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xQTLbiolinks: a comprehensive and scalable tool for integrative analysis of molecular QTLs

xQTLbiolinks is a end-to-end bioinformatic tool for efficient mining and analyzing public and user-customized xQTLs data for the discovery of disease susceptibility genes. xQTLbiolinks consists of tailored functions that can be grouped into four modules: Data retrieval, Pre-processing, Analysis and Visualization.

Instructions, documentation, and tutorials can be found at here.

Quick Start

  1. xQTLbiolinks can be installed and used on any operator systems supporting R. Once the R (version 4.0 or later) is available, using install.packages("xQTLbiolinks") to install the steady version (v1.6.2) of xQTLbiolinks. The latest version (v1.6.3) is also available at GitHub repository and it can be installed through devtools::install_github("dingruofan/xQTLbiolinks”). For more details, please refer to the instructions at Installation section below.
  2. Find the Query and download for xQTLs, gene, variant, tissue, sample and expressions.
  3. Find the Quick Start for a quick application of colocalization analysis with xQTLbiolinks. Go through a whole Case study of detection of casual vairants and genes in prostate cancer using xQTLbiolinks.
  4. The details and instructions of all functions implemented in xQTLbiolinks can be found here. Find more instructions with examples for visualizations here.

Citation

If you find the xQTLbiolinks package or any of the source code in this repository useful for your work, please cite:

Ruofan Ding, Xudong Zou, Yangmei Qin, Hui Chen, Xuelian Ma, Gao Wang, Lei Li. xQTLbiolinks: a comprehensive and scalable tool for integrative analysis of molecular QTLs. (submitted)

Institute of Systems and Physical Biology, Shenzhen Bay Laboratory, Shenzhen 518055, China


Dependencies

The xQTLbiolinks package has the following dependencies:

R packages: BiocGenerics, cowplot (>= 1.1.1), curl (>= 4.3.2), data.table (>= 1.14.2), DBI, SummarizedExperiment, GenomeInfoDb, GenomicFeatures, GenomicRanges, ggplot2 (>= 3.3.6), ggrepel, IRanges, jsonlite (>= 1.7.2), viridis, RMySQL, stringr (>= 1.4.0), utils (>= 4.0.3),VariantAnnotation, TxDb.Hsapiens.UCSC.hg38.knownGene, PupillometryR, coloc, hyprcoloc, knitr, rtracklayer, usethis, ggridges, CMplot, R.utils, ggforestplot.

Installation

To install this R package, you will need to have required package SummarizedExperiment installed from Bioconductor with following command:

if (!require("BiocManager", quietly = TRUE)){install.packages("BiocManager")}
BiocManager::install("SummarizedExperiment") # For windows or linux
BiocManager::install("SummarizedExperiment",type="source") # For MAC

Once you have installed the required package, you can then install xQTLbiolinks from CRAN or github(recommended) using following command:

# Install from github to get the latest version.
if(!require("remotes")){install.packages("remotes")}
remotes::install_github("dingruofan/xQTLbiolinks")

# This command should automatically install any missing dependencies that are available from CRAN
install.packages("xQTLbiolinks")

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Install

install.packages('xQTLbiolinks')

Monthly Downloads

8

Version

1.6.2

License

GPL (>= 3)

Issues

Pull Requests

Stars

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Maintainer

Ruofan Ding

Last Published

September 14th, 2023

Functions in xQTLbiolinks (1.6.2)

fetchContentEbi

Fetch variant from Ebi
xQTLanno_chippeak

enrichment analysis for GWAS / QTL signals in functional elements, including enhancer, promoter, CPG, and TFs
xQTLanno_genomic

annotate all signals in GWAS / QTL dataset by genome location
xQTLanalyze_getTraits

Identify trait genes using sentinel SNPs generated from xQTLanalyze_getSentinelSnp
fetchContent

Fetch data using url by three methods
xQTLdownload_eqtlExp

Download normalized expression for gene with a variant-gene pair
retrieveLD_LDproxy

Retrieve SNP pairwise LD from LDlink database
xQTLanalyze_coloc_diy

Conduct colocalization analysis with customized QTL data
xQTLdownload_eqtlAllAssoPos

Download summary statistics data for eQTLs with genome positions.
sampleNum

samples used in GTEx eQTL analysis.
xQTLanalyze_getSentinelSnp

Detect sentinel SNPs for GWAS using summary statistics data
xQTLdownload_hqtl

Download summary statistics data of H3K4me1 and H3K27ac histone QTL (hQTL) using a specified location
xQTLdownload_hqtlmeta

Download metadata for H3K4me1 and H3K27ac histone QTL (hQTL)
xQTLanno_calLambda

calculate genomic control inflation factor for a QTL/GWAS summary statistics dataset.
xQTL_export

Export expression object to a specified format
xQTLdownload_geneMedExp

Download median expressions for multiple genes in a specified tissue
xQTLdownload_exp

Download normalized gene expression at the sample level for a specified tissue.
tissueSiteDetailGTExv7

Tissue name and tissue id mapping of GTEx V7.
is.wholenumber

determine whether is a whole number:
retrieveLD

Retrieve SNP pairwise LD from locuscompare database
xQTLdownload_sgene

Download details of sGenes (sQTL Genes) for a specified gene or a tissue.
xQTLdownload_sqtlAllAsso

Download summary statistics data for sQTLs with a specified gene or a tissue
tissueSiteDetailGTExv8

Tissue name and tissue id mapping of GTEx V8.
xQTLquery_gene

Query basic information for genes, including name, symbol, position and description
xQTLdownload_mqtlmeta

Download metadata of DNA methylation QTL (mQTL)
xQTLdownload_mQTL

Download summary statistics data of DNA methylation QTL (mQTL) using CpG ID
xQTLquery_geneAll

Query all genes supported in GTEx
xQTLanalyze_coloc

Conduct colocalization analysis with trait genes generated from xQTLanalyze_getTraits
xQTLquery_varId

Query variant with variant ID or dbSNP ID
xQTLvisual_anno

Visualize enrichment of variants derived from xQTLanno_genomic
xQTLquery_eqtl

Query multi-tissue eQTL metasoft results
xQTLquery_eqtlSig

Query significant eQTL associations for a specified tissue or multiple tissues.
xQTLdownload_xqtlAllAsso

Download summary statistics of xQTL for a specified gene, default:3'aQTL
xQTLvisual_PZPlot

Compare P-values reported to P-values calculated from Z statistics derived from the reported beta and standard error.
xQTLdownload_sqtlExp

Download normalized PSI value of intron for a sQTL pair
xQTLquery_scInfo

Query metadata of sc-eQTLs
xQTLvisual_geneExpTissues

Violin plot of distribution of the gene expression profiles among multiple tissues.
xQTLquery_sc

Query significant sc-eQTLs for a specified gene
xQTLvisual_manhattan

Manhattan plot for a GWAS summary statistics dataset
xQTLvisual_eqtlExp

Boxplot of normalized expression stratified by genotypes for eQTL.
xQTLvisual_sqtl

Box plot with jittered points for showing number and significance of sQTL associations
xQTLdownload_egene

Download eGenes (eQTL Genes) for a specified gene or a tissue
xQTLvisual_qqPlot

Quantile-quantile plot with p-values from GWAS summary statistics data
xQTLquery_sampleBySampleId

Query details of samples with GTEx IDs
xQTLvisual_eqtl

Box plot with jittered points for showing number and significance of eQTL associations
xQTLquery_sampleByTissue

Query details of samples by tissue name
xQTLvisual_coloc

Heatmap plot of the LD-p-value relationship of the eQTL
xQTLdownload_eqtlAllAsso

Download summary statistics data for eQTLs with a specified gene, variant, tissue or study
xQTLdownload_sc

Download all sc-eQTL associations for a specified gene
xQTLquery_tissue

Query details for a specified tissue
xQTLquery_sqtlSig

Query significant sQTL associations for a tissue or multple tissues
xQTLvisual_locusCombine

Generate a combined figure including locusZoom and locuscompare plot
xQTLquery_varPos

Query variants using genome position.
xQTLvisual_genoBox

Boxplot of values stratified by genotypes with customized data
xQTLvisual_sqtlExp

Boxplot of normalized PSI stratified by genotypes for sQTL.
xQTLvisual_locusZoom

Locuszoom plot for visualizing regional signals relative to genomic position with summary statistics data
xQTLvisual_locusCompare

Dotplot of comparing regional signals between GWAS and xQTL
xQTLdownload_scSig

Download significant sc-eQTL associations for a specified gene
dbsnpQueryRange

retrieve snps from dbSNP using coordinate.
EBIquery_allTerm

Query supported terms (phenotypes, studies, tissues) in eQTL catalogue
extractGeneInfo

Extract gene details from gencodeGeneInfoAllGranges object
example_Coloc_colocResultsig

data for vignette
example_Coloc_gwasDF

data for vignette
example_Coloc_traitsAll

data for vignette
example_Coloc_sentinelSNP

data for vignette
gencodeGenetype

Gene types in GTEx V8 and V7
apiEbi_ping

Heartbeat to check EBI API server connectivity.
gencodeGeneInfoAllGranges

Gene annotations (chr1-chr22).
example_Coloc_colocResultAll

data for vignette
apiAdmin_ping

Heartbeat to check GTEx API server connectivity.
ebi_study_tissues

data for vignette
example_Coloc_hyprcolocResultAll

data for vignette