## ----, echo=FALSE-------------------------------------------------------- knitr::opts_chunk$set(cache=TRUE) ## ----, echo=FALSE-------------------------------------------------------- suppressPackageStartupMessages({ require(minfi) require(minfiData) }) ## ----, eval=FALSE-------------------------------------------------------- # require(minfi) # require(minfiData) # browseVignettes("minfi") ## ------------------------------------------------------------------------ baseDir <- system.file("extdata", package = "minfiData") baseDir dir(baseDir) dir(file.path(baseDir, "5723646052")) ## ------------------------------------------------------------------------ ## 'pData' targets <- read.450k.sheet(baseDir) head(targets) ## 'raw' probe-level data RGset <- read.450k.exp(base = baseDir, targets = targets) ## ------------------------------------------------------------------------ ## Basic QA -- comparable densities across samples? densityPlot(RGset, sampGroups = RGset$Sample_Group, main = "Beta", xlab = "Beta") ## ------------------------------------------------------------------------ ## background correction and normalization ## like Illumina Genome Studio (other approaches available) MSet.norm <- preprocessIllumina(RGset, bg.correct = TRUE, normalize = "controls", reference = 2) ## ------------------------------------------------------------------------ ## How similar are the samples to one another? mdsPlot(MSet.norm, numPositions = 1000, sampGroups = MSet.norm$Sample_Group, sampNames = MSet.norm$Sample_Name) ## ------------------------------------------------------------------------ ## Identify probes with methylation status differing between groups mset <- MSet.norm[1:100000,] ## logit(beta) M <- getM(mset, type = "beta", betaThreshold = 0.001) dmp <- dmpFinder(M, pheno=mset$Sample_Group, type="categorical") head(dmp) ## ------------------------------------------------------------------------ plotCpg(mset, cpg=rownames(dmp)[1], pheno=mset$Sample_Group) ## ------------------------------------------------------------------------ ## Genomic locations mset <- mset[rownames(dmp),] mse <- mapToGenome(mset) # 'SummarizedExperiment' rowData(mse) mcols(rowData(mse)) <- cbind(mcols(rowData(mse)), dmp)