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排序方式: 共有192条查询结果,搜索用时 15 毫秒
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The occurrence of earthquakes in the lower crust near continental rifts has long been puzzling, as the lower crust is generally thought to be too hot for brittle failure to occur. Such anomalous events have usually been explained in terms of the lower crust being cooler than normal. But if the lower crust is indeed cold enough to produce earthquakes, then the uppermost mantle beneath it should also be cold enough, and yet uppermost mantle earthquakes are not observed. Numerous lower-crustal earthquakes occur near the southwestern termination of the Taupo Volcanic Zone (TVZ), an active continental rift in New Zealand. Here we present three-dimensional tomographic imaging of seismic velocities and seismic attenuation in this region using data from a dense seismograph deployment. We find that crustal earthquakes accurately relocated with our three-dimensional seismic velocity model form a continuous band along the rift, deepening from mostly less than 10 km in the central TVZ to depths of 30-40 km in the lower crust, 30 km southwest of the termination of the volcanic zone. These earthquakes often occur in swarms, suggesting fluid movement in critically loaded fault zones. Seismic velocities within the band are also consistent with the presence of fluids, and the deepening seismicity parallels the boundary between high seismic attenuation (interpreted as partial melt) within the central TVZ and low seismic attenuation in the crust to the southwest. This linking of upper and lower-crustal seismicity and crustal structure allows us to propose a common explanation for all the seismicity, involving the weakening of faults on the periphery of an otherwise dry, mafic crust by hot fluids, including those exsolved from underlying melt. Such fluids may generally be an important driver of lower-crustal seismicity near continental rifts. 相似文献
113.
Logan CV Lucke B Pottinger C Abdelhamed ZA Parry DA Szymanska K Diggle CP van Riesen A Morgan JE Markham G Ellis I Manzur AY Markham AF Shires M Helliwell T Scoto M Hübner C Bonthron DT Taylor GR Sheridan E Muntoni F Carr IM Schuelke M Johnson CA 《Nature genetics》2011,43(12):1189-1192
Infantile myopathies with diaphragmatic paralysis are genetically heterogeneous, and clinical symptoms do not assist in differentiating between them. We used phased haplotype analysis with subsequent targeted exome sequencing to identify MEGF10 mutations in a previously unidentified type of infantile myopathy with diaphragmatic weakness, areflexia, respiratory distress and dysphagia. MEGF10 is highly expressed in activated satellite cells and regulates their proliferation as well as their differentiation and fusion into multinucleated myofibers, which are greatly reduced in muscle from individuals with early onset myopathy, areflexia, respiratory distress and dysphagia. 相似文献
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de Bakker PI Burtt NP Graham RR Guiducci C Yelensky R Drake JA Bersaglieri T Penney KL Butler J Young S Onofrio RC Lyon HN Stram DO Haiman CA Freedman ML Zhu X Cooper R Groop L Kolonel LN Henderson BE Daly MJ Hirschhorn JN Altshuler D 《Nature genetics》2006,38(11):1298-1303
A general question for linkage disequilibrium-based association studies is how power to detect an association is compromised when tag SNPs are chosen from data in one population sample and then deployed in another sample. Specifically, it is important to know how well tags picked from the HapMap DNA samples capture the variation in other samples. To address this, we collected dense data uniformly across the four HapMap population samples and eleven other population samples. We picked tag SNPs using genotype data we collected in the HapMap samples and then evaluated the effective coverage of these tags in comparison to the entire set of common variants observed in the other samples. We simulated case-control association studies in the non-HapMap samples under a disease model of modest risk, and we observed little loss in power. These results demonstrate that the HapMap DNA samples can be used to select tags for genome-wide association studies in many samples around the world. 相似文献
117.
A worldwide survey of haplotype variation and linkage disequilibrium in the human genome 总被引:1,自引:0,他引:1
Conrad DF Jakobsson M Coop G Wen X Wall JD Rosenberg NA Pritchard JK 《Nature genetics》2006,38(11):1251-1260
Recent genomic surveys have produced high-resolution haplotype information, but only in a small number of human populations. We report haplotype structure across 12 Mb of DNA sequence in 927 individuals representing 52 populations. The geographic distribution of haplotypes reflects human history, with a loss of haplotype diversity as distance increases from Africa. Although the extent of linkage disequilibrium (LD) varies markedly across populations, considerable sharing of haplotype structure exists, and inferred recombination hotspot locations generally match across groups. The four samples in the International HapMap Project contain the majority of common haplotypes found in most populations: averaging across populations, 83% of common 20-kb haplotypes in a population are also common in the most similar HapMap sample. Consequently, although the portability of tag SNPs based on the HapMap is reduced in low-LD Africans, the HapMap will be helpful for the design of genome-wide association mapping studies in nearly all human populations. 相似文献
118.
Graham RR Kozyrev SV Baechler EC Reddy MV Plenge RM Bauer JW Ortmann WA Koeuth T González Escribano MF;Argentine Spanish Collaborative Groups Pons-Estel B Petri M Daly M Gregersen PK Martín J Altshuler D Behrens TW Alarcón-Riquelme ME 《Nature genetics》2006,38(5):550-555
Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by activation of the type I interferon (IFN) pathway. Here we convincingly replicate association of the IFN regulatory factor 5 (IRF5) rs2004640 T allele with SLE in four independent case-control cohorts (P = 4.4 x 10(-16)) and by family-based transmission disequilibrium test analysis (P = 0.0006). The rs2004640 T allele creates a 5' donor splice site in an alternate exon 1 of IRF5, allowing expression of several unique IRF5 isoforms. We also identify an independent cis-acting variant associated with elevated expression of IRF5 and linked to the exon 1B splice site. Haplotypes carrying the variant associated with elevated expression and lacking the exon 1B donor site do not confer risk of SLE. Thus, a common IRF5 haplotype driving elevated expression of multiple unique isoforms of IRF5 is an important genetic risk factor for SLE, establishing a causal role for type I IFN pathway genes in human autoimmunity. 相似文献
119.
Germline mutations in DIS3L2 cause the Perlman syndrome of overgrowth and Wilms tumor susceptibility
Astuti D Morris MR Cooper WN Staals RH Wake NC Fews GA Gill H Gentle D Shuib S Ricketts CJ Cole T van Essen AJ van Lingen RA Neri G Opitz JM Rump P Stolte-Dijkstra I Müller F Pruijn GJ Latif F Maher ER 《Nature genetics》2012,44(3):277-284
Perlman syndrome is a congenital overgrowth syndrome inherited in an autosomal recessive manner that is associated with Wilms tumor susceptibility. We mapped a previously unknown susceptibility locus to 2q37.1 and identified germline mutations in DIS3L2, a homolog of the Schizosaccharomyces pombe dis3 gene, in individuals with Perlman syndrome. Yeast dis3 mutant strains have mitotic abnormalities. Yeast Dis3 and its human homologs, DIS3 and DIS3L1, have exoribonuclease activity and bind to the core RNA exosome complex. DIS3L2 has a different intracellular localization and lacks the PIN domain found in DIS3 and DIS3L1; nevertheless, we show that DIS3L2 has exonuclease activity. DIS3L2 inactivation was associated with mitotic abnormalities and altered expression of mitotic checkpoint proteins. DIS3L2 overexpression suppressed the growth of human cancer cell lines, and knockdown enhanced the growth of these cells. We also detected evidence of DIS3L2 mutations in sporadic Wilms tumor. These observations suggest that DIS3L2 has a critical role in RNA metabolism and is essential for the regulation of cell growth and division. 相似文献