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31.
An SNP map of human chromosome 22 总被引:35,自引:0,他引:35
Mullikin JC Hunt SE Cole CG Mortimore BJ Rice CM Burton J Matthews LH Pavitt R Plumb RW Sims SK Ainscough RM Attwood J Bailey JM Barlow K Bruskiewich RM Butcher PN Carter NP Chen Y Clee CM Coggill PC Davies J Davies RM Dawson E Francis MD Joy AA Lamble RG Langford CF Macarthy J Mall V Moreland A Overton-Larty EK Ross MT Smith LC Steward CA Sulston JE Tinsley EJ Turney KJ Willey DL Wilson GD McMurray AA Dunham I Rogers J Bentley DR 《Nature》2000,407(6803):516-520
The human genome sequence will provide a reference for measuring DNA sequence variation in human populations. Sequence variants are responsible for the genetic component of individuality, including complex characteristics such as disease susceptibility and drug response. Most sequence variants are single nucleotide polymorphisms (SNPs), where two alternate bases occur at one position. Comparison of any two genomes reveals around 1 SNP per kilobase. A sufficiently dense map of SNPs would allow the detection of sequence variants responsible for particular characteristics on the basis that they are associated with a specific SNP allele. Here we have evaluated large-scale sequencing approaches to obtaining SNPs, and have constructed a map of 2,730 SNPs on human chromosome 22. Most of the SNPs are within 25 kilobases of a transcribed exon, and are valuable for association studies. We have scaled up the process, detecting over 65,000 SNPs in the genome as part of The SNP Consortium programme, which is on target to build a map of 1 SNP every 5 kilobases that is integrated with the human genome sequence and that is freely available in the public domain. 相似文献
32.
Homology between Streptomyces genes coding for synthesis of different polyketides used to clone antibiotic biosynthetic genes 总被引:5,自引:0,他引:5
F Malpartida S E Hallam H M Kieser H Motamedi C R Hutchinson M J Butler D A Sugden M Warren C McKillop C R Bailey 《Nature》1987,325(6107):818-821
Many important antibiotics such as tetracyclines, erythromycin, adriamycin, monensin, rifamycin and avermectins are polyketides. In their biosynthesis, multifunctional synthases catalyse iterated condensation of thio-esters derived from acetate, propionate or butyrate to yield aliphatic chains of varying length and carrying different alkyl substituents. Subsequent modifications, including aromatic or macrolide ring closure or specific methylations or glycosylations, generate further chemical diversity. It has been suggested that, if different polyketide synthases had a common evolutionary origin, cloned DNA coding for one synthase might be used as a hybridization probe for the isolation of others. We show here that this is indeed possible. Study of a range of such synthase genes and their products should help to elucidate what determines the choice and order of condensation of different residues in polyketide assembly, and might yield, by in vitro recombination or mutagenesis, synthase genes capable of producing novel antibiotics. Moreover, because genes for entire antibiotic pathways are usually clustered in Streptomyces, cloned polyketide synthase genes are valuable in giving access to groups of linked biosynthetic genes. 相似文献
33.
Hartnup disorder is caused by mutations in the gene encoding the neutral amino acid transporter SLC6A19 总被引:7,自引:0,他引:7
Seow HF Bröer S Bröer A Bailey CG Potter SJ Cavanaugh JA Rasko JE 《Nature genetics》2004,36(9):1003-1007
Hartnup disorder (OMIM 234500) is an autosomal recessive abnormality of renal and gastrointestinal neutral amino acid transport noted for its clinical variability. We localized a gene causing Hartnup disorder to chromosome 5p15.33 and cloned a new gene, SLC6A19, in this region. SLC6A19 is a sodium-dependent and chloride-independent neutral amino acid transporter, expressed predominately in kidney and intestine, with properties of system B(0). We identified six mutations in SLC6A19 that cosegregated with disease in the predicted recessive manner, with most affected individuals being compound heterozygotes. The disease-causing mutations that we tested reduced neutral amino acid transport function in vitro. Population frequencies for the most common mutated SLC6A19 alleles are 0.007 for 517G --> A and 0.001 for 718C --> T. Our findings indicate that SLC6A19 is the long-sought gene that is mutated in Hartnup disorder; its identification provides the opportunity to examine the inconsistent multisystemic features of this disorder. 相似文献
34.
Madison E. Stellfox Aaron O. Bailey Daniel R. Foltz 《Cellular and molecular life sciences : CMLS》2013,70(3):387-406
The centromere is the chromosomal region that directs kinetochore assembly during mitosis in order to facilitate the faithful segregation of sister chromatids. The location of the human centromere is epigenetically specified. The presence of nucleosomes that contain the histone H3 variant, CENP-A, are thought to be the epigenetic mark that indicates active centromeres. Maintenance of centromeric identity requires the deposition of new CENP-A nucleosomes with each cell cycle. During S-phase, existing CENP-A nucleosomes are divided among the daughter chromosomes, while new CENP-A nucleosomes are deposited during early G1. The specific assembly of CENP-A nucleosomes at centromeres requires the Mis18 complex, which recruits the CENP-A assembly factor, HJURP. We will review the unique features of centromeric chromatin as well as the mechanism of CENP-A nucleosome deposition. We will also highlight a few recent discoveries that begin to elucidate the factors that temporally and spatially control CENP-A deposition. 相似文献
35.
Kenneth D. Bailey 《Systemic Practice and Action Research》1995,8(1):85-106
Space, especially physical or geographical space, is a very important concept in living systems theory (LST). Indeed, along with time, it is included in the very definition of a concrete living system. But while time has its own critical subsystem in LST, space receives relative neglect. There is no space subsystem, but space is discussed in the boundary and supporter subsystems. The problem here is that discussion of the boundary emphasizes the regulation of matter-energy and information flows, while discussion of the supporter emphasizes vertical support rather than lateral spacing. The purpose of this paper is to rectify the relative neglect of spacing by unifying the scattered discussion of space in LST. After discussing space in the boundary and supporter subsystems at six levels (the organism, group, organization, community, society, and supranational), the paper extends and complements the literature of LST by discussing additional relevant literature on space, and by discussing possible applications at the six levels. 相似文献
36.
37.
Cheung VG Nowak N Jang W Kirsch IR Zhao S Chen XN Furey TS Kim UJ Kuo WL Olivier M Conroy J Kasprzyk A Massa H Yonescu R Sait S Thoreen C Snijders A Lemyre E Bailey JA Bruzel A Burrill WD Clegg SM Collins S Dhami P Friedman C Han CS Herrick S Lee J Ligon AH Lowry S Morley M Narasimhan S Osoegawa K Peng Z Plajzer-Frick I Quade BJ Scott D Sirotkin K Thorpe AA Gray JW Hudson J Pinkel D Ried T Rowen L Shen-Ong GL Strausberg RL Birney E Callen DF Cheng JF Cox DR Doggett NA Carter NP Eichler EE 《Nature》2001,409(6822):953-958
We have placed 7,600 cytogenetically defined landmarks on the draft sequence of the human genome to help with the characterization of genes altered by gross chromosomal aberrations that cause human disease. The landmarks are large-insert clones mapped to chromosome bands by fluorescence in situ hybridization. Each clone contains a sequence tag that is positioned on the genomic sequence. This genome-wide set of sequence-anchored clones allows structural and functional analyses of the genome. This resource represents the first comprehensive integration of cytogenetic, radiation hybrid, linkage and sequence maps of the human genome; provides an independent validation of the sequence map and framework for contig order and orientation; surveys the genome for large-scale duplications, which are likely to require special attention during sequence assembly; and allows a stringent assessment of sequence differences between the dark and light bands of chromosomes. It also provides insight into large-scale chromatin structure and the evolution of chromosomes and gene families and will accelerate our understanding of the molecular bases of human disease and cancer. 相似文献
38.
Wojtek J. Krzanowski Trevor C. Bailey Derek Partridge Jonathan E. Fieldsend Richard M. Everson Vitaly Schetinin 《Journal of Classification》2006,23(2):199-220
Bayesian classification is currently of considerable interest. It provides a strategy for eliminating the uncertainty associated
with a particular choice of classifiermodel parameters, and is the optimal decision-theoretic choice under certain circumstances
when there is no single “true” classifier for a given data set. Modern computing capabilities can easily support the Markov
chain Monte Carlo sampling that is necessary to carry out the calculations involved, but the information available in these
samples is not at present being fully utilised. We show how it can be allied to known results concerning the “reject option”
in order to produce an assessment of the confidence that can be ascribed to particular classifications, and how these confidence
measures can be used to compare the performances of classifiers. Incorporating these confidence measures can alter the apparent
ranking of classifiers as given by straightforward success or error rates. Several possible methods for obtaining confidence
assessments are described, and compared on a range of data sets using the Bayesian probabilistic nearest-neighbour classifier. 相似文献
39.
Mungall AJ Palmer SA Sims SK Edwards CA Ashurst JL Wilming L Jones MC Horton R Hunt SE Scott CE Gilbert JG Clamp ME Bethel G Milne S Ainscough R Almeida JP Ambrose KD Andrews TD Ashwell RI Babbage AK Bagguley CL Bailey J Banerjee R Barker DJ Barlow KF Bates K Beare DM Beasley H Beasley O Bird CP Blakey S Bray-Allen S Brook J Brown AJ Brown JY Burford DC Burrill W Burton J Carder C Carter NP Chapman JC Clark SY Clark G Clee CM Clegg S Cobley V Collier RE Collins JE Colman LK Corby NR Coville GJ 《Nature》2003,425(6960):805-811
40.
Nejentsev S Howson JM Walker NM Szeszko J Field SF Stevens HE Reynolds P Hardy M King E Masters J Hulme J Maier LM Smyth D Bailey R Cooper JD Ribas G Campbell RD Clayton DG Todd JA;Wellcome Trust Case Control Consortium 《Nature》2007,450(7171):887-892
The major histocompatibility complex (MHC) on chromosome 6 is associated with susceptibility to more common diseases than any other region of the human genome, including almost all disorders classified as autoimmune. In type 1 diabetes the major genetic susceptibility determinants have been mapped to the MHC class II genes HLA-DQB1 and HLA-DRB1 (refs 1-3), but these genes cannot completely explain the association between type 1 diabetes and the MHC region. Owing to the region's extreme gene density, the multiplicity of disease-associated alleles, strong associations between alleles, limited genotyping capability, and inadequate statistical approaches and sample sizes, which, and how many, loci within the MHC determine susceptibility remains unclear. Here, in several large type 1 diabetes data sets, we analyse a combined total of 1,729 polymorphisms, and apply statistical methods-recursive partitioning and regression-to pinpoint disease susceptibility to the MHC class I genes HLA-B and HLA-A (risk ratios >1.5; P(combined) = 2.01 x 10(-19) and 2.35 x 10(-13), respectively) in addition to the established associations of the MHC class II genes. Other loci with smaller and/or rarer effects might also be involved, but to find these, future searches must take into account both the HLA class II and class I genes and use even larger samples. Taken together with previous studies, we conclude that MHC-class-I-mediated events, principally involving HLA-B*39, contribute to the aetiology of type 1 diabetes. 相似文献