Genevar is a platform of database and web services designed for integrative analysis and visualization of SNP-gene associations in eQTL (expression quantitative trait loci) studies.
Through interactive Java interface, Genevar allows researchers to investigate eQTL association patterns within a genetic region of interest instantly. The database can be installed on a standard computer in database mode to facilitate unpublished data as well as on a secure server to share discoveries among affiliations or the broader community via web-services protocols.
Default server at the Sanger Institute contains sequence variation and gene expression profiling data from the following datasets:
[Genome Research Limited]
Identify eQTLs centred on the gene of interest across tissues/populations:
Investigate SNP-gene associations surrounding eSNPs/lead SNPs among tissues/populations:
Illustrate SNP-probe associations across cell types/populations:
Genevar and the database are freely available under the terms of the GNU Lesser General Public License.
The easiset way to run Genevar database is to download the noinstall, portable package (with empty template tables):
If an existing MySQL database is installed or not using Windows system:
shell> cd BASEDIR shell> bin/mysqld --standalone
shell> bin/mysql -u root -p mysql> CREATE DATABASE tpy_team16_genevar_2_0_0; mysql> CREATE USER 'tpy'@'localhost' IDENTIFIED BY 'ypt'; mysql> GRANT SELECT, INSERT, UPDATE, CREATE, DROP, ALTER ON tpy_team16_genevar_2_0_0.* TO 'tpy'@'localhost';
shell> bin/mysql -u tpy -p tpy_team16_genevar_2_0_0 < tpy_team16_genevar_2_0_0_20100519.sql
shell> bin/mysqladmin -u root shutdown
Genevar local database mode currently supports the following load data formats.
Illumina HumanRef-8 v3, HumanWG-6 v2, v3 and HumanHT-12 v3 BeadChips:
PROBE_ID SMP001 SMP002 ILMN_0000001 7.26 7.1 ILMN_0000002 12.73 11.58
PLINK formats:
7 rs0001 0 12345 A T 7 rs0002 0 56789 C G
FAM001 SMP001 0 0 0 0 A A G G FAM002 SMP002 0 0 0 0 A T C G
Team16 merged format:
Chr Position SNP_ID Alleles SMP001 SMP002 7 12345 rs0001 A/T AA AT 7 56789 rs0002 C/G GG CG
Genevar and the database are freely available under the terms of the GNU Lesser General Public License.
3.2.0, released on 26 July 2011
[Whats new]
3.1.1
, released on 15 December 2011
[Whats new]
3.1.0, released on 7 December 2011
[Whats new]
[Known issues]
3.0.2, released on 15 July 2011
[Whats new]
3.0.1 (was 3.5.0), released on 14 February 2011
[Known issues]
If you have ever encountered an error message Data not found exception whilst accessing your local database then this might affect you:
Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1HH, UK.
Genevar (GENe Expression VARiation) is a database and Java tool designed to integrate multiple datasets, and provides analysis and visualization of associations between sequence variation and gene expression. Genevar allows researchers to investigate expression quantitative trait loci (eQTL) associations within a gene locus of interest in real time. The database and application can be installed on a standard computer in database mode and, in addition, on a server to share discoveries among affiliations or the broader community over the Internet via web services protocols. AVAILABILITY: http://www.sanger.ac.uk/resources/software/genevar.
Funded by: Wellcome Trust
Bioinformatics (Oxford, England) 2010;26;19;2474-6
PUBMED: 20702402; PMC: 2944204; DOI: 10.1093/bioinformatics/btq452
Wellcome Trust Sanger Institute, Hinxton, UK.
Sequence-based variation in gene expression is a key driver of disease risk. Common variants regulating expression in cis have been mapped in many expression quantitative trait locus (eQTL) studies, typically in single tissues from unrelated individuals. Here, we present a comprehensive analysis of gene expression across multiple tissues conducted in a large set of mono- and dizygotic twins that allows systematic dissection of genetic (cis and trans) and non-genetic effects on gene expression. Using identity-by-descent estimates, we show that at least 40% of the total heritable cis effect on expression cannot be accounted for by common cis variants, a finding that reveals the contribution of low-frequency and rare regulatory variants with respect to both transcriptional regulation and complex trait susceptibility. We show that a substantial proportion of gene expression heritability is trans to the structural gene, and we identify several replicating trans variants that act predominantly in a tissue-restricted manner and may regulate the transcription of many genes.
Funded by: Wellcome Trust: 081917/Z/07/Z, 085235, 090532
Nature genetics 2012;44;10;1084-9
PUBMED: 22941192; DOI: 10.1038/ng.2394
Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, UK.
The genetic basis of gene expression variation has long been studied with the aim to understand the landscape of regulatory variants, but also more recently to assist in the interpretation and elucidation of disease signals. To date, many studies have looked in specific tissues and population-based samples, but there has been limited assessment of the degree of inter-population variability in regulatory variation. We analyzed genome-wide gene expression in lymphoblastoid cell lines from a total of 726 individuals from 8 global populations from the HapMap3 project and correlated gene expression levels with HapMap3 SNPs located in cis to the genes. We describe the influence of ancestry on gene expression levels within and between these diverse human populations and uncover a non-negligible impact on global patterns of gene expression. We further dissect the specific functional pathways differentiated between populations. We also identify 5,691 expression quantitative trait loci (eQTLs) after controlling for both non-genetic factors and population admixture and observe that half of the cis-eQTLs are replicated in one or more of the populations. We highlight patterns of eQTL-sharing between populations, which are partially determined by population genetic relatedness, and discover significant sharing of eQTL effects between Asians, European-admixed, and African subpopulations. Specifically, we observe that both the effect size and the direction of effect for eQTLs are highly conserved across populations. We observe an increasing proximity of eQTLs toward the transcription start site as sharing of eQTLs among populations increases, highlighting that variants close to TSS have stronger effects and therefore are more likely to be detected across a wider panel of populations. Together these results offer a unique picture and resource of the degree of differentiation among human populations in functional regulatory variation and provide an estimate for the transferability of complex trait variants across populations.
Funded by: Wellcome Trust
PLoS genetics 2012;8;4;e1002639
PUBMED: 22532805; PMC: 3330104; DOI: 10.1371/journal.pgen.1002639
Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom.
While there have been studies exploring regulatory variation in one or more tissues, the complexity of tissue-specificity in multiple primary tissues is not yet well understood. We explore in depth the role of cis-regulatory variation in three human tissues: lymphoblastoid cell lines (LCL), skin, and fat. The samples (156 LCL, 160 skin, 166 fat) were derived simultaneously from a subset of well-phenotyped healthy female twins of the MuTHER resource. We discover an abundance of cis-eQTLs in each tissue similar to previous estimates (858 or 4.7% of genes). In addition, we apply factor analysis (FA) to remove effects of latent variables, thus more than doubling the number of our discoveries (1,822 eQTL genes). The unique study design (Matched Co-Twin Analysis--MCTA) permits immediate replication of eQTLs using co-twins (93%-98%) and validation of the considerable gain in eQTL discovery after FA correction. We highlight the challenges of comparing eQTLs between tissues. After verifying previous significance threshold-based estimates of tissue-specificity, we show their limitations given their dependency on statistical power. We propose that continuous estimates of the proportion of tissue-shared signals and direct comparison of the magnitude of effect on the fold change in expression are essential properties that jointly provide a biologically realistic view of tissue-specificity. Under this framework we demonstrate that 30% of eQTLs are shared among the three tissues studied, while another 29% appear exclusively tissue-specific. However, even among the shared eQTLs, a substantial proportion (10%-20%) have significant differences in the magnitude of fold change between genotypic classes across tissues. Our results underline the need to account for the complexity of eQTL tissue-specificity in an effort to assess consequences of such variants for complex traits.
Funded by: Wellcome Trust: 077016/Z/05/Z, 085235
PLoS genetics 2011;7;2;e1002003
PUBMED: 21304890; PMC: 3033383; DOI: 10.1371/journal.pgen.1002003
Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, CB10 1HH, Cambridge, UK.
Studies correlating genetic variation to gene expression facilitate the interpretation of common human phenotypes and disease. As functional variants may be operating in a tissue-dependent manner, we performed gene expression profiling and association with genetic variants (single-nucleotide polymorphisms) on three cell types of 75 individuals. We detected cell type-specific genetic effects, with 69 to 80% of regulatory variants operating in a cell type-specific manner, and identified multiple expressive quantitative trait loci (eQTLs) per gene, unique or shared among cell types and positively correlated with the number of transcripts per gene. Cell type-specific eQTLs were found at larger distances from genes and at lower effect size, similar to known enhancers. These data suggest that the complete regulatory variant repertoire can only be uncovered in the context of cell-type specificity.
Funded by: Wellcome Trust: 077011, 077046
Science (New York, N.Y.) 2009;325;5945;1246-50
PUBMED: 19644074; PMC: 2867218; DOI: 10.1126/science.1174148