plot_volcano: Volcano plot for log fold changes and log p-values

In ideal: Interactive Differential Expression AnaLysis

Description

Volcano plot for log fold changes and log p-values in the ggplot2 framework, with additional support to annotate genes if provided.

Usage

plot_volcano(
  res_obj,
  FDR = 0.05,
  ylim_up = NULL,
  vlines = NULL,
  title = NULL,
  intgenes = NULL,
  intgenes_color = "steelblue",
  labels_intgenes = TRUE
)

Arguments

res_obj	A DESeqResults object
FDR	Numeric value, the significance level for thresholding adjusted p-values
ylim_up	Numeric value, Y axis upper limits to restrict the view
vlines	The x coordinate (in absolute value) where to draw vertical lines, optional
title	A title for the plot, optional
intgenes	Vector of genes of interest. Gene symbols if a symbol column is provided in res_obj, or else the identifiers specified in the row names
intgenes_color	The color to use to mark the genes on the main plot.
labels_intgenes	Logical, whether to add the gene identifiers/names close to the marked plots

Details

The genes of interest are to be provided as gene symbols if a symbol column is provided in res_obj, or else b< using the identifiers specified in the row names

Value

An object created by ggplot

Examples

library(airway)
data(airway)
airway
dds_airway <- DESeq2::DESeqDataSetFromMatrix(assay(airway),
                                             colData = colData(airway),
                                             design=~cell+dex)
                                             
# subsetting for quicker run, ignore the next two commands if regularly using the function 
gene_subset <- c(
  "ENSG00000103196",  # CRISPLD2
  "ENSG00000120129",  # DUSP1
  "ENSG00000163884",  # KLF15
  "ENSG00000179094",  # PER1
  rownames(dds_airway)[rep(c(rep(FALSE,99), TRUE), length.out=nrow(dds_airway))]) # 1% of ids
dds_airway <- dds_airway[gene_subset,]

dds_airway <- DESeq2::DESeq(dds_airway)
res_airway <- DESeq2::results(dds_airway)

plot_volcano(res_airway)

ideal documentation built on Nov. 8, 2020, 5:02 p.m.