DEGs generate when has a background sample

Question

[dew]

Dear all,

May I know how to generate DEGs when has a background sample (not a group of the control, or treatment)?

The unmatured idea is to use

(treat - background) - (control - background)

to get the DEGs for the comparison of the treatment and the control. So can DESeq2 do this or the only solution lead to limma?

Thanks a lot!

[ATpoint]

Basic algebra tells you that X-Z vs Y-Z is the same as X-Y, so using the same background is redundant and you can directly compare the treat vs control. How kind of setup is this, what is "background" and why is it the same for both?