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Differential gene expression analysis

I am performing differential gene expression using DESeq2 but will be subsetting transcripts based on a pre-determined criterion. Does this sub-setting violate any assumptions make by the statistical package?

rna-seq deseq2

Depends if you filter out 20 or 20000 genes. Please add details.

Of course, I know I can filter, people filter for example low expressing genes, etc. I was hoping for guidance and insights on the statistical assumptions to better understand how I can partition my data.

Please add details.

Why do you want to filter? Default settings are fine in most cases. How many genes, any specific kind of genes, or just lowly expressed?

Unfortunately, I cannot add more details. This information should be enough to answer my original question: Does DESeq2 expect a minimum number of genes?

All statistical testing your doing depends on the size of elements, so, if you reduce the number of elements, your p-value distribution changes.

Sure. This doesn't answer my question.

DESeq2 don't expect a minimal number, but you are modifying your p-values, so you get less DEGs

1 answer

If you use too small a subset, the assumptions underlying the normalization procedure may be violated.

One assumption is, that the majority of genes are not differentially expressed.

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