I am analyzing miRNA microarray data and I would like to establish a fold-change threshold which is biologically significant. Classically for mRNA microarray a 2-fold-change cutoff was used, but I think that if we use that for miRNA as well, were could be loosing some information given that miRNA regulate gene expression. In other words, which is the miRNA expression level change, in which we could see an effect in mRNA expression? 1.5-fold change would be enough? I am asking this because in general, the fold-changes I see in the literature are not very big.

I have seen some papers not using any filtering criteria and others use 2-fold change cutoff. Is there any paper where has been studied this issue? I haven't found anything but there may be some.

Thank you,