Hi,
In DESeq2, while making MAPlot for an object obtained by using results function, is there a way to highlight only those genes, whose log2FC values are >= |1|. For example:
ddsMat <- DESeq(ddsMat) (res.05_FC0<-results(ddsMat,alpha=0.05,lfcThreshold = 0)) plotMA(res.05_FC0,main="DESeq2_WTGFP_vs_KOHET",ylim=c(-10,10),alpha=0.05)
Now this will show log2FC values which are like 0.80, 0.75, -0.73 also as red. I want to highlight only those values as red which have log2FC values like 1.3,1.2,-1.34 etc i.e >|1|.
Can I do it in the in built function?
Also the default alpha for plotMA is 0.05??
Am i Correct on this ? log2FC of 1.34 from the above output means there is 2^1.34 difference between the groups?
Thanks
Hi Michael
Thanks for the reply. It seems like the default for plotMA is 0.1 from this line
Also I am trying to play with lfcThreshold parameter of the results function(will ask a separate question on it ). In the output file under
log2FoldChange
column, if the value is 2, does that mean the gene difference between 2 groups being compared is 4 times? Thanks for all your help.Yes, a log2 fold change of 2 means the expression goes up by 4 fold. We explain how to interpret the results in this section of the workflow (the workflow is like an expanded version of the vignette, going at a slower pace):
https://bioconductor.org/packages/release/workflows/vignettes/rnaseqGene/inst/doc/rnaseqGene.html#differential-expression-analysis