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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/read_vcfs_as_granges.R
\name{read_vcfs_as_granges}
\alias{read_vcfs_as_granges}
\title{Read VCF files into a GRangesList}
\usage{
read_vcfs_as_granges(
vcf_files,
sample_names,
genome,
group = c("auto+sex", "auto", "sex", "circular", "all", "none"),
type = c("snv", "indel", "dbs", "mbs", "all"),
change_seqnames = TRUE,
predefined_dbs_mbs = FALSE,
remove_duplicate_variants = TRUE
)
}
\arguments{
\item{vcf_files}{Character vector of VCF file names}
\item{sample_names}{Character vector of sample names}
\item{genome}{BSgenome reference genome object}
\item{group}{Selector for a seqlevel group. All seqlevels outside
of this group will be removed. Possible values:
* 'all' for all chromosomes;
* 'auto' for autosomal chromosomes;
* 'sex' for sex chromosomes;
* 'auto+sex' for autosomal + sex chromosomes (default);
* 'circular' for circular chromosomes;
* 'none' for no filtering, which results in keeping all
seqlevels from the VCF file.}
\item{type}{The mutation type that will be loaded. All other variants will be filtered out.
Possible values:
* 'snv' (default)
* 'indel'
* 'dbs'
* 'mbs'
* 'all'
When you use 'all', no filtering or merging of variants is performed.}
\item{change_seqnames}{Boolean. Whether to change the seqlevelsStyle of the
vcf to that of the BSgenome object. (default = TRUE)}
\item{predefined_dbs_mbs}{Boolean. Whether DBS and MBS variants have been
predefined in your vcf. This function by default assumes that DBS and MBS
variants are present in the vcf as SNVs, which are positioned next to each
other. If your DBS/MBS variants are called separately you should set this
argument to TRUE. (default = FALSE)}
\item{remove_duplicate_variants}{Boolean. Whether duplicate variants are
removed. This is based on genomic coordinates and does not take the
alternative bases into account. It is generally recommended to keep this
on. Turning this off can result in warnings in plot_rainfall. When a
duplicate SNV is identified as part of a DBS, only a single DBS, instead of
a duplicate DBS will be formed. (default = TRUE)}
}
\value{
A GRangesList containing the GRanges obtained from 'vcf_files'
}
\description{
This function reads Variant Call Format (VCF) files into a GRanges object
and combines them in a GRangesList. In addition to loading the files, this
function applies the same seqlevel style to the GRanges objects as the
reference genome passed in the 'genome' parameter.
By default only reads in snv variants.
}
\examples{
## The example data set consists of three colon samples, three intestine
## samples and three liver samples. So, to map each file to its appropriate
## sample name, we create a vector containing the sample names:
sample_names <- c(
"colon1", "colon2", "colon3",
"intestine1", "intestine2", "intestine3",
"liver1", "liver2", "liver3"
)
## We assemble a list of files we want to load. These files match the
## sample names defined above.
vcf_files <- list.files(system.file("extdata",
package = "MutationalPatterns"
),
pattern = "sample.vcf", full.names = TRUE
)
## Get a reference genome BSgenome object.
ref_genome <- "BSgenome.Hsapiens.UCSC.hg19"
library("BSgenome")
library(ref_genome, character.only = TRUE)
## This function loads the files as GRanges objects.
## For backwards compatability reasons it only loads SNVs by default
vcfs <- read_vcfs_as_granges(vcf_files, sample_names, ref_genome)
## To load all variant types use:
vcfs <- read_vcfs_as_granges(vcf_files, sample_names, ref_genome, type = "all")
## Loading only indels can be done like this.
## Select data containing indels.
vcf_fnames <- list.files(system.file("extdata", package = "MutationalPatterns"),
pattern = "blood.*vcf", full.names = TRUE
)
sample_names <- c("AC", "ACC55", "BCH")
## Read data and select only the indels.
## Other mutation types can be read in the same way.
read_vcfs_as_granges(vcf_fnames, sample_names, ref_genome, type = "indel")
}
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