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61.
A Martin-Gallardo W R McCombie J D Gocayne M G FitzGerald S Wallace B M Lee J Lamerdin S Trapp J M Kelley L I Liu 《Nature genetics》1992,1(1):34-39
A total of 116,118 basepairs (bp) derived from three cosmids spanning the ERCC1 locus of human chromosome 19q13.3 have been sequenced with automated fluorescence-based sequencers and analysed by polymerase chain reaction amplification and computer methods. The assembled sequence forms two contigs totalling 105,831 bp, which contain a human fosB proto-oncogene, a gene encoding a protein phosphatase, two genes of unknown function and the previously-characterized ERCC1 DNA repair gene. This light band region has a high average density of 1.4 Alu repeats per kilobase. Human chromosome light bands could therefore contain up to 75,000 genes and 1.5 million Alu repeats. 相似文献
62.
63.
Integrated transcriptional profiling and linkage analysis for identification of genes underlying disease 总被引:22,自引:0,他引:22
Hubner N Wallace CA Zimdahl H Petretto E Schulz H Maciver F Mueller M Hummel O Monti J Zidek V Musilova A Kren V Causton H Game L Born G Schmidt S Müller A Cook SA Kurtz TW Whittaker J Pravenec M Aitman TJ 《Nature genetics》2005,37(3):243-253
Integration of genome-wide expression profiling with linkage analysis is a new approach to identifying genes underlying complex traits. We applied this approach to the regulation of gene expression in the BXH/HXB panel of rat recombinant inbred strains, one of the largest available rodent recombinant inbred panels and a leading resource for genetic analysis of the highly prevalent metabolic syndrome. In two tissues important to the pathogenesis of the metabolic syndrome, we mapped cis- and trans-regulatory control elements for expression of thousands of genes across the genome. Many of the most highly linked expression quantitative trait loci are regulated in cis, are inherited essentially as monogenic traits and are good candidate genes for previously mapped physiological quantitative trait loci in the rat. By comparative mapping we generated a data set of 73 candidate genes for hypertension that merit testing in human populations. Mining of this publicly available data set is expected to lead to new insights into the genes and regulatory pathways underlying the extensive range of metabolic and cardiovascular disease phenotypes that segregate in these recombinant inbred strains. 相似文献
64.
Prolonged suppression of ecosystem carbon dioxide uptake after an anomalously warm year 总被引:2,自引:0,他引:2
Arnone JA Verburg PS Johnson DW Larsen JD Jasoni RL Lucchesi AJ Batts CM von Nagy C Coulombe WG Schorran DE Buck PE Braswell BH Coleman JS Sherry RA Wallace LL Luo Y Schimel DS 《Nature》2008,455(7211):383-386
Terrestrial ecosystems control carbon dioxide fluxes to and from the atmosphere through photosynthesis and respiration, a balance between net primary productivity and heterotrophic respiration, that determines whether an ecosystem is sequestering carbon or releasing it to the atmosphere. Global and site-specific data sets have demonstrated that climate and climate variability influence biogeochemical processes that determine net ecosystem carbon dioxide exchange (NEE) at multiple timescales. Experimental data necessary to quantify impacts of a single climate variable, such as temperature anomalies, on NEE and carbon sequestration of ecosystems at interannual timescales have been lacking. This derives from an inability of field studies to avoid the confounding effects of natural intra-annual and interannual variability in temperature and precipitation. Here we present results from a four-year study using replicate 12,000-kg intact tallgrass prairie monoliths located in four 184-m(3) enclosed lysimeters. We exposed 6 of 12 monoliths to an anomalously warm year in the second year of the study and continuously quantified rates of ecosystem processes, including NEE. We find that warming decreases NEE in both the extreme year and the following year by inducing drought that suppresses net primary productivity in the extreme year and by stimulating heterotrophic respiration of soil biota in the subsequent year. Our data indicate that two years are required for NEE in the previously warmed experimental ecosystems to recover to levels measured in the control ecosystems. This time lag caused net ecosystem carbon sequestration in previously warmed ecosystems to be decreased threefold over the study period, compared with control ecosystems. Our findings suggest that more frequent anomalously warm years, a possible consequence of increasing anthropogenic carbon dioxide levels, may lead to a sustained decrease in carbon dioxide uptake by terrestrial ecosystems. 相似文献
65.
Leaf litter accumulation during fire exclusion and increases in tree density in postsettlement southwestern Pinus ponderosa forests may limit the establishment of understory vegetation. We performed an experiment in P. ponderosa forests of northern Arizona to ascertain plant community responses to forest-floor scarification and Oi removal on thirty-six 100-m 2 plots overlaid on an existing ecological restoration experiment that involved tree thinning and prescribed burning. Constrasting with findings from many other forest types, forest-floor treatments had no effect on community diversity or composition during the 2-year experiment. S?rensen similarities were as high as 97% between posttreatment years within treatments; and successional vectors also provided little indication that treatments may appreciably affect longer-term successional trajectories. Lack of response to these fairly drastic treatments is surprising given these forests' exceptionally heavy Oi horizons and large proportions of conifer litter. Apparently shading, belowground competition for water or nutrients, or other tree-associated factors more strongly limit understory communities than does leaf litter. Based on sparse A-horizon seed banks averaging <300 seeds ? m –2 and limited aboveground vegetation, we hypothesize that seed shortages, particularly for native perennials, also partly precluded a treatment response. Because extensive unvegetated areas at these restoration sites may be colonized by exotics, conservative management strategies could include testing the seeding or outplanting of desirable native species as an option for filling unoccupied microsites. Reporting of "no treatment effect" experiments such as this one is important to avoid biasing meta-analyses, as is future research to clarify combinations of factors limiting understory communities. Increased understanding of these limiting factors may lead to identification of other treatments that promote recovery of native species during ecological restoration in this region. 相似文献
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67.
New county records are reported for Hypsiglena torquata and Rhinocheilus lecontci, and additional distribution records are presented for Sonora semiannulata in southwestern Idaho. These three species are more abundant than indicated by previous records. 相似文献
68.
David Wallace 《Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics》2009,40(3):209-222
A systematic analysis is made of the relations between the symmetries of a classical field and the symmetries of the one-particle quantum system that results from quantizing that field in regimes where interactions are weak. The results are applied to gain a greater insight into the phenomenon of antimatter. 相似文献
69.
Painter JN Anderson CA Nyholt DR Macgregor S Lin J Lee SH Lambert A Zhao ZZ Roseman F Guo Q Gordon SD Wallace L Henders AK Visscher PM Kraft P Martin NG Morris AP Treloar SA Kennedy SH Missmer SA Montgomery GW Zondervan KT 《Nature genetics》2011,43(1):51-54
Endometriosis is a common gynecological disease associated with pelvic pain and subfertility. We conducted a genome-wide association study (GWAS) in 3,194 individuals with surgically confirmed endometriosis (cases) and 7,060 controls from Australia and the UK. Polygenic predictive modeling showed significantly increased genetic loading among 1,364 cases with moderate to severe endometriosis. The strongest association signal was on 7p15.2 (rs12700667) for 'all' endometriosis (P = 2.6 × 10??, odds ratio (OR) = 1.22, 95% CI 1.13-1.32) and for moderate to severe disease (P = 1.5 × 10??, OR = 1.38, 95% CI 1.24-1.53). We replicated rs12700667 in an independent cohort from the United States of 2,392 self-reported, surgically confirmed endometriosis cases and 2,271 controls (P = 1.2 × 10?3, OR = 1.17, 95% CI 1.06-1.28), resulting in a genome-wide significant P value of 1.4 × 10?? (OR = 1.20, 95% CI 1.13-1.27) for 'all' endometriosis in our combined datasets of 5,586 cases and 9,331 controls. rs12700667 is located in an intergenic region upstream of the plausible candidate genes NFE2L3 and HOXA10. 相似文献
70.
Jin Y Birlea SA Fain PR Ferrara TM Ben S Riccardi SL Cole JB Gowan K Holland PJ Bennett DC Luiten RM Wolkerstorfer A van der Veen JP Hartmann A Eichner S Schuler G van Geel N Lambert J Kemp EH Gawkrodger DJ Weetman AP Taïeb A Jouary T Ezzedine K Wallace MR McCormack WT Picardo M Leone G Overbeck A Silverberg NB Spritz RA 《Nature genetics》2012,44(6):676-680
We previously reported a genome-wide association study (GWAS) identifying 14 susceptibility loci for generalized vitiligo. We report here a second GWAS (450 individuals with vitiligo (cases) and 3,182 controls), an independent replication study (1,440 cases and 1,316 controls) and a meta-analysis (3,187 cases and 6,723 controls) identifying 13 additional vitiligo-associated loci. These include OCA2-HERC2 (combined P = 3.80 × 10(-8)), MC1R (P = 1.82 × 10(-13)), a region near TYR (P = 1.57 × 10(-13)), IFIH1 (P = 4.91 × 10(-15)), CD80 (P = 3.78 × 10(-10)), CLNK (P = 1.56 × 10(-8)), BACH2 (P = 2.53 × 10(-8)), SLA (P = 1.58 × 10(-8)), CASP7 (P = 3.56 × 10(-8)), CD44 (P = 1.78 × 10(-9)), IKZF4 (P = 2.75 × 10(-14)), SH2B3 (P = 3.54 × 10(-18)) and TOB2 (P = 6.81 × 10(-10)). Most vitiligo susceptibility loci encode immunoregulatory proteins or melanocyte components that likely mediate immune targeting and the relationships among vitiligo, melanoma, and eye, skin and hair coloration. 相似文献