I have proteomic data pertaining to organs of rats treated chronically with a low dose of a chemical. The rats have developed pathologies after the 2-year exposure.

Concerning my proteomic data, I have very meaningful and statistically significant results from the analysis of the KEGG and GO ontology enrichment when I take my data at the cutoff threshold of p<0.01 and fold changes>1.1. it's still there at the fold changes cut-off of 1.5 but much less significant.

I am wondering if one of you know some references explaining whether or not a 10 or 20% decrease or increase level of a protein or a gene can have a biological significance?

Thank you in advance for your help,

The best,