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201.
202.
Dense genotyping identifies and localizes multiple common and rare variant association signals in celiac disease 总被引:1,自引:0,他引:1
Trynka G Hunt KA Bockett NA Romanos J Mistry V Szperl A Bakker SF Bardella MT Bhaw-Rosun L Castillejo G de la Concha EG de Almeida RC Dias KR van Diemen CC Dubois PC Duerr RH Edkins S Franke L Fransen K Gutierrez J Heap GA Hrdlickova B Hunt S Izurieta LP Izzo V Joosten LA Langford C Mazzilli MC Mein CA Midah V Mitrovic M Mora B Morelli M Nutland S Núñez C Onengut-Gumuscu S Pearce K Platteel M Polanco I Potter S Ribes-Koninckx C Ricaño-Ponce I Rich SS Rybak A Santiago JL Senapati S Sood A 《Nature genetics》2011,43(12):1193-1201
Using variants from the 1000 Genomes Project pilot European CEU dataset and data from additional resequencing studies, we densely genotyped 183 non-HLA risk loci previously associated with immune-mediated diseases in 12,041 individuals with celiac disease (cases) and 12,228 controls. We identified 13 new celiac disease risk loci reaching genome-wide significance, bringing the number of known loci (including the HLA locus) to 40. We found multiple independent association signals at over one-third of these loci, a finding that is attributable to a combination of common, low-frequency and rare genetic variants. Compared to previously available data such as those from HapMap3, our dense genotyping in a large sample collection provided a higher resolution of the pattern of linkage disequilibrium and suggested localization of many signals to finer scale regions. In particular, 29 of the 54 fine-mapped signals seemed to be localized to single genes and, in some instances, to gene regulatory elements. Altogether, we define the complex genetic architecture of the risk regions of and refine the risk signals for celiac disease, providing the next step toward uncovering the causal mechanisms of the disease. 相似文献
203.
Hahn CN Chong CE Carmichael CL Wilkins EJ Brautigan PJ Li XC Babic M Lin M Carmagnac A Lee YK Kok CH Gagliardi L Friend KL Ekert PG Butcher CM Brown AL Lewis ID To LB Timms AE Storek J Moore S Altree M Escher R Bardy PG Suthers GK D'Andrea RJ Horwitz MS Scott HS 《Nature genetics》2011,43(10):1012-1017
204.
Peter J. Perkins Frederick G. Lindzey Jay A. Roberson Gregory McDaniel Randy Berger 《西北部美国博物学家》2011,49(2)
Winter habitat use and food habits of Blue Grouse ( Dendragapus obscurus ) were studied in an isolated Utah desert mountain range that contained little typical Douglas-fir ( Pseudotsuga menziesii ) winter habitat. Habitat use was concentrated in the Douglas-fir and pinyon ( Pinus edulis )-juniper ( Juniperus spp. ) habitat. Douglas-fir and pinyon pine were the most consumed foods. Other foods that represented >15% of the composition of an individual fecal sample were limber pine ( Pinus flexilis ), mahogany ( Cercocarpus ledifoliu ), juniper, and an Anteunaria-Cirsium type. The breadth in winter diet indicates that Blue Grouse may successfully occupy other habitats when typical winter habitat is scarce. 相似文献
205.
Based on a sample of 17 adult specimens of Sceloporus horridus taken near Autlan, Jalisco, Mexico in May 1974 just before and just after the first rainfall of the year, we present the first published data on the food habits of this lizard. Important prey item taxa were Homoptera, Coleoptera, Hymenoptera, Orthoptera, and Isoptera. The absence of Homoptera and Orthoptera, and the concomitant greater relative importance of Isoptera and Hymenoptera in the diet after the rain than before indicates opportunistic feeding by S. horridus. Our data suggest that reproduction in this lizard is probably initiated soon after the first rains in late spring. 相似文献
206.
The floristic composition of Navajo National Monument is presented. The flora of the monument consists of 293 species of vascular plants, representing 177 genera and 66 families. The species are scattered throughout 12 plant communities found within the monument. The flora is dominated by forbs (60 percent), followed by shrubs (16 percent), grasses (12 percent) and trees (5 percent). Betatakin canyon exhibits the greatest floristic richness with 223 species being represented and 123 species found only in that area. This is due primarily to two factors: (1) the greater variety of habitats available in the area, and (2) the much longer time the area has been protected from grazing and other manmade disturbance. 相似文献
207.
Patterns of colonization by macroinvertebrates were examined in two streams that differ in flow regime: a snowmelt system and a mesic groundwater system. Experiments were conducted during spring runoff, summer baseflow, and winter baseflow using artificial substrata. Colonization patterns reflected seasonal changes in benthic macroinvertebrate assemblages and life histories in each stream. The density and biomass of benthic organisms were approximately 3X greater in winter than in either spring or summer for both streams. Similarly, colonization was greater in winter than in spring or summer for both streams. In spring, colonization patterns were different between streams, with colonization being imperceptible in the snowmelt stream. Macroinvertebrate abundance fluctuated during the summer colonization experiment at both sites, resulting from a complex interplay among population emergence, recruitment, and/or movement. Assemblages in the snowmelt system primarily comprised mobile or ruderal taxa, such as Beatis tricaudatus and Chironomidae, whereas relatively sessile taxa, such as Glossoma nigrior , were predominant in the mesic groundwater system. Seasonal patterns of colonization differed among stream types primarily because of the profound interplay of flow regime and temperature on benthic community structure and organism life history. 相似文献
208.
Whole-genome sequences provide a rich source of information about human evolution. Here we describe an effort to estimate key evolutionary parameters based on the whole-genome sequences of six individuals from diverse human populations. We used a Bayesian, coalescent-based approach to obtain information about ancestral population sizes, divergence times and migration rates from inferred genealogies at many neutrally evolving loci across the genome. We introduce new methods for accommodating gene flow between populations and integrating over possible phasings of diploid genotypes. We also describe a custom pipeline for genotype inference to mitigate biases from heterogeneous sequencing technologies and coverage levels. Our analysis indicates that the San population of southern Africa diverged from other human populations approximately 108-157 thousand years ago, that Eurasians diverged from an ancestral African population 38-64 thousand years ago, and that the effective population size of the ancestors of all modern humans was ~9,000. 相似文献
209.
Common variants at MS4A4/MS4A6E, CD2AP, CD33 and EPHA1 are associated with late-onset Alzheimer's disease 总被引:1,自引:0,他引:1
Naj AC Jun G Beecham GW Wang LS Vardarajan BN Buros J Gallins PJ Buxbaum JD Jarvik GP Crane PK Larson EB Bird TD Boeve BF Graff-Radford NR De Jager PL Evans D Schneider JA Carrasquillo MM Ertekin-Taner N Younkin SG Cruchaga C Kauwe JS Nowotny P Kramer P Hardy J Huentelman MJ Myers AJ Barmada MM Demirci FY Baldwin CT Green RC Rogaeva E St George-Hyslop P Arnold SE Barber R Beach T Bigio EH Bowen JD Boxer A Burke JR Cairns NJ Carlson CS Carney RM Carroll SL Chui HC Clark DG Corneveaux J Cotman CW 《Nature genetics》2011,43(5):436-441
The Alzheimer Disease Genetics Consortium (ADGC) performed a genome-wide association study of late-onset Alzheimer disease using a three-stage design consisting of a discovery stage (stage 1) and two replication stages (stages 2 and 3). Both joint analysis and meta-analysis approaches were used. We obtained genome-wide significant results at MS4A4A (rs4938933; stages 1 and 2, meta-analysis P (P(M)) = 1.7 × 10(-9), joint analysis P (P(J)) = 1.7 × 10(-9); stages 1, 2 and 3, P(M) = 8.2 × 10(-12)), CD2AP (rs9349407; stages 1, 2 and 3, P(M) = 8.6 × 10(-9)), EPHA1 (rs11767557; stages 1, 2 and 3, P(M) = 6.0 × 10(-10)) and CD33 (rs3865444; stages 1, 2 and 3, P(M) = 1.6 × 10(-9)). We also replicated previous associations at CR1 (rs6701713; P(M) = 4.6 × 10(-10), P(J) = 5.2 × 10(-11)), CLU (rs1532278; P(M) = 8.3 × 10(-8), P(J) = 1.9 × 10(-8)), BIN1 (rs7561528; P(M) = 4.0 × 10(-14), P(J) = 5.2 × 10(-14)) and PICALM (rs561655; P(M) = 7.0 × 10(-11), P(J) = 1.0 × 10(-10)), but not at EXOC3L2, to late-onset Alzheimer's disease susceptibility. 相似文献
210.
Schramek D Kotsinas A Meixner A Wada T Elling U Pospisilik JA Neely GG Zwick RH Sigl V Forni G Serrano M Gorgoulis VG Penninger JM 《Nature genetics》2011,43(3):212-219
Most preneoplastic lesions are quiescent and do not progress to form overt tumors. It has been proposed that oncogenic stress activates the DNA damage response and the key tumor suppressor p53, which prohibits tumor growth. However, the molecular pathways by which cells sense a premalignant state in vivo are largely unknown. Here we report that tissue-specific inactivation of the stress signaling kinase MKK7 in KRas(G12D)-driven lung carcinomas and NeuT-driven mammary tumors markedly accelerates tumor onset and reduces overall survival. Mechanistically, MKK7 acts through the kinases JNK1 and JNK2, and this signaling pathway directly couples oncogenic and genotoxic stress to the stability of p53, which is required for cell cycle arrest and suppression of epithelial cancers. These results show that MKK7 functions as a major tumor suppressor in lung and mammary cancer in mouse and identify MKK7 as a vital molecular sensor to set a cellular anti-cancer barrier. 相似文献