排序方式: 共有74条查询结果,搜索用时 281 毫秒
51.
Sabeti PC Reich DE Higgins JM Levine HZ Richter DJ Schaffner SF Gabriel SB Platko JV Patterson NJ McDonald GJ Ackerman HC Campbell SJ Altshuler D Cooper R Kwiatkowski D Ward R Lander ES 《Nature》2002,419(6909):832-837
The ability to detect recent natural selection in the human population would have profound implications for the study of human history and for medicine. Here, we introduce a framework for detecting the genetic imprint of recent positive selection by analysing long-range haplotypes in human populations. We first identify haplotypes at a locus of interest (core haplotypes). We then assess the age of each core haplotype by the decay of its association to alleles at various distances from the locus, as measured by extended haplotype homozygosity (EHH). Core haplotypes that have unusually high EHH and a high population frequency indicate the presence of a mutation that rose to prominence in the human gene pool faster than expected under neutral evolution. We applied this approach to investigate selection at two genes carrying common variants implicated in resistance to malaria: G6PD and CD40 ligand. At both loci, the core haplotypes carrying the proposed protective mutation stand out and show significant evidence of selection. More generally, the method could be used to scan the entire genome for evidence of recent positive selection. 相似文献
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Honeybee colonies achieve fitness through dancing 总被引:4,自引:0,他引:4
The honeybee dance language, in which foragers perform dances containing information about the distance and direction to food sources, is the quintessential example of symbolic communication in non-primates. The dance language has been the subject of controversy, and of extensive research into the mechanisms of acquiring, decoding and evaluating the information in the dance. The dance language has been hypothesized, but not shown, to increase colony food collection. Here we show that colonies with disoriented dances (lacking direction information) recruit less effectively to syrup feeders than do colonies with oriented dances. For colonies foraging at natural sources, the direction information sometimes increases food collected, but at other times it makes no difference. The food-location information in the dance is presumably important when food sources are hard to find, variable in richness and ephemeral. Recruitment based simply on arousal of foragers and communication of floral odour, as occurs in honeybees, bumble bees and some stingless bees, can be equally effective under other circumstances. Clarifying the condition-dependent payoffs of the dance language provides new insight into its function in honeybee ecology. 相似文献
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It is thought that the Northern Hemisphere experienced only ephemeral glaciations from the Late Eocene to the Early Pliocene epochs (about 38 to 4 million years ago), and that the onset of extensive glaciations did not occur until about 3 million years ago. Several hypotheses have been proposed to explain this increase in Northern Hemisphere glaciation during the Late Pliocene. Here we use a fully coupled atmosphere-ocean general circulation model and an ice-sheet model to assess the impact of the proposed driving mechanisms for glaciation and the influence of orbital variations on the development of the Greenland ice sheet in particular. We find that Greenland glaciation is mainly controlled by a decrease in atmospheric carbon dioxide during the Late Pliocene. By contrast, our model results suggest that climatic shifts associated with the tectonically driven closure of the Panama seaway, with the termination of a permanent El Ni?o state or with tectonic uplift are not large enough to contribute significantly to the growth of the Greenland ice sheet; moreover, we find that none of these processes acted as a priming mechanism for glacial inception triggered by variations in the Earth's orbit. 相似文献
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Warren WC Hillier LW Marshall Graves JA Birney E Ponting CP Grützner F Belov K Miller W Clarke L Chinwalla AT Yang SP Heger A Locke DP Miethke P Waters PD Veyrunes F Fulton L Fulton B Graves T Wallis J Puente XS López-Otín C Ordóñez GR Eichler EE Chen L Cheng Z Deakin JE Alsop A Thompson K Kirby P Papenfuss AT Wakefield MJ Olender T Lancet D Huttley GA Smit AF Pask A Temple-Smith P Batzer MA Walker JA Konkel MK Harris RS Whittington CM Wong ES Gemmell NJ Buschiazzo E Vargas Jentzsch IM Merkel A 《Nature》2008,453(7192):175-183
We present a draft genome sequence of the platypus, Ornithorhynchus anatinus. This monotreme exhibits a fascinating combination of reptilian and mammalian characters. For example, platypuses have a coat of fur adapted to an aquatic lifestyle; platypus females lactate, yet lay eggs; and males are equipped with venom similar to that of reptiles. Analysis of the first monotreme genome aligned these features with genetic innovations. We find that reptile and platypus venom proteins have been co-opted independently from the same gene families; milk protein genes are conserved despite platypuses laying eggs; and immune gene family expansions are directly related to platypus biology. Expansions of protein, non-protein-coding RNA and microRNA families, as well as repeat elements, are identified. Sequencing of this genome now provides a valuable resource for deep mammalian comparative analyses, as well as for monotreme biology and conservation. 相似文献
55.
Genetic Analysis of Psoriasis Consortium & the Wellcome Trust Case Control Consortium Strange A Capon F Spencer CC Knight J Weale ME Allen MH Barton A Band G Bellenguez C Bergboer JG Blackwell JM Bramon E Bumpstead SJ Casas JP Cork MJ Corvin A Deloukas P Dilthey A Duncanson A Edkins S Estivill X Fitzgerald O Freeman C Giardina E Gray E Hofer A Hüffmeier U Hunt SE Irvine AD Jankowski J Kirby B Langford C Lascorz J Leman J Leslie S Mallbris L Markus HS Mathew CG McLean WH McManus R 《Nature genetics》2010,42(11):985-990
To identify new susceptibility loci for psoriasis, we undertook a genome-wide association study of 594,224 SNPs in 2,622 individuals with psoriasis and 5,667 controls. We identified associations at eight previously unreported genomic loci. Seven loci harbored genes with recognized immune functions (IL28RA, REL, IFIH1, ERAP1, TRAF3IP2, NFKBIA and TYK2). These associations were replicated in 9,079 European samples (six loci with a combined P < 5 × 10?? and two loci with a combined P < 5 × 10??). We also report compelling evidence for an interaction between the HLA-C and ERAP1 loci (combined P = 6.95 × 10??). ERAP1 plays an important role in MHC class I peptide processing. ERAP1 variants only influenced psoriasis susceptibility in individuals carrying the HLA-C risk allele. Our findings implicate pathways that integrate epidermal barrier dysfunction with innate and adaptive immune dysregulation in psoriasis pathogenesis. 相似文献
56.
Wain LV Verwoert GC O'Reilly PF Shi G Johnson T Johnson AD Bochud M Rice KM Henneman P Smith AV Ehret GB Amin N Larson MG Mooser V Hadley D Dörr M Bis JC Aspelund T Esko T Janssens AC Zhao JH Heath S Laan M Fu J Pistis G Luan J Arora P Lucas G Pirastu N Pichler I Jackson AU Webster RJ Zhang F Peden JF Schmidt H Tanaka T Campbell H Igl W Milaneschi Y Hottenga JJ Vitart V Chasman DI Trompet S Bragg-Gresham JL Alizadeh BZ Chambers JC Guo X Lehtimäki T Kühnel B Lopez LM Polašek O Boban M Nelson CP 《Nature genetics》2011,43(10):1005-1011
Numerous genetic loci have been associated with systolic blood pressure (SBP) and diastolic blood pressure (DBP) in Europeans. We now report genome-wide association studies of pulse pressure (PP) and mean arterial pressure (MAP). In discovery (N = 74,064) and follow-up studies (N = 48,607), we identified at genome-wide significance (P = 2.7 × 10(-8) to P = 2.3 × 10(-13)) four new PP loci (at 4q12 near CHIC2, 7q22.3 near PIK3CG, 8q24.12 in NOV and 11q24.3 near ADAMTS8), two new MAP loci (3p21.31 in MAP4 and 10q25.3 near ADRB1) and one locus associated with both of these traits (2q24.3 near FIGN) that has also recently been associated with SBP in east Asians. For three of the new PP loci, the estimated effect for SBP was opposite of that for DBP, in contrast to the majority of common SBP- and DBP-associated variants, which show concordant effects on both traits. These findings suggest new genetic pathways underlying blood pressure variation, some of which may differentially influence SBP and DBP. 相似文献
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Haiman CA Patterson N Freedman ML Myers SR Pike MC Waliszewska A Neubauer J Tandon A Schirmer C McDonald GJ Greenway SC Stram DO Le Marchand L Kolonel LN Frasco M Wong D Pooler LC Ardlie K Oakley-Girvan I Whittemore AS Cooney KA John EM Ingles SA Altshuler D Henderson BE Reich D 《Nature genetics》2007,39(5):638-644
After the recent discovery that common genetic variation in 8q24 influences inherited risk of prostate cancer, we genotyped 2,973 SNPs in up to 7,518 men with and without prostate cancer from five populations. We identified seven risk variants, five of them previously undescribed, spanning 430 kb and each independently predicting risk for prostate cancer (P = 7.9 x 10(-19) for the strongest association, and P < 1.5 x 10(-4) for five of the variants, after controlling for each of the others). The variants define common genotypes that span a more than fivefold range of susceptibility to cancer in some populations. None of the prostate cancer risk variants aligns to a known gene or alters the coding sequence of an encoded protein. 相似文献
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The genome of the mesopolyploid crop species Brassica rapa 总被引:21,自引:0,他引:21
Wang X Wang H Wang J Sun R Wu J Liu S Bai Y Mun JH Bancroft I Cheng F Huang S Li X Hua W Wang J Wang X Freeling M Pires JC Paterson AH Chalhoub B Wang B Hayward A Sharpe AG Park BS Weisshaar B Liu B Li B Liu B Tong C Song C Duran C Peng C Geng C Koh C Lin C Edwards D Mu D Shen D Soumpourou E Li F Fraser F Conant G Lassalle G King GJ Bonnema G Tang H Wang H Belcram H Zhou H Hirakawa H Abe H Guo H Wang H Jin H Parkin IA Batley J Kim JS Just J Li J Xu J Deng J Kim JA Li J Yu J Meng J Wang J Min J 《Nature genetics》2011,43(10):1035-1039
We report the annotation and analysis of the draft genome sequence of Brassica rapa accession Chiifu-401-42, a Chinese cabbage. We modeled 41,174 protein coding genes in the B. rapa genome, which has undergone genome triplication. We used Arabidopsis thaliana as an outgroup for investigating the consequences of genome triplication, such as structural and functional evolution. The extent of gene loss (fractionation) among triplicated genome segments varies, with one of the three copies consistently retaining a disproportionately large fraction of the genes expected to have been present in its ancestor. Variation in the number of members of gene families present in the genome may contribute to the remarkable morphological plasticity of Brassica species. The B. rapa genome sequence provides an important resource for studying the evolution of polyploid genomes and underpins the genetic improvement of Brassica oil and vegetable crops. 相似文献