Genome-Wide Association Study Identifies Novel Candidate Genes for Aggressiveness, Deoxynivalenol Production, and Azole Sensitivity in Natural Field Populations of Fusarium graminearum

Genome-wide association studies can identify novel genomic regions and genes that affect quantitative traits. Fusarium head blight is a destructive disease caused by Fusarium graminearum that exhibits several quantitative traits, including aggressiveness, mycotoxin production, and fungicide resistance. Restriction site–associated DNA sequencing was performed for 220 isolates of F. graminearum. A total of 119 isolates were phenotyped for aggressiveness and deoxynivalenol (DON) production under natural field conditions across four environments. The effective concentration of propiconazole that inhibits isolate growth in vitro by 50% was calculated for 220 strains. Approximately 29,000 single nucleotide polymorphism markers were associated to each trait, resulting in 50, 29, and 74 quantitative trait nucleotides (QTNs) that were significantly associated to aggressiveness, DON production, and propiconazole sensitivity, respectively. Approximately 41% of these QTNs caused nonsynonymous substitutions in predicted exons, while the remainder were synonymous substitutions or located in intergenic regions. Three QTNs associated with propiconazole sensitivity were significant after Bonferroni correction. These QTNs were located in genes not previously associated with azole sensitivity. The majority of the detected QTNs were located in genes with predicted regulatory functions, suggesting that nucleotide variation in regulatory genes plays a major role in the corresponding quantitative trait variation.

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Multi-Trait Genome-Wide Association Studies Reveal Loci Associated with Maize Inflorescence and Leaf Architecture

Plant and Cell Physiology ◽

10.1093/pcp/pcaa039 ◽

2020 ◽

Vol 61 (8) ◽

pp. 1427-1437 ◽

Cited By ~ 6

Author(s):

Brian R Rice ◽

Samuel B Fernandes ◽

Alexander E Lipka

Keyword(s):

Quantitative Trait ◽

Genome Wide Association Study ◽

Association Studies ◽

Genome Wide Association ◽

Genome Wide Association Studies ◽

Multiple Traits ◽

Leaf Architecture ◽

Genome Wide ◽

Multivariate Gwas ◽

Genomic Regions

Abstract Maize inflorescence is a complex phenotype that involves the physical and developmental interplay of multiple traits. Given the evidence that genes could pleiotropically contribute to several of these traits, we used publicly available maize data to assess the ability of multivariate genome-wide association study (GWAS) approaches to identify pleiotropic quantitative trait loci (pQTL). Our analysis of 23 publicly available inflorescence and leaf-related traits in a diversity panel of n = 281 maize lines genotyped with 376,336 markers revealed that the two multivariate GWAS approaches we tested were capable of identifying pQTL in genomic regions coinciding with similar associations found in previous studies. We then conducted a parallel simulation study on the same individuals, where it was shown that multivariate GWAS approaches yielded a higher true-positive quantitative trait nucleotide (QTN) detection rate than comparable univariate approaches for all evaluated simulation settings except for when the correlated simulated traits had a heritability of 0.9. We therefore conclude that the implementation of state-of-the-art multivariate GWAS approaches is a useful tool for dissecting pleiotropy and their more widespread implementation could facilitate the discovery of genes and other biological mechanisms underlying maize inflorescence.

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Statistical Correction of the Winner’s Curse Explains Replication Variability in Quantitative Trait Genome-Wide Association Studies

10.1101/104786 ◽

2017 ◽

Cited By ~ 3

Author(s):

Cameron Palmer ◽

Itsik Pe’er

Keyword(s):

Quantitative Trait ◽

Quantitative Traits ◽

Association Studies ◽

Genome Wide Association ◽

Genome Wide Association Studies ◽

Cohort Size ◽

Winner's Curse ◽

Winner’S Curse ◽

Genome Wide ◽

Attempted Replication

AbstractGenome-wide association studies (GWAS) have identified hundreds of SNPs responsible for variation in human quantitative traits. However, genome-wide-significant associations often fail to replicate across independent cohorts, in apparent inconsistency with their apparent strong effects in discovery cohorts. This limited success of replication raises pervasive questions about the utility of the GWAS field. We identify all 332 studies of quantitative traits from the NHGRI-EBI GWAS Database with attempted replication. We find that the majority of studies provide insufficient data to evaluate replication rates. The remaining papers replicate significantly worse than expected (p < 10−14), even when adjusting for regression-to-the-mean of effect size between discovery- and replication-cohorts termed the Winner’s Curse (p < 10−16). We show this is due in part to misreporting replication cohort-size as a maximum number, rather than per-locus one. In 39 studies accurately reporting per-locus cohort-size for attempted replication of 707 loci in samples with similar ancestry, replication rate matched expectation (predicted 458, observed 457, p = 0.94). In contrast, ancestry differences between replication and discovery (13 studies, 385 loci) cause the most highly-powered decile of loci to replicate worse than expected, due to difference in linkage disequilibrium.Author SummaryThe majority of associations between common genetic variation and human traits come from genome-wide association studies, which have analyzed millions of single-nucleotide polymorphisms in millions of samples. These kinds of studies pose serious statistical challenges to discovering new associations. Finite resources restrict the number of candidate associations that can brought forward into validation samples, introducing the need for a significance threshold. This threshold creates a phenomenon called the Winner’s Curse, in which candidate associations close to the discovery threshold are more likely to have biased overestimates of the variant’s true association in the sampled population. We survey all human quantitative trait association studies that validated at least one signal. We find the majority of these studies do not publish sufficient information to actually support their claims of replication. For studies that did, we computationally correct the Winner’s Curse and evaluate replication performance. While all variants combined replicate significantly less than expected, we find that the subset of studies that (1) perform both discovery and replication in samples of the same ancestry; and (2) report accurate per-variant sample sizes, replicate as expected. This study provides strong, rigorous evidence for the broad reliability of genome-wide association studies. We furthermore provide a model for more efficient selection of variants as candidates for replication, as selecting variants using cursed discovery data enriches for variants with little real evidence for trait association.

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Genome-wide association studies identify 137 genetic loci for DNA methylation biomarkers of aging

Genome Biology ◽

10.1186/s13059-021-02398-9 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Daniel L. McCartney ◽

Josine L. Min ◽

Rebecca C. Richmond ◽

Ake T. Lu ◽

Maria K. Sobczyk ◽

...

Keyword(s):

Dna Methylation ◽

Genome Wide Association Study ◽

Association Studies ◽

Genome Wide Association ◽

Biological Aging ◽

Genome Wide Association Studies ◽

Genetic Loci ◽

Biomarkers Of Aging ◽

Genome Wide ◽

Shared Genetic

Abstract Background Biological aging estimators derived from DNA methylation data are heritable and correlate with morbidity and mortality. Consequently, identification of genetic and environmental contributors to the variation in these measures in populations has become a major goal in the field. Results Leveraging DNA methylation and SNP data from more than 40,000 individuals, we identify 137 genome-wide significant loci, of which 113 are novel, from genome-wide association study (GWAS) meta-analyses of four epigenetic clocks and epigenetic surrogate markers for granulocyte proportions and plasminogen activator inhibitor 1 levels, respectively. We find evidence for shared genetic loci associated with the Horvath clock and expression of transcripts encoding genes linked to lipid metabolism and immune function. Notably, these loci are independent of those reported to regulate DNA methylation levels at constituent clock CpGs. A polygenic score for GrimAge acceleration showed strong associations with adiposity-related traits, educational attainment, parental longevity, and C-reactive protein levels. Conclusion This study illuminates the genetic architecture underlying epigenetic aging and its shared genetic contributions with lifestyle factors and longevity.

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Metabolome-scale genome-wide association studies reveal chemical diversity and genetic control of maize specialized metabolites

10.1101/450338 ◽

2018 ◽

Author(s):

Zhou Shaoqun ◽

Karl A. Kremling ◽

Bandillo Nonoy ◽

Richter Annett ◽

Ying K. Zhang ◽

...

Keyword(s):

Quantitative Trait ◽

Citrate Synthase ◽

Association Studies ◽

Inbred Lines ◽

Chemical Diversity ◽

Genome Wide Association ◽

Genome Wide Association Studies ◽

Single Linkage ◽

Genome Wide ◽

Maize Varieties

One Sentence SummaryHPLC-MS metabolite profiling of maize seedlings, in combination with genome-wide association studies, identifies numerous quantitative trait loci that influence the accumulation of foliar metabolites.AbstractCultivated maize (Zea mays) retains much of the genetic and metabolic diversity of its wild ancestors. Non-targeted HPLC-MS metabolomics using a diverse panel of 264 maize inbred lines identified a bimodal distribution in the prevalence of foliar metabolites. Although 15% of the detected mass features were present in >90% of the inbred lines, the majority were found in <50% of the samples. Whereas leaf bases and tips were differentiated primarily by flavonoid abundance, maize varieties (stiff-stalk, non-stiff-stalk, tropical, sweet corn, and popcorn) were differentiated predominantly by benzoxazinoid metabolites. Genome-wide association studies (GWAS), performed for 3,991 mass features from the leaf tips and leaf bases, showed that 90% have multiple significantly associated loci scattered across the genome. Several quantitative trait locus hotspots in the maize genome regulate the abundance of multiple, often metabolically related mass features. The utility of maize metabolite GWAS was demonstrated by confirming known benzoxazinoid biosynthesis genes, as well as by mapping isomeric variation in the accumulation of phenylpropanoid hydroxycitric acid esters to a single linkage block in a citrate synthase-like gene. Similar to gene expression databases, this metabolomic GWAS dataset constitutes an important public resource for linking maize metabolites with biosynthetic and regulatory genes.

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Heritability and genome-wide association study of diffusing capacity of the lung

10.1101/277343 ◽

2018 ◽

Author(s):

Natalie Terzikhan ◽

Fangui Sun ◽

Fien M. Verhamme ◽

Hieab H.H. Adams ◽

Daan Loth ◽

...

Keyword(s):

Genome Wide Association Study ◽

Association Studies ◽

Meta Analysis ◽

Genome Wide Association ◽

Considerable Proportion ◽

Genome Wide Association Studies ◽

Diffusing Capacity ◽

Human Lung Tissue ◽

Alveolar Volume ◽

Genome Wide

AbstractBackgroundAlthough several genome wide association studies (GWAS) have investigated the genetics of pulmonary ventilatory function, little is known about the genetic factors that influence gas exchange.AimTo investigate the heritability of, and genetic variants associated with the diffusing capacity of the lung.MethodsGWAS was performed on diffusing capacity, measured by carbon monoxide uptake (DLCO) and per alveolar volume (DLCO/VA) using the single-breath technique, in 8,372 individuals from two population-based cohort studies, the Rotterdam Study and the Framingham Heart Study. Heritability was estimated in related (n=6,246) and unrelated (n=3,286) individuals.ResultsHeritability of DLCO and DLCO/VA ranged between 23% and 28% in unrelated individuals and between 45% and 49% in related individuals. Meta-analysis identified a genetic variant in GPR126 that is significantly associated with DLCO/VA. Gene expression analysis of GPR126 in human lung tissue revealed a decreased expression in patients with COPD and subjects with decreased DLCO/VA.ConclusionDLCO and DLCO/VA are heritable traits, with a considerable proportion of variance explained by genetics. A functional variant in GPR126 gene region was significantly associated with DLCO/VA. Pulmonary GPR126 expression was decreased in patients with COPD.

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Genotypic and Phenotypic Characterization of Lettuce Bacterial Pathogen Xanthomonas hortorum pv. vitians Populations Collected in Quebec, Canada

Agronomy ◽

10.3390/agronomy11122386 ◽

2021 ◽

Vol 11 (12) ◽

pp. 2386

Author(s):

Pierre-Olivier Hébert ◽

Martin Laforest ◽

Dong Xu ◽

Marie Ciotola ◽

Mélanie Cadieux ◽

...

Keyword(s):

Leaf Spot ◽

Genome Wide Association Study ◽

De Novo ◽

Association Studies ◽

Genome Wide Association ◽

Phenotypic Characterization ◽

Genome Wide Association Studies ◽

Bacterial Leaf Spot ◽

Eastern Canada ◽

Genome Wide

Bacterial leaf spot of lettuce, caused by Xanthomonas hortorum pv. vitians, is an economically important disease worldwide. For instance, it caused around 4 million CAD in losses in only a few months during the winter of 1992 in Florida. Because only one pesticide is registered to control this disease in Canada, the development of lettuce cultivars tolerant to bacterial leaf spot remains the most promising approach to reduce the incidence and severity of the disease in lettuce fields. The lack of information about the genetic diversity of the pathogen, however, impairs breeding programs, especially when disease resistance is tested on newly developed lettuce germplasm lines. To evaluate the diversity of X. hortorum pv. vitians, a multilocus sequence analysis was performed on 694 isolates collected in Eastern Canada through the summers of 2014 to 2017 and two isolates in 1996 and 2007. All isolates tested were clustered into five phylogroups. Six pathotypes were identified following pathogenicity tests conducted in greenhouses, but when phylogroups were compared with pathotypes, no correlation could be drawn. However, in vitro production of xanthan and xanthomonadins was investigated, and isolates with higher production of xanthomonadins were generally causing less severe symptoms on the tolerant cultivar Little Gem. Whole-genome sequencing was undertaken for 95 isolates belonging to the pathotypes identified, and de novo assembly made with reads unmapped to the reference strain’s genome sequence resulted in 694 contigs ranging from 128 to 120,795 bp. Variant calling was performed prior to genome-wide association studies computed with single-nucleotide polymorphisms (SNPs), copy-number variants and gaps. Polymorphisms with significant p-values were only found on the cultivar Little Gem. Our results allowed molecular identification of isolates likely to cause bacterial leaf spot of lettuce, using two SNPs identified through genome-wide association study.

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Prioritization of genes associated with the pathogenesis of leukosis in cattle

Vavilov Journal of Genetics and Breeding ◽

10.18699/vj18.451 ◽

2019 ◽

Vol 22 (8) ◽

pp. 1063-1069 ◽

Cited By ~ 1

Author(s):

N. S. Yudin ◽

N. L. Podkolodnyy ◽

T. A. Agarkova ◽

E. V. Ignatieva

Keyword(s):

Protein Interactions ◽

Genome Wide Association Study ◽

Association Studies ◽

Mammalian Species ◽

Genome Wide Association ◽

Farm Animals ◽

Genome Wide Association Studies ◽

Protein Protein Interactions ◽

Genome Wide ◽

A Genome

Selection by means of genetic markers is a promising approach to the eradication of infectious diseases in farm animals, especially in the absence of eﬀective methods of treatment and prevention. Bovine leukemia virus (BLV) is spread throughout the world and represents one of the biggest problems for the livestock production and food security in Russia. However, recent genome-wide association studies have shown that sensitivity/resistance to BLV is polygenic. The aim of this study was to create a catalog of cattle genes and genes of other mammalian species involved in the pathogenesis of BLV-induced infection and to perform gene prioritization using bioinformatics methods. Based on manually collected information from a range of open sources, a total of 446 genes were included in the catalog of cattle genes and genes of other mammals involved in the pathogenesis of BLV-induced infection. The following criteria were used to prioritize 446 genes from the catalog: (1) the gene is associated with leukemia according to a genome-wide association study; (2) the gene is associated with leukemia according to a case-control study; (3) the role of the gene in leukemia development has been studied using knockout mice; (4) protein-protein interactions exist between the gene-encoded protein and either viral particles or individual viral proteins; (5) the gene is annotated with Gene Ontology terms that are overrepresented for a given list of genes; (6) the gene participates in biological pathways from the KEGG or REACTOME databases, which are over-represented for a given list of genes; (7) the protein encoded by the gene has a high number of protein-protein interactions with proteins encoded by other genes from the catalog. Based on each criterion, a rank was assigned to each gene. Then the ranks were summarized and an overall rank was determined. Prioritization of 446 candidate genes allowed us to identify 5 genes of interest (TNF,LTB,BOLA-DQA1,BOLA-DRB3,ATF2), which can aﬀect the sensitivity/resistance of cattle to leukemia.

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Heritability and genome-wide association study of diffusing capacity of the lung

European Respiratory Journal ◽

10.1183/13993003.00647-2018 ◽

2018 ◽

Vol 52 (3) ◽

pp. 1800647 ◽

Cited By ~ 7

Author(s):

Natalie Terzikhan ◽

Fangui Sun ◽

Fien M. Verhamme ◽

Hieab H.H. Adams ◽

Daan Loth ◽

...

Keyword(s):

Genome Wide Association Study ◽

Association Studies ◽

Genome Wide Association ◽

Considerable Proportion ◽

Chronic Obstructive ◽

Genome Wide Association Studies ◽

Diffusing Capacity ◽

Human Lung Tissue ◽

Alveolar Volume ◽

Genome Wide

Although several genome-wide association studies (GWAS) have investigated the genetics of pulmonary ventilatory function, little is known about the genetic factors that influence gas exchange. The aim of the study was to investigate the heritability of, and genetic variants associated with the diffusing capacity of the lung.GWAS was performed on diffusing capacity of the lung measured by carbon monoxide uptake (DLCO) and per alveolar volume (VA) using the single-breath technique, in 8372 individuals from two population-based cohort studies, the Rotterdam Study and the Framingham Heart Study. Heritability was estimated in related (n=6246) and unrelated (n=3286) individuals.Heritability of DLCO and DLCO/VA ranged between 23% and 28% in unrelated individuals and between 45% and 49% in related individuals. Meta-analysis identified a genetic variant in ADGRG6 that is significantly associated with DLCO/VA. Gene expression analysis of ADGRG6 in human lung tissue revealed a decreased expression in patients with chronic obstructive pulmonary disease (COPD) and subjects with decreased DLCO/VA.DLCO and DLCO/VA are heritable traits, with a considerable proportion of variance explained by genetics. A functional variant in ADGRG6 gene region was significantly associated with DLCO/VA. Pulmonary ADGRG6 expression was decreased in patients with COPD.

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