1会议背景和基本情况
发展中国家科学院（The Academy of Sciences for the Developing World, TWAS）成立于1983年11月，总部设在意大利的里雅斯特，是一个非政府、非政治和非营利性的国际科学组织，旨在促进发展中国家的科技发展，...1会议背景和基本情况
发展中国家科学院（The Academy of Sciences for the Developing World, TWAS）成立于1983年11月，总部设在意大利的里雅斯特，是一个非政府、非政治和非营利性的国际科学组织，旨在促进发展中国家的科技发展，支持发展中国家科技人员和科研机构之间的交流与合作。TWAS每年举行一次院士大会，每2—3年举行一次学术研讨会。TWAS历届会议均得到主办国政府的高度重视，中国在1987年和2003年成功地举办了第2届和第14届院士大会。展开更多
Background A detailed understanding of genetic variants that affect beef merit helps maximize the efficiency of breeding for improved production merit in beef cattle.To prioritize the putative variants and genes,we ra...Background A detailed understanding of genetic variants that affect beef merit helps maximize the efficiency of breeding for improved production merit in beef cattle.To prioritize the putative variants and genes,we ran a com-prehensive genome-wide association studies(GWAS)analysis for 21 agronomic traits using imputed whole-genome variants in Simmental beef cattle.Then,we applied expression quantitative trait loci(eQTL)mapping between the genotype variants and transcriptome of three tissues(longissimus dorsi muscle,backfat,and liver)in 120 cattle.Results We identified 1,580 association signals for 21 beef agronomic traits using GWAS.We then illuminated 854,498 cis-eQTLs for 6,017 genes and 46,970 trans-eQTLs for 1,903 genes in three tissues and built a synergistic network by integrating transcriptomics with agronomic traits.These cis-eQTLs were preferentially close to the transcription start site and enriched in functional regulatory regions.We observed an average of 43.5%improvement in cis-eQTL discovery using multi-tissue eQTL mapping.Fine-mapping analysis revealed that 111,192,and 194 variants were most likely to be causative to regulate gene expression in backfat,liver,and muscle,respectively.The transcriptome-wide association studies identified 722 genes significantly associated with 11 agronomic traits.Via the colocalization and Mendelian randomization analyses,we found that eQTLs of several genes were associated with the GWAS signals of agronomic traits in three tissues,which included genes,such as NADSYN1,NDUFS3,LTF and KIFC2 in liver,GRAMD1C,TMTC2 and ZNF613 in backfat,as well as TIGAR,NDUFS3 and L3HYPDH in muscle that could serve as the candidate genes for economic traits.Conclusions The extensive atlas of GWAS,eQTL,fine-mapping,and transcriptome-wide association studies aid in the suggestion of potentially functional variants and genes in cattle agronomic traits and will be an invaluable source for genomics and breeding in beef cattle.展开更多
Thermal sprayed Ni-20wt. % Al coating is fabricated on 6061-T6 aluminum alloy substrates by twin-wire arc spraying （TWAS）. Experimental results present that the average bonding strength is around 53 MPa and the aver...Thermal sprayed Ni-20wt. % Al coating is fabricated on 6061-T6 aluminum alloy substrates by twin-wire arc spraying （TWAS）. Experimental results present that the average bonding strength is around 53 MPa and the average hardness reaches 325 HV. The Vickers microhardness of NiAl and Ni3Al intermetaUic compounds is larger than that of the substrate, which is beneficial for improving the wear property. Wear mechanism exhibits features of adhesive wear. Friction and wear test results indicate that the wet friction coefficient is higher than the coefficient of dry friction after 200 cycles, and variations of the wet friction coefficient are relatively smaller.展开更多
Seed oil content(SOC)is a highly important and complex trait in oil crops.Here,we decipher the genetic basis of natural variation in SOC of Brassica napus by genome-and transcriptome-wide association studies using 505...Seed oil content(SOC)is a highly important and complex trait in oil crops.Here,we decipher the genetic basis of natural variation in SOC of Brassica napus by genome-and transcriptome-wide association studies using 505 inbred lines.We mapped reliable quantitative trait loci(QTLs)that control SOC in eight environments,evaluated the effect of each QTL on SOC,and analyzed selection in QTL regions during breeding.Six-hundred and ninety-two genes and four gene modules significantly associated with SOC were identified by analyzing population transcriptomes from seeds.A gene prioritization framework,POCKET(prioritizing the candidate genes by incorporating information on knowledge-based gene sets,effects of variants,genome-wide association studies,and transcriptome-wide association studies),was implemented to determine the causal genes in the QTL regions based on multi-omic datasets.A pair of homologous genes,BnPMT6s,in two QTLs were identified and experimentally demonstrated to negatively regulate SOC.This study provides rich genetic resources for improving SOC and valuable insights toward understanding the complex machinery that directs oil accumulation in the seeds of B.napus and other oil crops.展开更多
Background:Genome wide association studies(GWAS)have identified many genetic variants associated with increased risk of Alzheimer^disease(AD).These susceptibility loci may effect AD indirectly through a combination of...Background:Genome wide association studies(GWAS)have identified many genetic variants associated with increased risk of Alzheimer^disease(AD).These susceptibility loci may effect AD indirectly through a combination of physiological brain changes.Many of these neuropathologic features are detectable via magnetic resonance imaging(MRI).Methods:In this study,we examine the effects of such brain imaging derived phenotypes(IDPs)with genetic etiology on AD,using and comparing the following methods:two-sample Mendelian randomization(2SMR),generalized summary statistics based Mendelian randomization(GSMR),transcriptome wide association studies(TWAS)and the adaptive sum of powered score(aSPU)test.These methods do not require individual-level genotypic and phenotypic data but instead can rely only on an external reference panel and GWAS summary statistics.Results:Using publicly available GWAS datasets from the International Genomics of Alzheimer's Project(IGAP)and UK Biobank's(UKBB)brain imaging initiatives,we identify 35 IDPs possibly associated with AD,many of which have well established or biologically plausible links to the characteristic cognitive impairments of this neurodegenerative disease.Conclusions:Our results highlight the increased power for detecting genetic associations achieved by multiple correlated SNP-based methods,i.e.,aSPU,GSMR and TWAS,over MR methods based on independent SNPs(as instrumental variables).展开更多
Background:Genome-wide association studies(GWAS)have succeeded in identifying tens of thousands of genetic variants associated with complex human traits during the past decade,however,they are still hampered by limite...Background:Genome-wide association studies(GWAS)have succeeded in identifying tens of thousands of genetic variants associated with complex human traits during the past decade,however,they are still hampered by limited statistical power and difficulties in biological interpretation.With the recent progress in expression quantitative trait loci(eQTL)studies,transcriptome-wide association studies(TWAS)provide a framework to test for gene-trait associations by integrating information from GWAS and eQTL studies.Results:In this review,we will introduce the general framework of TWAS,the relevant resources,and the computational tools.Extensions of the original TWAS methods will also be discussed.Furthermore,we will briefly introduce methods that are closely related to TWAS,including MR-based methods and colocalization approaches.Connection and difference between these approaches will be discussed.Conclusion:Finally,we will summarize strengths,limitations,and potential directions for TWAS.展开更多
文摘1会议背景和基本情况
发展中国家科学院（The Academy of Sciences for the Developing World, TWAS）成立于1983年11月，总部设在意大利的里雅斯特，是一个非政府、非政治和非营利性的国际科学组织，旨在促进发展中国家的科技发展，支持发展中国家科技人员和科研机构之间的交流与合作。TWAS每年举行一次院士大会，每2—3年举行一次学术研讨会。TWAS历届会议均得到主办国政府的高度重视，中国在1987年和2003年成功地举办了第2届和第14届院士大会。
基金supported by grants from the Central Public-interest Scientific Institution Basal Research Fund(2020-YWF-YB-02)the Young Scientists Fund of the National Natural Science Foundation of China(32202652)+1 种基金China Agriculture Research System of MOF and MARA(CARS-37)the Science and Technology Project of Inner Mongolia Autonomous Region(2020GG0210).
文摘Background A detailed understanding of genetic variants that affect beef merit helps maximize the efficiency of breeding for improved production merit in beef cattle.To prioritize the putative variants and genes,we ran a com-prehensive genome-wide association studies(GWAS)analysis for 21 agronomic traits using imputed whole-genome variants in Simmental beef cattle.Then,we applied expression quantitative trait loci(eQTL)mapping between the genotype variants and transcriptome of three tissues(longissimus dorsi muscle,backfat,and liver)in 120 cattle.Results We identified 1,580 association signals for 21 beef agronomic traits using GWAS.We then illuminated 854,498 cis-eQTLs for 6,017 genes and 46,970 trans-eQTLs for 1,903 genes in three tissues and built a synergistic network by integrating transcriptomics with agronomic traits.These cis-eQTLs were preferentially close to the transcription start site and enriched in functional regulatory regions.We observed an average of 43.5%improvement in cis-eQTL discovery using multi-tissue eQTL mapping.Fine-mapping analysis revealed that 111,192,and 194 variants were most likely to be causative to regulate gene expression in backfat,liver,and muscle,respectively.The transcriptome-wide association studies identified 722 genes significantly associated with 11 agronomic traits.Via the colocalization and Mendelian randomization analyses,we found that eQTLs of several genes were associated with the GWAS signals of agronomic traits in three tissues,which included genes,such as NADSYN1,NDUFS3,LTF and KIFC2 in liver,GRAMD1C,TMTC2 and ZNF613 in backfat,as well as TIGAR,NDUFS3 and L3HYPDH in muscle that could serve as the candidate genes for economic traits.Conclusions The extensive atlas of GWAS,eQTL,fine-mapping,and transcriptome-wide association studies aid in the suggestion of potentially functional variants and genes in cattle agronomic traits and will be an invaluable source for genomics and breeding in beef cattle.
文摘Thermal sprayed Ni-20wt. % Al coating is fabricated on 6061-T6 aluminum alloy substrates by twin-wire arc spraying （TWAS）. Experimental results present that the average bonding strength is around 53 MPa and the average hardness reaches 325 HV. The Vickers microhardness of NiAl and Ni3Al intermetaUic compounds is larger than that of the substrate, which is beneficial for improving the wear property. Wear mechanism exhibits features of adhesive wear. Friction and wear test results indicate that the wet friction coefficient is higher than the coefficient of dry friction after 200 cycles, and variations of the wet friction coefficient are relatively smaller.
基金This study was supported by the National Key Research and Development Plan of China(2016YFD0101000,2017YFE0104800)the National Natural Science Foundation of China(32070559,31871658).
文摘Seed oil content(SOC)is a highly important and complex trait in oil crops.Here,we decipher the genetic basis of natural variation in SOC of Brassica napus by genome-and transcriptome-wide association studies using 505 inbred lines.We mapped reliable quantitative trait loci(QTLs)that control SOC in eight environments,evaluated the effect of each QTL on SOC,and analyzed selection in QTL regions during breeding.Six-hundred and ninety-two genes and four gene modules significantly associated with SOC were identified by analyzing population transcriptomes from seeds.A gene prioritization framework,POCKET(prioritizing the candidate genes by incorporating information on knowledge-based gene sets,effects of variants,genome-wide association studies,and transcriptome-wide association studies),was implemented to determine the causal genes in the QTL regions based on multi-omic datasets.A pair of homologous genes,BnPMT6s,in two QTLs were identified and experimentally demonstrated to negatively regulate SOC.This study provides rich genetic resources for improving SOC and valuable insights toward understanding the complex machinery that directs oil accumulation in the seeds of B.napus and other oil crops.
基金NIH grants T32GM108557,R01AG065636,R01HL116720,R01GM113250 and R01GM126002by the Minnesota Supercomputing Institute at the University of Minnesota.
文摘Background:Genome wide association studies(GWAS)have identified many genetic variants associated with increased risk of Alzheimer^disease(AD).These susceptibility loci may effect AD indirectly through a combination of physiological brain changes.Many of these neuropathologic features are detectable via magnetic resonance imaging(MRI).Methods:In this study,we examine the effects of such brain imaging derived phenotypes(IDPs)with genetic etiology on AD,using and comparing the following methods:two-sample Mendelian randomization(2SMR),generalized summary statistics based Mendelian randomization(GSMR),transcriptome wide association studies(TWAS)and the adaptive sum of powered score(aSPU)test.These methods do not require individual-level genotypic and phenotypic data but instead can rely only on an external reference panel and GWAS summary statistics.Results:Using publicly available GWAS datasets from the International Genomics of Alzheimer's Project(IGAP)and UK Biobank's(UKBB)brain imaging initiatives,we identify 35 IDPs possibly associated with AD,many of which have well established or biologically plausible links to the characteristic cognitive impairments of this neurodegenerative disease.Conclusions:Our results highlight the increased power for detecting genetic associations achieved by multiple correlated SNP-based methods,i.e.,aSPU,GSMR and TWAS,over MR methods based on independent SNPs(as instrumental variables).
基金National Natural Science Foundation of China(No.11601259)Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX01).Y.X.and N.S.were supported in part by the China Scholarship Council,and H.Z.was supported in part by NIH grant R01GM122078,NSF grants DMS 1713120 and DMS 1902903.
文摘Background:Genome-wide association studies(GWAS)have succeeded in identifying tens of thousands of genetic variants associated with complex human traits during the past decade,however,they are still hampered by limited statistical power and difficulties in biological interpretation.With the recent progress in expression quantitative trait loci(eQTL)studies,transcriptome-wide association studies(TWAS)provide a framework to test for gene-trait associations by integrating information from GWAS and eQTL studies.Results:In this review,we will introduce the general framework of TWAS,the relevant resources,and the computational tools.Extensions of the original TWAS methods will also be discussed.Furthermore,we will briefly introduce methods that are closely related to TWAS,including MR-based methods and colocalization approaches.Connection and difference between these approaches will be discussed.Conclusion:Finally,we will summarize strengths,limitations,and potential directions for TWAS.
