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I'm using R and bioconductor in order to conduct some gene analysis on an Affymetrix dataset (GSE173360) but I'm having trouble at filtering genes. I'm trying to create a dataset called small.eset by filtering my dataset but small.eset returns NULL dimensions. I was wondering if I'm doing some obvious mistake?

The dataset I'm using is GSE173360 and I'm sharing my condensed code (without plots and quality checks).

# Library and Data Imports ------------------------------------------------
library(affy)
library(affyPLM)
library(simpleaffy)
library(limma)
library(RColorBrewer)
library(genefilter) 
setwd("/Users/Documents/R Scripts/biostat_geo/data")
Data <- ReadAffy() #read all CEL files in working directory

# log2 transformation -----------------------------------------------------

ex <- exprs(Data)
qx <- as.numeric(quantile(ex, c(0., 0.25, 0.5, 0.75, 0.99, 1.0), na.rm=T))
LogC <- (qx[5] > 100) ||
  (qx[6]-qx[1] > 50 && qx[2] > 0)
if (LogC) { ex[which(ex <= 0)] <- NaN
exprs(Data) <- log2(ex) }

#background correction

eset <- expresso(Data, bgcorrect.method = "mas",
             normalize.method = "loess", 
             pmcorrect.method = "pmonly",
             summary.method = "mas")

# filtering

esetunlog <- 2^exprs(eset)
ffun <- filterfun(pOverA(0.20,10))
t.fil <- genefilter(esetunlog,ffun)
small.eset <- (log2(esetunlog[t.fil,]))
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