overlap of 25 genes in 05_overview_enrichment_analysis.rmd

[yeroslaviz]

Hi, thanks for a great book

I don't get the number given as an overlap here. In the explanation of the over representation analysis you give an example with 57 DE genes and 28 of them are in the gene set of interest.

Below the the code example in this section comes the sentence

Whether the overlap(s) of 25 genes are significantly over represented in the gene set can be assessed using a hypergeometric distribution. This corresponds to a one-sided version of Fisher’s exact test.

Where does the number 25 comes from? Shouldn't it be 28?

thanks