Estimated methylation call

Description

Estimated methylation call based on the fitting results of gammaFitEM

Usage

methylationCall(x, threshold = 0.95, ...)

Arguments

Details

Retrieve the probability element returned by gammaFitEM, and convert it as three status calls based on probability threshold

NOTE: the methylation status modeling algorithm was developed based on 27K methylation array. It has not been tested for 450K array. Considering 450K array covers both promoter and gene body, the two component Gamma mixture model assumption may not be valid any more.

Value

A vector of three methylation status: "Unmethy" (unmethylation posterior probability > unmethylation threshold), "Methy" (methylation posterior probability > methylation threshold), or "Margin". The sum of unmethylation posterior probability and methylation posterior probability equals one. The methylation probability is returned as an attribute of "probability".

Author(s)

Pan DU

See Also

gammaFitEM

Examples

data(example.lumiMethy)
M <- exprs(example.lumiMethy)
fittedGamma <- gammaFitEM(M[,1], initialFit=NULL, maxIteration=50, tol=0.0001, plotMode=TRUE, verbose=FALSE)
methyCall <- methylationCall(fittedGamma)
table(methyCall)

Results

R version 3.3.1 (2016-06-21) -- "Bug in Your Hair"
Copyright (C) 2016 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

R is free software and comes with ABSOLUTELY NO WARRANTY.
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Type 'license()' or 'licence()' for distribution details.

R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.

Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.

> library(lumi)
Loading required package: Biobase
Loading required package: BiocGenerics
Loading required package: parallel

Attaching package: 'BiocGenerics'

The following objects are masked from 'package:parallel':

    clusterApply, clusterApplyLB, clusterCall, clusterEvalQ,
    clusterExport, clusterMap, parApply, parCapply, parLapply,
    parLapplyLB, parRapply, parSapply, parSapplyLB

The following objects are masked from 'package:stats':

    IQR, mad, xtabs

The following objects are masked from 'package:base':

    Filter, Find, Map, Position, Reduce, anyDuplicated, append,
    as.data.frame, cbind, colnames, do.call, duplicated, eval, evalq,
    get, grep, grepl, intersect, is.unsorted, lapply, lengths, mapply,
    match, mget, order, paste, pmax, pmax.int, pmin, pmin.int, rank,
    rbind, rownames, sapply, setdiff, sort, table, tapply, union,
    unique, unsplit

Welcome to Bioconductor

    Vignettes contain introductory material; view with
    'browseVignettes()'. To cite Bioconductor, see
    'citation("Biobase")', and for packages 'citation("pkgname")'.

Setting options('download.file.method.GEOquery'='auto')
Setting options('GEOquery.inmemory.gpl'=FALSE)
> png(filename="/home/ddbj/snapshot/RGM3/R_BC/result/lumi/methylationCall.Rd_%03d_medium.png", width=480, height=480)
> ### Name: methylationCall
> ### Title: Estimated methylation call
> ### Aliases: methylationCall
> ### Keywords: methods
> 
> ### ** Examples
> 
> data(example.lumiMethy)
> M <- exprs(example.lumiMethy)
> fittedGamma <- gammaFitEM(M[,1], initialFit=NULL, maxIteration=50, tol=0.0001, plotMode=TRUE, verbose=FALSE)
> methyCall <- methylationCall(fittedGamma)
> table(methyCall)
methyCall
 Margin   Methy Unmethy 
    806    1648    2546 
> 
> 
> 
> 
> 
> dev.off()
null device 
          1 
>