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排序方式: 共有177条查询结果,搜索用时 15 毫秒
141.
Tamara Luciane de Souza Silva Machado Vitor Torga Lombardi Ricardo Camargos de Meireles João Paulo Gusmão Teixeira Ricardo R. de C. Solar 《Journal of Natural History》2017,51(41-42):2551-2563
The Campo Miner is a threatened grassland passerine endemic to the South American Cerrado, whose life history is almost unknown. In this paper, we studied during three breeding seasons (2014 to 2016) the breeding biology of a colour banded population of the species found in the Upper Rio Grande Grasslands, south-eastern Brazil. We found 98 nests, 81 of which became active and were monitored. The Campo Miner breeds in frequently burnt-and-grazed natural grasslands, successfully nesting in highly disturbed sites, such as dirt banks along roads and even in mine pits. The species is socially monogamous and both parents build the nest, which is a cavity/with-tunnel/simple/platform type. The nest chamber is lined with a platform made of grass fragments, charcoal, hairs, and mammal faeces. The most common clutch size is three eggs (n = 66), with some nests containing one (n = 1), two (n = 12) or four eggs (n = 2). The egg is white and pyriform and the incubation, performed by both parents, lasts 17.5 days. Mean nestling period is 15.5 days, with both parents feeding the young. Breeding season lasted for about 125 days (August to December) and multiple breeding attempts in a single season were common, with a maximum of three attempts recorded. All species of Scleruridae built their nests inside cavities dug in the soil with an access tunnel to it, where they lay a small clutch (usually 2–3 white eggs), but no other species in the family has been studied in detail to date. Further studies are required to understand why a species apparently tolerant to anthropogenic impacts such as G. poeciloptera can be so rare, patchily distributed and threatened throughout its range. 相似文献
142.
Dunlop MG Dobbins SE Farrington SM Jones AM Palles C Whiffin N Tenesa A Spain S Broderick P Ooi LY Domingo E Smillie C Henrion M Frampton M Martin L Grimes G Gorman M Semple C Ma YP Barclay E Prendergast J Cazier JB Olver B Penegar S Lubbe S Chander I Carvajal-Carmona LG Ballereau S Lloyd A Vijayakrishnan J Zgaga L Rudan I Theodoratou E;Colorectal Tumour Gene Identification 《Nature genetics》2012,44(7):770-776
We performed a meta-analysis of five genome-wide association studies to identify common variants influencing colorectal cancer (CRC) risk comprising 8,682 cases and 9,649 controls. Replication analysis was performed in case-control sets totaling 21,096 cases and 19,555 controls. We identified three new CRC risk loci at 6p21 (rs1321311, near CDKN1A; P = 1.14 × 10(-10)), 11q13.4 (rs3824999, intronic to POLD3; P = 3.65 × 10(-10)) and Xp22.2 (rs5934683, near SHROOM2; P = 7.30 × 10(-10)) This brings the number of independent loci associated with CRC risk to 20 and provides further insight into the genetic architecture of inherited susceptibility to CRC. 相似文献
143.
Mutations in SLC20A2 link familial idiopathic basal ganglia calcification with phosphate homeostasis
Wang C Li Y Shi L Ren J Patti M Wang T de Oliveira JR Sobrido MJ Quintáns B Baquero M Cui X Zhang XY Wang L Xu H Wang J Yao J Dai X Liu J Zhang L Ma H Gao Y Ma X Feng S Liu M Wang QK Forster IC Zhang X Liu JY 《Nature genetics》2012,44(3):254-256
Familial idiopathic basal ganglia calcification (IBGC) is a genetic condition with a wide spectrum of neuropsychiatric symptoms, including parkinsonism and dementia. Here, we identified mutations in SLC20A2, encoding the type III sodium-dependent phosphate transporter 2 (PiT2), in IBGC-affected families of varied ancestry, and we observed significantly impaired phosphate transport activity for all assayed PiT2 mutants in Xenopus laevis oocytes. Our results implicate altered phosphate homeostasis in the etiology of IBGC. 相似文献
144.
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
145.
Houlston RS Cheadle J Dobbins SE Tenesa A Jones AM Howarth K Spain SL Broderick P Domingo E Farrington S Prendergast JG Pittman AM Theodoratou E Smith CG Olver B Walther A Barnetson RA Churchman M Jaeger EE Penegar S Barclay E Martin L Gorman M Mager R Johnstone E Midgley R Niittymäki I Tuupanen S Colley J Idziaszczyk S;COGENT Consortium Thomas HJ Lucassen AM Evans DG Maher ER;CORGI Consortium;COIN Collaborative Group;COINB Collaborative Group Maughan T Dimas A Dermitzakis E Cazier JB 《Nature genetics》2010,42(11):973-977
Genome-wide association studies (GWAS) have identified ten loci harboring common variants that influence risk of developing colorectal cancer (CRC). To enhance the power to identify additional CRC risk loci, we conducted a meta-analysis of three GWAS from the UK which included a total of 3,334 affected individuals (cases) and 4,628 controls followed by multiple validation analyses including a total of 18,095 cases and 20,197 controls. We identified associations at four new CRC risk loci: 1q41 (rs6691170, odds ratio (OR) = 1.06, P = 9.55 × 10?1? and rs6687758, OR = 1.09, P = 2.27 × 10??, 3q26.2 (rs10936599, OR = 0.93, P = 3.39 × 10??), 12q13.13 (rs11169552, OR = 0.92, P = 1.89 × 10?1? and rs7136702, OR = 1.06, P = 4.02 × 10??) and 20q13.33 (rs4925386, OR = 0.93, P = 1.89 × 10?1?). In addition to identifying new CRC risk loci, this analysis provides evidence that additional CRC-associated variants of similar effect size remain to be discovered. 相似文献
146.
Scheper GC van der Klok T van Andel RJ van Berkel CG Sissler M Smet J Muravina TI Serkov SV Uziel G Bugiani M Schiffmann R Krägeloh-Mann I Smeitink JA Florentz C Van Coster R Pronk JC van der Knaap MS 《Nature genetics》2007,39(4):534-539
Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) has recently been defined based on a highly characteristic constellation of abnormalities observed by magnetic resonance imaging and spectroscopy. LBSL is an autosomal recessive disease, most often manifesting in early childhood. Affected individuals develop slowly progressive cerebellar ataxia, spasticity and dorsal column dysfunction, sometimes with a mild cognitive deficit or decline. We performed linkage mapping with microsatellite markers in LBSL families and found a candidate region on chromosome 1, which we narrowed by means of shared haplotypes. Sequencing of genes in this candidate region uncovered mutations in DARS2, which encodes mitochondrial aspartyl-tRNA synthetase, in affected individuals from all 30 families. Enzyme activities of mutant proteins were decreased. We were surprised to find that activities of mitochondrial complexes from fibroblasts and lymphoblasts derived from affected individuals were normal, as determined by different assays. 相似文献
147.
A genome-wide association scan of tag SNPs identifies a susceptibility variant for colorectal cancer at 8q24.21 总被引:16,自引:0,他引:16
Tomlinson I Webb E Carvajal-Carmona L Broderick P Kemp Z Spain S Penegar S Chandler I Gorman M Wood W Barclay E Lubbe S Martin L Sellick G Jaeger E Hubner R Wild R Rowan A Fielding S Howarth K;CORGI Consortium Silver A Atkin W Muir K Logan R Kerr D Johnstone E Sieber O Gray R Thomas H Peto J Cazier JB Houlston R 《Nature genetics》2007,39(8):984-988
Much of the variation in inherited risk of colorectal cancer (CRC) is probably due to combinations of common low risk variants. We conducted a genome-wide association study of 550,000 tag SNPs in 930 familial colorectal tumor cases and 960 controls. The most strongly associated SNP (P = 1.72 x 10(-7), allelic test) was rs6983267 at 8q24.21. To validate this finding, we genotyped rs6983267 in three additional CRC case-control series (4,361 affected individuals and 3,752 controls; 1,901 affected individuals and 1,079 controls; 1,072 affected individuals and 415 controls) and replicated the association, providing P = 1.27 x 10(-14) (allelic test) overall, with odds ratios (ORs) of 1.27 (95% confidence interval (c.i.): 1.16-1.39) and 1.47 (95% c.i.: 1.34-1.62) for heterozygotes and rare homozygotes, respectively. Analyses based on 1,477 individuals with colorectal adenoma and 2,136 controls suggest that susceptibility to CRC is mediated through development of adenomas (OR = 1.21, 95% c.i.: 1.10-1.34; P = 6.89 x 10(-5)). These data show that common, low-penetrance susceptibility alleles predispose to colorectal neoplasia. 相似文献
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