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排序方式: 共有346条查询结果,搜索用时 15 毫秒
91.
ATM mutations that cause ataxia-telangiectasia are breast cancer susceptibility alleles 总被引:13,自引:0,他引:13
Renwick A Thompson D Seal S Kelly P Chagtai T Ahmed M North B Jayatilake H Barfoot R Spanova K McGuffog L Evans DG Eccles D;Breast Cancer Susceptibility Collaboration 《Nature genetics》2006,38(8):873-875
We screened individuals from 443 familial breast cancer pedigrees and 521 controls for ATM sequence variants and identified 12 mutations in affected individuals and two in controls (P = 0.0047). The results demonstrate that ATM mutations that cause ataxia-telangiectasia in biallelic carriers are breast cancer susceptibility alleles in monoallelic carriers, with an estimated relative risk of 2.37 (95% confidence interval (c.i.) = 1.51-3.78, P = 0.0003). There was no evidence that other classes of ATM variant confer a risk of breast cancer. 相似文献
92.
It is important that migration is measured accurately, for example to inform population estimates and projections. However, current sources of information make it difficult to produce robust estimates of emigration from Great Britain. Several other countries, including Ireland, make use of household surveys in their estimates of migration. To investigate the feasibility of obtaining information on emigration from those resident in Great Britain, three questions were included in the Omnibus Survey for two months. Respondents were asked whether they had plans to emigrate or whether anyone in their family had recently emigrated or intended to shortly. This article reports on the results of this pilot, providing evidence on response levels, comparison with the International Passenger Survey and feedback from interviewers on the questions asked. 相似文献
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Tomlinson IP Webb E Carvajal-Carmona L Broderick P Howarth K Pittman AM Spain S Lubbe S Walther A Sullivan K Jaeger E Fielding S Rowan A Vijayakrishnan J Domingo E Chandler I Kemp Z Qureshi M Farrington SM Tenesa A Prendergast JG Barnetson RA Penegar S Barclay E Wood W Martin L Gorman M Thomas H Peto J Bishop DT Gray R Maher ER Lucassen A Kerr D Evans DG;CORGI Consortium Schafmayer C Buch S Völzke H Hampe J Schreiber S John U Koessler T Pharoah P van Wezel T Morreau H Wijnen JT Hopper JL 《Nature genetics》2008,40(5):623-630
To identify colorectal cancer (CRC) susceptibility alleles, we conducted a genome-wide association study. In phase 1, we genotyped 550,163 tagSNPs in 940 familial colorectal tumor cases (627 CRC, 313 high-risk adenoma) and 965 controls. In phase 2, we genotyped 42,708 selected SNPs in 2,873 CRC cases and 2,871 controls. In phase 3, we evaluated 11 SNPs showing association at P < 10(-4) in a joint analysis of phases 1 and 2 in 4,287 CRC cases and 3,743 controls. Two SNPs were taken forward to phase 4 genotyping (10,731 CRC cases and 10,961 controls from eight centers). In addition to the previously reported 8q24, 15q13 and 18q21 CRC risk loci, we identified two previously unreported associations: rs10795668, located at 10p14 (P = 2.5 x 10(-13) overall; P = 6.9 x 10(-12) replication), and rs16892766, at 8q23.3 (P = 3.3 x 10(-18) overall; P = 9.6 x 10(-17) replication), which tags a plausible causative gene, EIF3H. These data provide further evidence for the 'common-disease common-variant' model of CRC predisposition. 相似文献
96.
Cloning and sequence analysis of cDNA for bovine carboxypeptidase E 总被引:10,自引:0,他引:10
Carboxypeptidase E (enkephalin convertase) was first identified as the carboxypeptidase B-like enzyme involved in the biosynthesis of enkephalin in bovine adrenal chromaffin granules. A similar enzyme is present in many brain regions and in purified secretory granules from rat pituitary and rat insulinoma. Within the secretory granules, carboxypeptidase E (CPE) activity is found in both a soluble and a membrane-bound form, which differ slightly in relative molecular mass (Mr). Here, to investigate whether the CPE activities in the various tissues are produced from a single gene, purified CPE was partially sequenced and oligonucleotide probes were used to isolate a clone encoding CPE from a bovine pituitary complementary DNA library. This cDNA hybridizes to bovine pituitary poly(A)+ RNAs of approximately 3.3, 2.6 and 2.1 kilobases (kb), with the 3.3-kb messenger RNA the predominant species. The predicted amino-acid sequence of the cDNA clone contains the partially determined sequences of CPE, several pairs of basic amino acids and displays some homology with both carboxypeptidases A and B. Restriction analysis of bovine genomic DNA suggests only one gene for CPE. This is consistent with a broad role for CPE in the biosynthesis of many neuropeptides. 相似文献
97.
A family of related ATP-binding subunits coupled to many distinct biological processes in bacteria 总被引:135,自引:0,他引:135
C F Higgins I D Hiles G P Salmond D R Gill J A Downie I J Evans I B Holland L Gray S D Buckel A W Bell 《Nature》1986,323(6087):448-450
Many biological processes are coupled to ATP hydrolysis. We describe here a class of closely related ATP-binding proteins, from several bacterial species, which are associated with a variety of cellular functions including membrane transport, cell division, nodulation in Rhizobium and haemolysin export. These proteins comprise a family of structurally and functionally related subunits which share a common evolutionary origin, bind ATP and probably serve to couple ATP hydrolysis to each of these biological processes. This finding suggests a specific role for ATP in cell division, nodulation during nitrogen fixation and protein export, and allows us to assign a probable function to one of the protein components from each of these systems. 相似文献
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Porco CC Baker E Barbara J Beurle K Brahic A Burns JA Charnoz S Cooper N Dawson DD Del Genio AD Denk T Dones L Dyudina U Evans MW Fussner S Giese B Grazier K Helfenstein P Ingersoll AP Jacobson RA Johnson TV McEwen A Murray CD Neukum G Owen WM Perry J Roatsch T Spitale J Squyres S Thomas P Tiscareno M Turtle EP Vasavada AR Veverka J Wagner R West R 《Nature》2005,434(7030):159-168
Titan, the largest moon of Saturn, is the only satellite in the Solar System with a substantial atmosphere. The atmosphere is poorly understood and obscures the surface, leading to intense speculation about Titan's nature. Here we present observations of Titan from the imaging science experiment onboard the Cassini spacecraft that address some of these issues. The images reveal intricate surface albedo features that suggest aeolian, tectonic and fluvial processes; they also show a few circular features that could be impact structures. These observations imply that substantial surface modification has occurred over Titan's history. We have not directly detected liquids on the surface to date. Convective clouds are found to be common near the south pole, and the motion of mid-latitude clouds consistently indicates eastward winds, from which we infer that the troposphere is rotating faster than the surface. A detached haze at an altitude of 500 km is 150-200 km higher than that observed by Voyager, and more tenuous haze layers are also resolved. 相似文献
100.
Identification of the familial cylindromatosis tumour-suppressor gene 总被引:25,自引:0,他引:25
Bignell GR Warren W Seal S Takahashi M Rapley E Barfoot R Green H Brown C Biggs PJ Lakhani SR Jones C Hansen J Blair E Hofmann B Siebert R Turner G Evans DG Schrander-Stumpel C Beemer FA van Den Ouweland A Halley D Delpech B Cleveland MG Leigh I Leisti J Rasmussen S 《Nature genetics》2000,25(2):160-165
Familial cylindromatosis is an autosomal dominant genetic predisposition to multiple tumours of the skin appendages. The susceptibility gene (CYLD) has previously been localized to chromosome 16q and has the genetic attributes of a tumour-suppressor gene (recessive oncogene). Here we have identified CYLD by detecting germline mutations in 21 cylindromatosis families and somatic mutations in 1 sporadic and 5 familial cylindromas. All mutations predict truncation or absence of the encoded protein. CYLD encodes three cytoskeletal-associated-protein-glycine-conserved (CAP-GLY) domains, which are found in proteins that coordinate the attachment of organelles to microtubules. CYLD also has sequence homology to the catalytic domain of ubiquitin carboxy-terminal hydrolases (UCH). 相似文献