Package 'consensusDE'

Title: RNA-seq analysis using multiple algorithms
Description: This package allows users to perform DE analysis using multiple algorithms. It seeks consensus from multiple methods. Currently it supports "Voom", "EdgeR" and "DESeq". It uses RUV-seq (optional) to remove unwanted sources of variation.
Authors: Ashley J. Waardenberg [aut, cre], Martha M. Cooper [ctb]
Maintainer: Ashley J. Waardenberg <[email protected]>
License: GPL-3
Version: 1.25.0
Built: 2024-10-30 05:36:16 UTC
Source: https://github.com/bioc/consensusDE

Help Index


Generate summarized Read File for DE analyses

Description

This function will create a summarized experiment, decribing reads from RNA-seq experiments that overlap a set of transcript features. Transcript features can be described as a gtf formatted table that is imported, or using a txdb. The summarized experiment can be build directly from bam files or by reading in counts in htseq format. This is designed to be straightforward and with minimised parameters for batch style RNA-seq analyses.

Usage

buildSummarized(sample_table = NULL, bam_dir = NULL,
  htseq_dir = NULL, gtf = NULL, tx_db = NULL,
  technical_reps = FALSE, map_reads = "transcript",
  mapping_mode = "Union", read_format = NULL, strand_mode = 0,
  fragments = FALSE, summarized = NULL, output_log = NULL,
  filter = FALSE, BamFileList_yieldsize = NA_integer_, n_cores = 1,
  force_build = FALSE, verbose = FALSE)

Arguments

sample_table

A data.frame describing samples. For paired mode it must at least 2 columns, "file", "group", and option additional columns, "pairs" and "tech_replicate" for describing sample pairing and instances of technical replicates. The filename "file" must correspong to the name of the file in the directory supplied with the "bam_dir" parameter below - or ar error will be reported and buildSummarized will halt. This is not required if an existing summarized file is provided. Default = NULL

bam_dir

Full path to location of bam files listed in the "file" column in the sample_table provided above. This is not required if an existing summarized file is provided. Default = NULL

htseq_dir

Full path to location of htseq files listed in the "file" column in the sample_table described above. This is not required if an existing summarized file is provided. Files must end in ".txt". Default = NULL

gtf

Full path to a gtf file describing the transcript coordinates to map the RNA-seq reads to. GTF file is not required if providing a pre-computed summarized experiment file previously generated using buildSummarized() OR a tx_db object (below). Default = NULL

tx_db

An R txdb object. E.g. TxDb.Dmelanogaster.UCSC.dm3.ensGene. Default = NULL

technical_reps

Are there technical replicates to merge counts? I.e. are there multiple technical replicates run accross multiple lanes/sequencing runs. If "TRUE", unique sample names should be provided in a "tech_replicate" column of the "sample_table" for identification. Options are "TRUE" or "FALSE". Default = "FALSE"

map_reads

Which features to count reads by. Options are "transcript", "exon" or "cds". This will invoke transcriptsBy(), exonsBy() or cdsBy() respectively. Default = "transcript"

mapping_mode

Options are "Union", "IntersectionStrict" and "IntersectionNotEmpty". see "mode" in ?summarizeOverlaps for explanation. Default = "Union"

read_format

Are the reads from single-end or paired-end data? Option are "paired" or "single". An option must be selected if htseq_dir is NULL and read are summarized from BAM files. Default = NULL

strand_mode

indicates how the reads are stranded. Options are 0 (unstranded); 1 (stranded) and 2 (reverse strandedness). see ?strandMode in Genomic Alignments for explanation. Default = 0

fragments

When mapping_mode = "paired", include reads from pairs that do not map with their corresponding pair? see "fragments" in ?summarizeOverlaps for explanation. Default = TRUE

summarized

Full path to a summarized experiment file. If buildSummarized() has already been performed, the output summarized file, saved in "/output_log/se.R" can be used as the input (e.g. if filtering is to be done). Default = NULL

output_log

Full path to directory for output of log files and saved summarized experiment generated.

filter

Perform filtering of low count and missing data from the summarized experiment file? This uses default filtering via "filterByExpr". See ?filterByExpr for further information. Default = FALSE

BamFileList_yieldsize

If running into memory problems. Set the number of lines to an integer value. See "yieldSize" description in ?BamFileList for an explanation.

n_cores

Number of cores to utilise for reading in Bam files. Use with caution as can create memory issues if BamFileList_yieldsize is not parameterised. Default = 1

force_build

If the sample_table contains less than two replicates per group, force a summarizedExperiment object to be built. Otherwise buildSummarized will halt. Default = FALSE.

verbose

Verbosity ON/OFF. Default = FALSE

Value

A summarized experiment

Examples

## Extract summarized following example in the vignette
## The example below will return a summarized experiment
## tx_db is obtained from TxDb.Dmelanogaster.UCSC.dm3.ensGene library
library(TxDb.Dmelanogaster.UCSC.dm3.ensGene)
## bam files are obtained from the GenomicAlignments package

## 1. Build a sample table that lists files and groupings
## - obtain list of files
file_list <- list.files(system.file("extdata", package="GenomicAlignments"),
                        recursive = TRUE,
                        pattern = "*bam$",
                        full = TRUE)
bam_dir <- as.character(gsub(basename(file_list)[1], "", file_list[1]))

## - create a sample table to be used with buildSummarized() below
## must be comprised of a minimum of two columns, named "file" and "group",
sample_table <- data.frame("file" = basename(file_list),
                           "group" = c("treat", "untreat"))

summarized_dm3 <- buildSummarized(sample_table = sample_table,
                                  bam_dir = bam_dir,
                                  tx_db = TxDb.Dmelanogaster.UCSC.dm3.ensGene,
                                  read_format = "paired",
                                  force_build = TRUE)

QC/diagnostic plotting

Description

Wrappers for a series of plots to be used as diagnostics in RNA-seq analyses. Currently 10 plots are possible using this function: 1) Mapped reads, 2) Relative Log Expression (RLE), 3) Principle Component Analyis (PCA), 4) Residuals from a batch correction model, e.g. RUVseq, 5) Hierarchical clustering, 6) Densitiy distributions, 7) Boxplots, 8) MA plots, 9) Volcano Plots and 10) P-value distribution plots. Plots 1 to 6 utilise a "SeqExpressionSet" object for extracting information to plot. Plots 8-10 utilised a simple list class, containing all the data.frames of each comparison performed. See descriptions of each in the parameter options below and for format specification. See vignette for more information and examples.

Usage

diag_plots(se_in = NULL, merged_in = NULL, write = FALSE,
  plot_dir = NULL, legend = TRUE, label = TRUE, name = NULL,
  mapped_reads = FALSE, rle = FALSE, pca = FALSE,
  residuals = FALSE, hclust = FALSE, density = FALSE,
  boxplot = FALSE, ma = FALSE, volcano = FALSE, p_dist = FALSE)

Arguments

se_in

A "SeqExpressionSet" object or "RangedSummarizedExperiment" generated using "buildSummarized()". If the input is a "SeqExpressionSet", ensure that it included groups to be analysed. E.g. accessible as "se_in$group. Groupings are used to automate colouring of samples in unsupervised analyses. Default = NULL

merged_in

A data.frame that contains the merged results which are included in the outputs from multi_de_pairs(). These contain the ouputs from the pair-wise comparisons which allows plotting of MA, Volcano and p-value distributions. Where the outputs of multi_de_pairs() are to be used as inputs into diag_plots(), use multi_de_pairs()$merged as inputs. See example below. Default = NULL

write

Write the results to a pdf file? Options: TRUE, FALSE. This is to be used together with "plot_dir" and "write" parameters (below). Will report an error and halt if is TRUE and "plot_dir" and "write" are NULL. Default = FALSE

plot_dir

If "write" is TRUE, where to write the files to? The directory must already exist. E.g. "/path/to/my/pretty/plots/". Default = NULL

legend

Include legend in plots? Legend is based on group data in se_in. Options: TRUE, FALSE. Default = FALSE

label

Include point labels in plots? Points are based on ID column from merged_in. Options: TRUE, FALSE. Default = FALSE

name

If "write" is TRUE, what to name the plot? The file name will always be preceded with "QC_" and end in ".pdf". E.g. name="very_pretty_plots" will produce a file named "QC_very_pretty_plots.pdf" in "/path/to/my/pretty/plots/". Default = NULL

mapped_reads

Plot mapped reads per sample as a barchart. Requires se_in to be a "SeqExpressionSet" and utilise "group" meta-data for colouring. Options: TRUE, FALSE. Default = FALSE

rle

Plot Relative Log Expressio (RLE) of samples for assessment of sample quality. See ?plotRLE for further details. Requires se_in to be a "SeqExpressionSet"and utilise "group" meta-data for colouring. Options: TRUE, FALSE. Default = FALSE

pca

Perform unsupervised Principle Component Analysis (PCA) and plot results. By default performs Singular Value Decomposition. Requires se_in to be a "SeqExpressionSet" and utilise "group" meta-data for colouring. Options: TRUE, FALSE. Default = FALSE

residuals

If RUV-seq has been applied to dataset, plot the residuals identified in the model. Only works for one set of residuals. Data is also accessible using pData(se_in)$W_1. Requires se_in to be a "SeqExpressionSet" and utilise "group" meta-data for colouring. Options: TRUE, FALSE. Default = FALSE

hclust

Performs unsupervised hierarchical clustering of samples. Colours sample below plot according to group and numbered by inputs. Requires se_in to be a "SeqExpressionSet" and utilise "group" meta-data for colouring. Options: TRUE, FALSE. Default = FALSE

density

Plot density distributions of log2(count-per-million). Will automatically extract normalised counts over non-normalised counts is available in "SeqExpressionSet". Requires se_in to be a "SeqExpressionSet" and utilise "group" meta-data for colouring. Options: TRUE, FALSE. Default = FALSE

boxplot

Boxplot of density distributions of log2(count-per-million). Will automatically extract normalised counts over non-normalised counts is available in "SeqExpressionSet". Requires se_in to be a "SeqExpressionSet" and utilise "group" meta-data for colouring. Options: TRUE, FALSE. Default = FALSE

ma

Plot Mean versus. Log2 Fold-Change of comparison. Requires a data.frame as input to "merged_in" with the following column names "ID", "AvExpr", "Log2FC" and "Adj_PVal".The data frame should be sorted, as the top 10 in the table are also plotted. Options: TRUE, FALSE. Default = FALSE

volcano

Volcano plot of Log2 Fold-Change and significance of comparison. Requires a data.frame as input to "merged_in" with the following column names "ID", "AvExpr", "Log2FC" and "Adj_PVal". The data frame should be sorted, as the top 10 in the table are also plotted. Options: TRUE, FALSE. Default = FALSE

p_dist

P-value distribution plot. Requires a data.frame as input to "merged_in" with the following column names "ID", "AvExpr", "Log2FC" and "Adj_PVal". The data frame should be sorted, as the top 10 in the table are also plotted. Options: TRUE, FALSE. Default = FALSE

Value

Returns pretty plots

Examples

## Load the example data set and attach
## The example below will display a PCA plot before normalisation
library(airway)
data(airway)
## Name the groups of the data.
colData(airway)$group <- colData(airway)$dex
## Identify the file locations
colData(airway)$file <- rownames(colData(airway))
## Filter low count data:
airway_filter <- buildSummarized(summarized = airway,
                                 filter = TRUE)
## for illustration, use random sample of 1000 transcripts
set.seed(1234)
airway_filter <- sample(airway_filter, 1000)
## The following is example code to perform a PCA plot
## see vignette for more details of displaying each plot
## diag_plots(se_in = airway_filter,
##            name = "airway example data",
##            pca = TRUE)

Batch - multiDE analysis of many comparisons

Description

Given a summarized experiment generated using buildSummarized() this function will automatically perform differential expression (DE) analysis for all possible groups using 3 different methods 1) EdgeR, 2) Voom and 3) DEseq2. It will also output 10x diagnostic plots automatically, if the plotting options are selected (see ?diag_plots for more details).

Usage

multi_de_pairs(summarized = NULL, paired = "unpaired",
  intercept = NULL, adjust_method = "BH", EDASeq_method = "upper",
  norm_method = "EDASeq", ruv_correct = FALSE,
  ensembl_annotate = NULL, gtf_annotate = NULL, plot_dir = NULL,
  output_voom = NULL, output_edger = NULL, output_deseq = NULL,
  output_combined = NULL, verbose = FALSE, legend = TRUE,
  label = TRUE)

Arguments

summarized

A "RangedSummarizedExperiment" object with included groups to be analysed. For format specifications see ?buildSummarized. E.g. accessible as "summarized$group". Groups are used to automate colouring of samples in unsupervised analyses. Default = NULL

paired

Are the sample paired? If "paired" a paired statistical analysis by including factors as pairs described in the "pairs" column of the "RangedSummarizedExperiment" object in the model (accessible as summarized$pairs). Options are "unpaired" or "paired". Default="unpaired"

intercept

Optional ability to set the base term for fitting the model. This is not necessary as all pairs are computed automatically. The base term, if set, must match the name of s group in "summarized$group". Default = NULL

adjust_method

Method used for multiple comparison adjustment of p-values. Options are: "holm", "hochberg", "hommel", "bonferroni", "BH", "BY", "fdr" or "none". See ?p.adjust.methods for a details description and references. Default = "BH"

EDASeq_method

Method for normalisation (applies to QC results using EDASeq and RUV when EDASeq is selected). Options are:"median","upper","full". Default = "upper"

norm_method

Methods for normalisation. Options are: "EDASeq" or "all_defaults". When "all_defaults" is selected, this will use all default normalisation methods for differential expression, EDASeq for QC, and edgeR "upperquantile" for determining RUV residuals (as per RUVSeq vignette). When "EDASeq" is selected, this will use EDASeq normalisation throughout. EDASeq normalisation method is selected using "EDASeq_method". Default = "EDASeq".

ruv_correct

Remove Unwanted Variation (RUV)? See ?RUVr for description. Currently only RUVr, which used the residuals is enabled and one factor of variation is determined. If set to TRUE and a "plot_dir" is provided, additional plots after RUV correction and the RUV residuals will be reported. Residuals are obtained through fitting a generalised linear model (GLM) using EdgeR. Residuals are then incorporated into the SummarizedExperiment object and all models for DE analysis. Options = TRUE, FALSE. Default = FALSE.

ensembl_annotate

If the dataset has been mapped to ensembl transcript identifiers, obtain additional annotation of the ensembl transcripts. A R Genome Wide Annotation object e.g. org.Mm.eg.db for mouse or org.Hs.eg.db for human must be provided. Default = NULL

gtf_annotate

Full path to a gtf file describing the transcripts. If provided will obtain gene symbols from gtf file. If a ensembl_annotate object is also provided, this will extract annotations based on the symbols extracted from the GTF file. It is recommended to provide both a gtf file and a tx_db for better annotation results. Default = NULL

plot_dir

Full path to directory for output of plots (pdf files). See ?diag_plots for more details. Default = NULL

output_voom

If you wish to output the results of the Voom analysis, provide a full path to directory for output of files. Default = NULL

output_edger

If you wish to output the results of the EdgeR analysis, provide a full path to directory for output of files. Default = NULL

output_deseq

If you wish to output the results of the DEseq2 analysis, provide a full path to directory for output of files. Default = NULL

output_combined

consensusDE will report the results of Voom, EdgeR and DEseq2 as a combined report. If you wish to output the results of the COMBINED analysis, provide a full path to directory for output of files. In addition to the combined data, it will also output the raw count and normalised data to the same directory. Default = NULL

verbose

Verbosity ON/OFF. Default=FALSE

legend

Include legend in plots? Legend is based on group data in summarized Options: TRUE, FALSE. Default = TRUE

label

Include point labels in plots? Points are based on ID column after DE analysis from merged results. Options: TRUE, FALSE. Default = TRUE

Value

A list of all the comparisons conducted. ## See vignette for more details.

Examples

## Load the example data set and attach - see vignette for more details
## The example below will perfrom DE analysis on all pairs of data
library(airway)
data(airway)
## Name groups of the data.
colData(airway)$group <- colData(airway)$dex
## Identify file locations
colData(airway)$file <- rownames(colData(airway))
#' ## Filter low count data:
airway_filter <- buildSummarized(summarized = airway,
                                 filter = TRUE)
## for illustration, we only use random sample of 1000 transcripts
set.seed(1234)
airway_filter <- sample(airway_filter, 1000)
## Run multi_de_pairs() with-out RUV correction
## To run with RUV correction, use ruv_correct = TRUE
all_pairs_airway <- multi_de_pairs(summarized = airway_filter,
                                   ruv_correct = FALSE,
                                   paired = "unpaired")