q24, 12q13, 16p13 and 18p11 (P(follow-up) 相似文献
69.
Salmincola californiensis is a parasitic copepod in the Lernaeopodidae family that commonly parasitizes salmonid fishes ( Oncorhynchus spp.) by attaching near the fins and on gill filaments. Historically their distribution was limited to streams that emptied into the Pacific Ocean. During the summer of 2006, several rainbow trout ( Oncorhynchus mykiss ) captured in Lake Tahoe were infested with S. californiensis . This is the first known record of S. californiensis in Lake Tahoe. 相似文献
70.
Allen NC Bagade S McQueen MB Ioannidis JP Kavvoura FK Khoury MJ Tanzi RE Bertram L 《Nature genetics》2008,40(7):827-834
In an effort to pinpoint potential genetic risk factors for schizophrenia, research groups worldwide have published over 1,000 genetic association studies with largely inconsistent results. To facilitate the interpretation of these findings, we have created a regularly updated online database of all published genetic association studies for schizophrenia ('SzGene'). For all polymorphisms having genotype data available in at least four independent case-control samples, we systematically carried out random-effects meta-analyses using allelic contrasts. Across 118 meta-analyses, a total of 24 genetic variants in 16 different genes (APOE, COMT, DAO, DRD1, DRD2, DRD4, DTNBP1, GABRB2, GRIN2B, HP, IL1B, MTHFR, PLXNA2, SLC6A4, TP53 and TPH1) showed nominally significant effects with average summary odds ratios of approximately 1.23. Seven of these variants had not been previously meta-analyzed. According to recently proposed criteria for the assessment of cumulative evidence in genetic association studies, four of the significant results can be characterized as showing 'strong' epidemiological credibility. Our project represents the first comprehensive online resource for systematically synthesized and graded evidence of genetic association studies in schizophrenia. As such, it could serve as a model for field synopses of genetic associations in other common and genetically complex disorders. 相似文献