wgcna: An implementation of WGCNA to correlate coexpression modules...

Description Usage Arguments Details Value Author(s) References

View source: R/wcgna.R

Description

An implementation of WGCNA to correlate coexpression modules to disease

Usage

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wgcna(MODifieR_input, group_of_interest, minModuleSize = 30,
  deepSplit = 2, pamRespectsDendro = F, mergeCutHeight = 0.1,
  numericLabels = T, pval_cutoff = 0.05, corType = "bicor",
  maxBlockSize = 5000, TOMType = "signed", saveTOMs = T,
  maxPOutliers = 0.1,
  dataset_name = deparse(substitute(MODifieR_input)))

Arguments

MODifieR_input

A MODifieR input object produced by one of the create_input functions

group_of_interest

Numerical value denoting which group contains the condition of interest (1 or 2)

minModuleSize

minimum module size for module detection. See cutreeDynamic for more details.

deepSplit

integer value between 0 and 4. Provides a simplified control over how sensitive module detection should be to module splitting, with 0 least and 4 most sensitive. See cutreeDynamic for more details.

pamRespectsDendro

Logical, only used when pamStage is TRUE. If TRUE, the PAM stage will respect the dendrogram in the sense an object can be PAM-assigned only to clusters that lie below it on the branch that the object is merged into. See cutreeDynamic for more details.

mergeCutHeight

dendrogram cut height for module merging.

numericLabels

logical: should the returned modules be labeled by colors (FALSE), or by numbers (TRUE)?

pval_cutoff

The p-value cutoff to be used for significant co-expression modules (colors)

corType

character string specifying the correlation to be used. Allowed values are (unique abbreviations of) "pearson" and "bicor", corresponding to Pearson and bidweight midcorrelation, respectively. Missing values are handled using the pairwise.complete.obs option.

maxBlockSize

integer giving maximum block size for module detection. Ignored if blocks above is non-NULL. Otherwise, if the number of genes in datExpr exceeds maxBlockSize, genes will be pre-clustered into blocks whose size should not exceed maxBlockSize.

TOMType

one of "none", "unsigned", "signed". If "none", adjacency will be used for clustering. If "unsigned", the standard TOM will be used (more generally, TOM function will receive the adjacency as input). If "signed", TOM will keep track of the sign of correlations between neighbors.

saveTOMs

logical: should the consensus topological overlap matrices for each block be saved and returned?

maxPOutliers

only used for corType=="bicor". Specifies the maximum percentile of data that can be considered outliers on either side of the median separately. For each side of the median, if higher percentile than maxPOutliers is considered an outlier by the weight function based on 9*mad(x), the width of the weight function is increased such that the percentile of outliers on that side of the median equals maxPOutliers. Using maxPOutliers=1 will effectively disable all weight function broadening; using maxPOutliers=0 will give results that are quite similar (but not equal to) Pearson correlation.

dataset_name

Optional name for the input object that will be stored in the settings object. Default is the variable name of the input object

Details

wgcna is an implementation of WGCNA that associates co-expression modules (denoted by color) to a trait. Co-expression modules with an adjusted p-value < pval_cutoff will make up the final disease module.

The algorithm infers co-expression modules from combined expression dataset from both group1 and group2. Co-expression modules are then correlated to trait (group 1 ~ group 2).

After analysis there are some post-processing functions available:

Value

wgcna returns an object of class "MODifieR_module" with subclass "WGCNA". This object is a named list containing the following components:

module_genes

A character vector containing the genes in the final module

info_table

A data.frame containing all genes and their assigned colors

correlation_to_trait_table

A data.frame containing all module colors and their p- and adjusted p-value

softthreshold_value

A numeric, the soft threshold power that is used. See: pickSoftThreshold

module_colors

A character vector containing the colors that make up the final disease module

settings

A named list containing the parameters used in generating the object

Author(s)

Dirk de Weerd

References

Langfelder P and Horvath S, WGCNA: an R package for weighted correlation network analysis. BMC Bioinformatics 2008, 9:559 doi:10.1186/1471-2105-9-559

Peter Langfelder, Steve Horvath (2012). Fast R Functions for Robust Correlations and Hierarchical Clustering. J ournal of Statistical Software, 46(11), 1-17. URL http://www.jstatsoft.org/v46/i11/


ddeweerd/MODifieRDev documentation built on Nov. 12, 2019, 7:50 a.m.