I am wondering how big should be the library for each sample to big enough to detect meaningful differential expression please? Is 15M reads or 25M too small?
I found this paper from 2011 that discuss this matter and it seems that when one is mainly interested in protein coding genes, the depth do not have to be very big: http://genome.cshlp.org/content/21/12/2213.full. But it was written 4 years ago. Is it still true please?
What is your experience please ?